To learn more about electronic's in a different and very effective way, and get access to my circuit designs, click here: www.patreon.com/MrCarlsonsLab
Hi Paul. This is an excellent approach to involve the viewers in the visual approach to fault finding. I have been watching your channel for a couple of years now and have learnt so much because of your detailed presentation. I have fixed my own tube amps without any specialist equipment and built a couple of projects because your videos have taught me about component identification, their purpose and weaknesses. I get lost in electronic theory but when it comes to repairs you have taught me that symptoms often lead directly to the problem. I think I may well take a look at your Patreon course. Keep up the good work and in the words of your fellow countryman and UA-cam guru, AvE, keep your stick in a vice, Thanks. Edit, By the way, I think there might be a high enough demand for some of your DIY projects to be marketed in kit form or at least the PCB's. Specifically I am thinking of the Carlson Super Probe which strikes me as an excellent piece of equipment, and the capacitor orientation tester. I am sure there are more. Hope I have not committed a faux pas by replying to a pinned comment. Deletion is you prerogative. Cheers.
I've learnt so much from this 1 video. Your detailed explanations for people that don't have the same experience as you, is more valuable than money! Mr Carlson, on behalf of everyone trying to learn "properly" about electronics... THANK YOU for giving so much valuable knowledge and time, for almost nothing in return! The biggest thank you, is from me! Cheers from Hobart, Tasmania, Australia!
Hello Paul - Than you for such a great informative & instructional video. I learn so much from you even at 74 years young. All the best from County Clare Ireland ☘
Hi Mr Carlson I love watching your videos' I am not an electronics person my life was spent as a mechanic on automotive transmissions for over 40 years retired now ,Yet I find myself watching everything you do, I think your incredible Thank you for your expertise you are my late night watch Thanks Joe.
I have worked with two guys in my electronics life, one of which trained me. I thought he was the greatest, and in his own right he is. You my friend are a genius, as I've picked up many little tidbits that have eluded me to the point of loosing sleep at times. Thanks for your work and answers to stale questions.
I paused the video when you asked people to spot the design flaws on the top side, I looked it over and I came to all the same conclusions that you did about the audio output transformer and tubes being way too close to the power transformer, and they were also not rotated. And the only reason I knew this was because I've been watching your videos for a couple years now and I've learned so much. Thanks for being an awesome teacher Paul. Edit - Also I guessed correctly about the ceramic capacitors on the bottom side being wrong for that type of circuit! I missed the other two things you pointed out, but I think I did ok considering two years ago I was clueless about this stuff.
I guess the reason why they put transformers the way they did was to keep the weight balance for the device as a whole. It should be comfortable to carry around, which means transformers should be in the center. They would probably love to put them at 90 degrees angle, but that was most probably not feasible given the sizes they had to adhere. Commercial engineering is always about compromises.
Excellent video ! For a old retired engineer like me it makes me proud that young engineers like you take our profession so seriously ,always looking at every possible circumstances in the present and future of a circuit we are servicing or design. Keep up your more than excellent work ! :)
@@mrpedrodrodriguezsr7628 There's still no problem with mid-age engineers at ~50, however things are much worse with next even younger generation at ages 20-30, which mostly have lost understanding of strict and harmonic real world laws because of too much sinking into various inferior human-made virtualities.
One quick tip about permanent marking issues: quite often, if you take a dry board marker pen that is erasable, and scribble over the permanent marker you want to remove, the chemical make-up of the erasable ink will soften the permanent ink to the point it can be wiped off the surface of where it was applied. I have done this on a number of items including equipment chassis. Sometimes you have to scribble over, wipe, and do it over again until you've removed all traces of the permanent marker ink. Scribble over the permanent marker with the dry board marker until it causes the permanent marker ink to smear then wipe before it has a chance to dry again, repeat as needed.
Boy I even can't imagine how many effort it takes, to make a 2h video containing such great and educational content nor how you are able to put so many useful information in it during one repair! I really like that you added many parts, in which we could pause the video and make our own guesses! Thank you for spending the time and effort providing in my opinion, the best electronics channel on YT! Thank you very much Paul!
Hi Mr Carson, every time I view your channel I'm amazed on how you acquired all that equipment. I'm a Amatur radio operator and I know what my equipment in my Ham shack cost me, so how in the world did you acquire all that great stuff. Boy, I sure would like to read your biography, it must be interesting reading. By the way, keep the UFO project as it was intended to be. Thank you for what you do.
I totally hadn't thought about power transformers inducing hum in audio transformers until now. In my own tube amplifier that I designed/built, I always had a little bit of hum at the output, and I always assumed it was due to poor B+ filtering. It's only now that it occurred to me that my audio transformers are sitting right next to my filament transformers, in the same orientation. I definitely learned something today!
Nice job, sir. I bought a non-working Cponar 230 tracer off eBay several years ago. It was non-working, but cosmetically gorgeous. These were sold as kits, and the original owner had made a wiring mistake, so the unit was essentially new. I went through the wiring and found the error -- and it works perfectly. It's an interesting design, quite different from your Stark. It uses a 6AB4 in the physical probe, and uses a 6X4 rectifier. It looks like a TRF receiver, tube lineup 6GM6 x 2, 6AV6, and 6AQ5. A 6E5 is the eye tube and a 6X4 the rectifier. I turned it on this morning, bearing in mind your comments, and noticed a very healthy feedback squeal if I turned up the gain. Took it out of its cabinet and noticed the many ceramic disc caps in the circuit, QED. I took some photos, but don't see how to attach them here. The schematic and manual info is free online. Thanks for your very careful videos, I've been around this stuff since I was a kid in the 50's and can well appreciate your presentations.
What a contribution - for children to all the rest of us - the quality of these productions, your methodology and flow are well presented and useful. Dear Mr. Carlson, just last evening for some reason I was thinking of my shop teacher while attending junior high. I know he has moved on, however the thought of the positive impact he has had on me, many years later caught me by surprise. Why did I think of him? I just continued to realize his contribution. He thought he was teaching shop however he was teaching much more. Without a doubt, you are having that same impact. Your teaching techniques, production and applied electronics are all superb and admirable, however, you are also presenting a way to think and behave. I have nothing but praise in that you are elevating the world around you, something I wish to do.
I like the backstory with the "nicotine brown" paint colour. Reminds me of "fake plants", "artificial wood grains", "air fresheners", "fake christmas tree snow made of asbestos", "highly flammable patent leather", and vintage tiny hotel rooms with completely mirrored walls directly opposite of the entryway. Hammertone black, or even a dark hammertone grey would suit the case well.
I noticed it multiple times so I looked up its manual and found out it is another name for overload or open line or even short same as if your multi-meter would show when it showed open line or short as OL in things like capacitance
This unit was in such good condition because the hum drove the techs crazy and they shelved it. Novice engineer designed it to look nice to the eye not really to work nice. Paul never ceases to amaze me with the info he has. Thank goodness he is sharing it with us. But I do have one question after all these years of watching. How does Paul manage to have such well manicured fingers?
It is a privilege to see how Mr Carson sets about identifying faults and repairing these pieces of equipment. The breadth of theoretical knowledge and practical skill are wonderful to see and a great example for anyone contemplating a technical project of their own.
One of the fastest to pass 2 hour videos I've seen, great work, going to be binge watching from now onwards. Thanks for sharing, you're a natural teacher.
Hi Paul I have a scanner that is stuck in A.M. it won't switch to F. M. and the squelch is not effect ive if I turn the squelch which trim pot is the squelch?
Thanks again Paul for another great video. You took the tracer from discovering the problem to re-engineering the solution. Now I am looking forward to your next Vedolyzer episode. 73, Ski
WOW!!! "The HEART of the ART"!! FANTASTIC VIDEOS!!! Mr. Carlson, I find your video so well descriptive that when I am watching one, it keeps me on the edge of my seat "more" than if I was in a movie theater watching a world renowned thriller "or" who-dun`it!!! Your analytical skills combined with A++ Communication are truly "The HEART of the ART"!! FANTASTIC VIDEOS!!!
Screen grid tubes are relatively insensitive to plate voltage variation. That's why you can get away with ripple in the plate supply. They're basically a voltage controlled current source. Nice vid!
I love that color on the case! Reminds me of the gear we used in Vietnam back in 1971 in the Landline Teletype hut, we had amplifiers for the machines that would pickup our machines, boost the signals and send it many miles to our daughter units. The signals needed to be strong since they were all encrypted using crypto gear.
Mister Carlson good morning and Thanks for the share I'm learning many things about the tube and the " tricks " in repair and restoration !!! Your knowlege is very precious for me !!! please continu your works and the videos ... Your lab is fantastic ( a dream for me ) Sorry for my Englih but i'm a low level tech and in France at my age ( 60 ) never we learn you langage ...( except by myself ...) Very Good day Mister for you and your familly (Eric from France in Normandy )
It always like I've been at college level course when I spend time at Mr. Carlson's Lab! Thank You Mr. Carlson for all the time you send here with us, I'm sure I speak for us all in thanking you for all you've done for us here! When I get ready to tackle my '36 5 Band Philco Floor Model 116x this spring I'll be thinking of you the whole time. My Variac has arrived along with the sockets for the light bulbs (along with the 2 60 watt Edison style bulbs just to get that "old time radio' feel!). All that's left now is the isolation transformer design. There I'm having to improvise. So, what I've done there is get as many COPPER winding ONLY transformers I could get (I've got 8 so far) from old microwave ovens. 6 are from 1200 watt + ovens and 2 are from 800 watt ovens. From all I've read I have found that If I go from the 120 volt to 2000 volt windings and back down to 120 volt again I can still get the desired isolation. I know I'll lose a bit of amperage each time so that's where the extra transformers come in. If I use pairs of equal power inputs and outputs each time and keep the neutrals correct each time I'll then end up with several matched transformers all outputting 120 volts, all in parallel with about 4 to 6 amps each time, but with the ending total amperage around 12 to 15 amps. Once that is done I'll be ready to take on my radio. As the saying goes: Wish me luck! If somebody sees any flaw in my design with these transformer concepts I'll gladly accept any suggestions. Cheers!
Since I watched the entire video, I think I understand why you didn't add a fuse to this piece of gear, but I think I would have preferred to have done so. You know, if you produced 100 videos per day, I would still be wanting to see more....you do such an excellent job. I think one of the things about your videos I appreciate the most is that you speak so that beginners can easily understand important principles, yet it isn't "dumbed down" too much for advanced and more experience Electronics Techs. Thanks for your excellent work.
What a very nice documented repair Paul. Your style and presentation was just perfect on restoring this old bit of history. One day I can only hope to be as good. Thanks as always for sharing your knowledge.
phenominal paint job really kudos it looks great. I really like the eye watt shadow thingy, especially the turquois color. Wished more companies would go retro and go back to these exterior design styles.
Wow! Mr Carlson has produced a truly awesome video here. I love all the tips and side notes along the way. Absolutely no problems with the length as it's easy to stop and continue where you left off. I have to say that my favorite topics will always be old time (vacuum tube related) test equipment repair and renovation. Thank you for your outstanding high quality educational content Paul. - Dave
whenever i get old kit with the cord chopped off its because some sensible tech has cut it off as it needs recapping or other repairs, it just stops muggles plugging it in and killing it. another reason is live auctions, here in the uk if an auction house sells a lamp or scope or other electronic kit it should be "PAT" tested if it has a power cable, so they chop them off it saves them money and ensures a qualified person will at least have to open it up to re-cable it, well thats the theory anyway.
@@Willam_J I hear you, possibly the more we politely inform people about electrolytics, powering up old gear without a speaker load, and the fact that a lot of it was built in a time when wall power was lower... It just seems that the human thing to do is plug 'er in, hit that power button, and see if she lights up.......or fries!
Just wanted to say I love watching your videos as I do a lot of engine building it's great watching something informative and not what I usually work on 👍
VERY interesting Paul, especially the twisted filaments story. Many years ago I was an electronics tech for the RAF, mainly on radar. On leaving I went in a completely different direction but watching your channel has rekindled my enthusiasm. You are obviously very knowledgeable and passing this information on in an organised manner is another great skill you possess. Thank you for your time and knowledge.
My guess is that this design was from end '60. I have repaired all sort of audio and clockradio's in the thousands in the '70 (for a company), all manufactured in Asia; Japan, Malaysia, Taiwan, Singapore and more (Nothing from China yet, although China thinks different now about Taiwan). Every device, not one excluded, was fitted with a shielded power transformer like the one we see in this design, even the brown lacquer is the same. I speak about more than a hundred different designs. I think at the time it was presented by the transformer manufacturer as a 100% solution, but was not. I have rarely seen such transformer die, but the problem they can have is that the laminated core starts to hum mechanically. The simple solution is to put a plumbers pipe wrench in every of the 4 corners when warm, and squeeze as hard as you can. This technique has never let me down. I am going watch the rest of the video, I am only at minute 13...
Erik den Houter It’s sometime possible to produce a canceling magnetic field individually for whatever component is suffering. You basically make a space coil of a few windings, and power it through a VR from the filament winding. Then manipulate the coil and the current setting until the hum from that one part of the circuit is gone. The. Replace the VR with a fixed resistor. This method can be applied several times, although the fields will interact somewhat, so it’s somewhat time consuming but can be made to work. It works quite well in tight designs where it’s impossible to sufficiently separate the circuits from the transformer. A LF magnetic sniffer probe will allow determining field orientation, strength and uniformity before committing to any particular mitigation. Then of course the problem with coupling between nearby transformers is that it can well be nonlinear, so you may end up having to add some saturable material in critical places to produce the right harmonic mix that cancels out the nonlinearities. It’s not a generally applicable nor even practical solution, but I’ve seen very tight transistor-era circuits that had several space coils that mulled out the field produced by the transformer. Such circuits are hard to troubleshoot, since addition of any major conductive loops alters the field and reintroduces the hum. The one I have seen was a circuit for aircraft use and ran off 400Hz AC. A few slivers of permalloy, seemingly randomly placed, acted as saturable cores. Someone must have spent a lot of time tweaking it to cancel out nearly all the hum.
Awesome videos you create. ❤️ I don't think anyone could possibly explain your troubleshooting and re-engineering techniques better than how you explain all of this. How you say you can go on about everything that is really going on is so true. I remember as a TV technician, one of the instructors pointed out an interesting item when we were introduced to PWM power supply technology. In the front of the power supply, you first have your full wave bridge rectifier with your typical 4 diodes. Paralleled across each diode is a small ceramic disk capacitor. We all have seen them and never thought much of why they were there. As you mentioned, ceramic disc capacitors very rarely fail. I've never seen one of them fail in this application either. Well, this instructor told us the purpose of them. They filter out "silicon radiation." Basically, it was explained that just like any switch contact or relay contact, you'll have an arc spike generated. This ends up as an interference getting through and can appear as thin lines in the video. So, as these rectifier diodes are doing their switching 60 times per second, you'll generate "silicon radiation." As far as "AC hum," we were taught that 1/2 a volt AC ripple or less was acceptable in TV power supplies. It's these little engineering items that make electronics such a complex technology. I don't believe that there is one person in the whole world 🌍 who knows everything about electronics technology. Especially when you consider all the various areas of electronics such as communications, RF transceivers, radar theory, optoelectronic technology, electro mechanical technology, automotive electronics, and so on. Some of the way they have made mechanical sensors. One that comes to mind is these small weight measuring digital scales. They are interesting when you look inside of one. I think they use a physical precision machined resonant tuned tank circuit, and the slightest distortion or bending of the machined aluminum block causes a change in its resonance??? It's amazing that it is so basic looking and relatively durable design. Maybe you can give insight sometime of how those sense weight also how they use other sensors like optical shaft encoders for rotation position in electronics.On the principle of how those scales work, that was my own theory and is subject to being wrong! LOL 😆 I'm sure you know this and may even own such equipment. Some audiophile people who are into high-tech home stereo systems actually use mono-block tube amplifiers in their systems. They provide a lot of current amplification to drive bass 🔊 speakers well. I was told that tube amplifiers have a type of distortion, maybe harmonic? It's inherent in tube amplifiers, and it happens to be pleasant to the human ear 👂 This is why tube amps sound good. I saw a system at a customer's house that I was working on their big screen TV. Off to the side corner of the living room was this fancy waist high table. It had a glass or acrylic see thru box on top, housing this mechanical mechanism all shiny brass (looked like gold) and polished aluminum pieces inter-mixed in the assembly. It was a $20,000+ turntable! (Record player, lol 😆) All high precision metal parts and a really intricately desigcounterweightight system for the needle land weight. It had miniature steel cables for some of the design, probably stainless or nickel metal. This thing looked like it belonged in the Smithsonian Institution!!! The woman customer said,"Yeah yeah, that's some of my husband's crap!" 🤣😅🤣 Then asked if I needed her to move one of the mono-amps away from the TV while I worked on it. I said, "Yes, please, that'd be great!" Because I sure as hell didn't want to be responsible if anything happened to it. Stuff like that, you don't even want to touch it, just in case something happened to go awry, even though it had nothing to do with you. Experience! That is also how we learn electronics is mostly experienced from others, such as here in this great video! 👍 👌👍
I'm enjoying The new series, so cool I really dig the resterason videos. I have robotnight almost every Saturday night,and I'm always watching your restoration videos. thank you Paul, for mr Carlson's lab
In a previous life, well previous job so to speak, I did gunsmithing. We used a bead blaster to prepare firearms for hunters who wished to have a mat blue finish. To keep the finish from being damaged after bluing, before putting them in the tanks, we did the bead blasting, then followed with a medium steel wool dipped in kerosene. This had a tendency to knock off any peaks that were let over from the bead blasting and insured that a rifle barrel getting bumped by the dash of the pickup did not show the bump in the mat blue finish. Leaving out that step did result in some bring-backs of rifles after the first or second hunting trip because such "bruises" showed up in the nice mat finish.
Beginning engineers do the same thing in vehicles, I can't describe all the silly and avoidable problems some kid with a computer and a degree can create. However, if everything was perfect right from the factory, I would never have had a career fixing problems. You show me all the things I need to know about circuit design, stuff nobody else talks about. Vehicles have so many electronic controls, you must have some experience with electronics to troubleshoot systems. Many older mechanics retired when carbs were integrated with computers, I had to learn the systems, there was no way around it. Most mechanics today are not mechanics, they just replace parts til the problem is found, and this is at the customers expense. I don't know how they get away with it, no wonder the oxymoron "Honest mechanic" exists. I am an Honest Mechanic, not many of us left.
Isopropyl alcohol does a good job removing permanent marker if it hasn't been on the paint for years. For marker that has been on paint for years or decades there is a product called write away graffiti remover that works very good. I used them all the time to remove permanent marker from medical equipment (hospitals love to write on rental units.)
Perhaps the marker ink you are removing is not as permanent. I have tried to remove 10 year old Sharpie brand black ink with isopropyl alcohol. It takes off about 80 to 90 percent of the ink. That final 10 percent is soaked into the paint. Acetone will get it off along with the paint. However the red and blue Sharpies are the easiest to remove with alcohol alone.
Very well explained and demonstrated, making tracing problems with old American Radios using such design compromises "back in the days." Showing how expensive added component costs would have made the radios and Test gear prohibitavly more expensive and retail prices would have required to follow. Replacement with modern affordable components and circuit changes made a huge change. Of course Mr Carlson has a professional mindset, knowledge and ability to produce enlightenly usefull videos that many of us find very useful, Thank you.
I have been studying electronics my whole life and have been getting more addicted to your channel every day, I just want to pass along my apreciaction to you fo sharing your knowlege with us. I am so happy that there are people like you out there that have such a vast amount of knowlege in what they do,its mindblowing. I've noticed that whenever humans accomplice great things they like to give aliens or diving intervention the credit for it,when in fact its people like you that build the pyrimids or get us to the moom,anyway I hope you understand what I'm trying to say,thank you sir Im a tru fan even though I understand most of what your saying its fun to try haha.
I can't say that I understand much about the electronics side, but it fascinates me nonetheless. I can say with certainty that the refurb looks absolutely stunning.
Mr : total respect and respect total well done !!! a great lesson and thanks for that .... you are the best on YT !!! at 61 years old i'm learning with you ... sorry for my american langage but i'm living in french country .... God bless you and your family Mister and Merci for the share ... Eric from France ...
You've taught me so much ! To show my appreciation, I will be signing up on Patreon ! Not sure what level yet, but what you've shown me in this video alone was worth way more than $20 ! Thank you !
Sir, with your knowledge of all those audio engineering quarks, like ceramic disc capacitors being micro-phonic and some of the other items you mentioned, you would probably make for an excellent audio engineer at companies like, Nakamichi, Proton, and Bang & Olufson ! Great knowledge and great videos! 👍
I was checking emails and wrapping up personal things after getting home from work, eagerly getting ready to head to my "lab". Suddenly, up pops a Mr. Carlson video notification. Hmm, Almost 2 hours? On a signal tracer? That has to be good! Well, I guess that Atwater Kent 20c can wait a while longer. (Darn you, Paul Carlson! Get off my lawn!) Thanks Paul, for another really good video. I'm an old timer who cringed a bit when you strapped that big capacitor to the diode. I had a feeling what the result would be, though. I never fail to learn from your videos and appreciate the effort that you put into narrating, recording and editing your work. Producing quality videos is quite a task in itself, regardless of content.
@@MrCarlsonsLab The audio and the video quality is superb. I was wondering how you could shoot those videos in so dim a light and get no noise. Now I know. But I'm still curious about the editing software.
That is such excellent tutoring, thumbs up Mr Carlson, you pay great attention to details and pass on to others, valuable info for the younger generation as the old techs sadly pass together with their wealth of knowledge :-( If I may add a small tip on how to greatly reduce the magnetic stray (and resulting hum) to the output transformer and output tube would be to cut a shield out of 1,5-2mm steel plate, wider and higher than the power transformer and an angled off long flap at 45degrees on the right to also shield off the output tube. This plate can then be fastened to the power transformer with double sided tape to ensure that there is an air gap. I know it is a bubble gum bodge rework for a design flaw, but would save relocating components on the chassis. And it works pretty well, back in the heyday we repeatedly had those little Philips Philettas come in wth a totally screwed up and crooked magic eye, it was because of the close proximity of it to the mains transformer and loudspeaker magnet would magnetize the green screen to a point of no readout. The installation of a shield and de-magnetizing of the tube solved the problem on all of them forever. Best regards from Germany
Unfamiliar with curve tracers after switching my electronics hobby to computers; but, 50 years ago I made something from junk box parts from a vintage electronic hobbyist magazine article. The "Octopus" circuit was reportedly common to find in consumer electronic cabinets for onboard testing. I had my contraption near an oscilloscope when a friend brought his solid state reel-to-reel stereo tape deck for repair. One channel worked; the other was dead. I wondered how fast it might be to find any fault with that thing. Comparing the trace of components in one channel against the faulted side a transistor on one channel did the same trace as your diode here. Ha! Took about six minutes. I replaced the good transistor and the bad one with a matched pair. The deck was still doing well when I left town for a new job. The thing I liked about your design was that you turned an octopus into a curve tracer by adding a meter circuit and a meter. My octopus never even made it into a case and except to satisfy my own curiosity I never needed it again. I'm not going to build one. However, I am going to look up your curve tracer circuit right now just to restore a great little memory.
Ah, I am a bit long in a tooth, and I remember these... the screws were as loose as my tongue, and they originally came with a carton of Camels... those were dangerous times... one morning after too much extra caricature activity, I woke up with one digit missing. The ex swore up n down that a strange creature broke into the house and removed said digit, but didn't touch anything else... But now that I reflect upon the matter, it could have been a lot worse, if you know what I mean. I must now go join your patriot page. I have many questions for you. Always a pleasure, and looking forward to your next vid. Thanks! Learning so much and please don't take this personally, but your videos put me to sleep fast when I need it. Thanks again!
@@MrCarlsonsLab Now that's funny! I usually don't sleep because I'm watching one of your videos for the nth time and taking notes. But eventually I get that weird sleep deprivation lsd stuff and I must recharge the old battery. But like I said earlier, I need to go join your patio page, so get a hold of yourself and just be grateful that you still have all your digitals. Ha! Catch you later alligator clip. 🤣
@Full Wave Recked Took me a while to work out that you meant "extra curricular" activity (Unless of course you draw cartoons). Looking on the positive side, even with one digit missing you can count up to 256 in binary or 262144 if you also use your toes.:-)
@@TheSharkey22 yes. A ply on words. Word. I'm trying to find like minded folks local, but haven't had any luck. Will not give up. Thank you for taking the time to respond. I appreciate it. Keep in touch.
wow, that star ground trick hits me in the same way as when the engineer i was working for in high school told me that when recording, you move the microphone to the point where the sound source sounds best. "the important thing is the obvious thing that nobody is saying." -bukowski
Stark made really good equipment. I just repaired a Stark 10-A signal generator which when I put it on the frequency counter was amazingly stable for a Colpitts oscillator. They made a lot of electronics for to Nato specs for the Canadian military. I also have an excellent Stark tube tester which I believe was made under license to a Hickock design. Hickock tube testers were top of the line.
One thing I missed in this video was that you showed what change it would make to the hum in the speaker by rotating the output transformer 90 degrees to the power transformer. But the case and speaker grill really turned out nice.
I spent my career digging holes as a construction laborer and retired early pretty much wore out. Finding your channel and others like you passing on your knowledge is inspiring. I feel like I'm in my own private shop class just soaking up the information like a sponge. Wow! Thank you.
Good point about discharging capacitors. I opened up a faulty 5V switch mode power supply that had been disconnected from AC mains for three days. When I picked up the circuit card I got quite a nasty shock. The 82 microfarad input smoothing capacitor was still holding over 300 Volts! (I'm in the UK - around 240 Volts here)
Not that safety was a high priority in those days, but maybe the hum from the transformer location was deliberately allowed to remind technicians that the tracer was still turned on?
I always like your videos, there are not many youtubers that can make a 2 hour video I watch to the end. Being made for audio trouble shooting I assumed the Watt meter was an input for an audioamp (dummyload/powermeter) Funny because I have an old AVO CT38 VTVM that has a powermeter too. Being a VTVM I assumed that it was something to measure the power consumed by a DUT (like your signal tracer) but this it turned out to actually be a dummyload/powermeter. That proves it, assumption is the mother of etc..... :-) - My first working electronics project was an RF/AF signal tracer on a self etched PCB from an Elector schematic. I still have it. I used it a lot way-back then (1980's). Nowadays I repair industrial electronics, testgear and calibration gear for a living and that is not something you need a signal tracer for. About 10 years ago I made one from an old ham1940's HAM magazine. It had auto switching between RF and AF and a magic eye as optical (signal strength) detector. Did not use it, was just for the fun of building. If you are interested, on the bottom is a link 3maart1946, if you click that you get the pdf copy from the magazine article. It is in Dutch but the schematic will probably be enough for you. www.pa4tim.nl/?p=1332
Dang. Paul, I've been scratching my head for months wondering what the heck the "current transformer" is for in my Eico 147A. Staring at the schematic for hours didn't help, but after this video, I can stop scratching my head, and for that I profusely thank you... the bald spot should grow back soon... thanks!
The ripple voltage on the filter cap is proportional to the charge consumed by the circuit during the cycle divided by the capacitance, so multiplying the capacitance by 3/2 like you did will multiply the ripple voltage by 2/3 (which it did). Using a full bridge rectifier will cut the cycle time in half, thus reducing the charge consumed per cycle in half and so the ripple voltage would be cut in half as well.
Another great video, Paul! I really appreciate your schematic walk-throughs as that, for me, was the hardest thing to learn about electronics. 40 years after taking my college electronics courses it's all finally coming together thanks to you an your videos!
Paul, very informative video on a simple ( I thought ) piece of test equipment. The explanation of the different components in an audio circuit was very good. I learned a lot of things I didn't know. Thank you for being so thorough for us laymen to understand. Dave
Hello Mr. Carlson, I am a wanna be electronics enthusiast. I am also, totally blind. I do have light perception, and I love all things, antique, mechanical and electronic. I own to wind up, phonographs, and hope to get my hands on an antique radio at some point. I know that there are blind ham, radio operators, but is it even possible, or wise, for a blind lady to get her hands dirty on the workbench messing about with all the electronics. Is it even possible for us to fix things like this? It did, however, make my heart sing to hear the words audio oscilloscope. I.e., the signal tracer. We are currently restoring in this video. Thank you for bringing us along with you. My vote for the new color, would’ve been a nice, dark, hunter green, but I see why you went with black, for the white face of the machine.
I do not think you know the real Carlson effect. The simplified version is the one you are referring to. The real version is: 1. Carlson corners the market in his hidden underground layer 2. Carlson renovates one item in storage 3. Everyone goes crazy on auction site 4. Carlson's listings on auction site sky rocket 5. Carlson apparatuses across the globe reinvigorates the tech industry, one boy at a time
Funny you mentioned the Carlson effect... i commented to Shango066 once about his effect on prices too. Specifically the GE world radios. After his video, the prices shot up for a while on Ebay. Shango responded "i just wanted to point out a good radio" meaning sensitive. Just shows how large they two guys audiences are. Pretty neat.
@@franklynpolster8949 I would love to see these guys sit down around an old TV and work together on one just to see what would ensue. mr. Carlson would probably wind up macgyvering together a device which manually changes his mind.
Thank you for another very interesting video. I am looking forward to you working your magic on this piece of equipment. I am very much more at home with valve technology than solid state. besides my hands are not steady enough to solder solid state stuff now. I was always told that if the power cord is cut off, then definitely do not attempt to fire it up until all the electrics have been checked, as it most likely has an electrical fault,- shorted power transformer/main filter capacitors,ect.
A good demonstration of the fact that in guitar and microphone preamps, input stage resistor quality is more important than transistor quality as far as hiss is concerned. Transistors and ICs are often berated as being hissy in such circuits compared to tubes, but the real reason is that the tube typically has no current carrying resistors to the grid, which is at 0v. The transistor being an 'enhancement mode' device requires base bias of some kind to work, and that is where the hiss comes from if poor quality resistors are used. .
Beautiful Hammertone and amazing piece of test equipment. I have to admit I would have been dubious from the start if it was anyone else attempting this.
To learn more about electronic's in a different and very effective way, and get access to my circuit designs, click here: www.patreon.com/MrCarlsonsLab
Hi Paul. This is an excellent approach to involve the viewers in the visual approach to fault finding. I have been watching your channel for a couple of years now and have learnt so much because of your detailed presentation. I have fixed my own tube amps without any specialist equipment and built a couple of projects because your videos have taught me about component identification, their purpose and weaknesses. I get lost in electronic theory but when it comes to repairs you have taught me that symptoms often lead directly to the problem. I think I may well take a look at your Patreon course. Keep up the good work and in the words of your fellow countryman and UA-cam guru, AvE, keep your stick in a vice, Thanks.
Edit, By the way, I think there might be a high enough demand for some of your DIY projects to be marketed in kit form or at least the PCB's. Specifically I am thinking of the Carlson Super Probe which strikes me as an excellent piece of equipment, and the capacitor orientation tester. I am sure there are more. Hope I have not committed a faux pas by replying to a pinned comment. Deletion is you prerogative. Cheers.
Thank You for your feedback and kind comment as well! I'm very glad this channel is of benefit to you.
Your sybilants are hissing slightly and your breath in mesquite loud. Have you changed your mic?
Why Mr.Carlson ? why!! ?? I love beige!!! lol
Had a eico I wired used to fix stereo equipment yrs ago with it just a audio amp . very handy device .don't touch the case in the bathtub.😁
I've learnt so much from this 1 video. Your detailed explanations for people that don't have the same experience as you, is more valuable than money!
Mr Carlson, on behalf of everyone trying to learn "properly" about electronics... THANK YOU for giving so much valuable knowledge and time, for almost nothing in return!
The biggest thank you, is from me! Cheers from Hobart, Tasmania, Australia!
Thank You for your kind comment, and feedback too!
Hello Paul - Than you for such a great informative & instructional video. I learn so much from you even at 74 years young. All the best from County Clare Ireland ☘
Hi Mr Carlson I love watching your videos' I am not an electronics person my life was spent as a mechanic on automotive transmissions for over 40 years retired now ,Yet I find myself watching everything you do, I think your incredible Thank you for your expertise you are my late night watch Thanks Joe.
I have worked with two guys in my electronics life, one of which trained me. I thought he was the greatest, and in his own right he is. You my friend are a genius, as I've picked up many little tidbits that have eluded me to the point of loosing sleep at times. Thanks for your work and answers to stale questions.
He is definitely a genius I think.
I paused the video when you asked people to spot the design flaws on the top side, I looked it over and I came to all the same conclusions that you did about the audio output transformer and tubes being way too close to the power transformer, and they were also not rotated. And the only reason I knew this was because I've been watching your videos for a couple years now and I've learned so much. Thanks for being an awesome teacher Paul.
Edit - Also I guessed correctly about the ceramic capacitors on the bottom side being wrong for that type of circuit! I missed the other two things you pointed out, but I think I did ok considering two years ago I was clueless about this stuff.
cord was cut to use it for another project?
I guess the reason why they put transformers the way they did was to keep the weight balance for the device as a whole. It should be comfortable to carry around, which means transformers should be in the center. They would probably love to put them at 90 degrees angle, but that was most probably not feasible given the sizes they had to adhere. Commercial engineering is always about compromises.
I enjoy your no nonsense intellectual manner of speaking. You have the sound of an excellent teacher. Always an enjoyment to learn from you.
Excellent video ! For a old retired engineer like me it makes me proud that young engineers like you take our profession so seriously ,always looking at every possible circumstances in the present and future of a circuit we are servicing or design. Keep up your more than excellent work ! :)
He is 51
@@Tangobaldy Which means that I was already a engineer when he was born , so young in my point of view ! :)
@@mrpedrodrodriguezsr7628 There's still no problem with mid-age engineers at ~50, however things are much worse with next even younger generation at ages 20-30, which mostly have lost understanding of strict and harmonic real world laws because of too much sinking into various inferior human-made virtualities.
I am eternally grateful for the priceless service you are preforming in these videos. Humanity hasn’t given up yet.
One quick tip about permanent marking issues: quite often, if you take a dry board marker pen that is erasable, and scribble over the permanent marker you want to remove, the chemical make-up of the erasable ink will soften the permanent ink to the point it can be wiped off the surface of where it was applied. I have done this on a number of items including equipment chassis. Sometimes you have to scribble over, wipe, and do it over again until you've removed all traces of the permanent marker ink. Scribble over the permanent marker with the dry board marker until it causes the permanent marker ink to smear then wipe before it has a chance to dry again, repeat as needed.
Boy I even can't imagine how many effort it takes, to make a 2h video containing such great and educational content nor how you are able to put so many useful information in it during one repair! I really like that you added many parts, in which we could pause the video and make our own guesses! Thank you for spending the time and effort providing in my opinion, the best electronics channel on YT! Thank you very much Paul!
Thanks for your kind comment Ralf. You know, when all is quiet, I have disappeared to the lab. On to the next project......
Mr Carlson's Lab l
Hi Mr Carson, every time I view your channel I'm amazed on how you acquired all that equipment. I'm a Amatur radio operator and I know what my equipment in my Ham shack cost me, so how in the world did you acquire all that great stuff. Boy, I sure would like to read your biography, it must be interesting reading. By the way, keep the UFO project as it was intended to be. Thank you for what you do.
I totally hadn't thought about power transformers inducing hum in audio transformers until now. In my own tube amplifier that I designed/built, I always had a little bit of hum at the output, and I always assumed it was due to poor B+ filtering. It's only now that it occurred to me that my audio transformers are sitting right next to my filament transformers, in the same orientation. I definitely learned something today!
Nice job, sir. I bought a non-working Cponar 230 tracer off eBay several years ago. It was non-working, but cosmetically gorgeous. These were sold as kits, and the original owner had made a wiring mistake, so the unit was essentially new. I went through the wiring and found the error -- and it works perfectly. It's an interesting design, quite different from your Stark. It uses a 6AB4 in the physical probe, and uses a 6X4 rectifier. It looks like a TRF receiver, tube lineup 6GM6 x 2, 6AV6, and 6AQ5. A 6E5 is the eye tube and a 6X4 the rectifier. I turned it on this morning, bearing in mind your comments, and noticed a very healthy feedback squeal if I turned up the gain. Took it out of its cabinet and noticed the many ceramic disc caps in the circuit, QED. I took some photos, but don't see how to attach them here. The schematic and manual info is free online. Thanks for your very careful videos, I've been around this stuff since I was a kid in the 50's and can well appreciate your presentations.
What a contribution - for children to all the rest of us - the quality of these productions, your methodology and flow are well presented and useful.
Dear Mr. Carlson, just last evening for some reason I was thinking of my shop teacher while attending junior high. I know he has moved on, however the thought of the positive impact he has had on me, many years later caught me by surprise. Why did I think of him? I just continued to realize his contribution. He thought he was teaching shop however he was teaching much more. Without a doubt, you are having that same impact. Your teaching techniques, production and applied electronics are all superb and admirable, however, you are also presenting a way to think and behave. I have nothing but praise in that you are elevating the world around you, something I wish to do.
Thank you for your kind comment!
I like the backstory with the "nicotine brown" paint colour. Reminds me of "fake plants", "artificial wood grains", "air fresheners", "fake christmas tree snow made of asbestos", "highly flammable patent leather", and vintage tiny hotel rooms with completely mirrored walls directly opposite of the entryway. Hammertone black, or even a dark hammertone grey would suit the case well.
I love how your meter says "OUCH" when you turn on the iso-trans @33:37 :)
I was about to post that comment! Same thing at 1:16:29 .... I wonder why...?
Must be some kind of warning that it senses high voltage or something...very kewl though :)
and 1:03:16
were reading OUCH amount millivolts here... I don't think that's right... I also says ouch @1:16:30
I noticed it multiple times so I looked up its manual and found out it is another name for overload or open line or even short same as if your multi-meter would show when it showed open line or short as OL in things like capacitance
One more tip on permanent markers (Sharpies). I have found plain isopropol alcohol works quite well getting it off. And it doesn't damage most paint.
denatured works great as well. Long as it's not on shellac, it shouldn't affect the paint, but I would certainly test it first!
Some cologne and perfume works well on it, probably because of alcohol content
I learned more about electronics by watching a few of Mr. Carlson's lab videos than I did in two years of electronic school.
This unit was in such good condition because the hum drove the techs crazy and they shelved it. Novice engineer designed it to look nice to the eye not really to work nice. Paul never ceases to amaze me with the info he has. Thank goodness he is sharing it with us. But I do have one question after all these years of watching. How does Paul manage to have such well manicured fingers?
He gets a manicure! And with all the work with his hands on video, it is very much appreciated.
It is a privilege to see how Mr Carson sets about identifying faults and repairing these pieces of equipment. The breadth of theoretical knowledge and practical skill are wonderful to see and a great example for anyone contemplating a technical project of their own.
One of the fastest to pass 2 hour videos I've seen, great work, going to be binge watching from now onwards. Thanks for sharing, you're a natural teacher.
Right when I need to walk out the door Mr. Carlson releases a new video. Gotta cancel dinner, this is more important!
lol :D
Hi Paul I have a scanner that is stuck in A.M. it won't switch to F. M. and the squelch is not effect ive if I turn the squelch which trim pot is the squelch?
17
Thanks again Paul for another great video. You took the tracer from discovering the problem to re-engineering the solution. Now I am looking forward to your next Vedolyzer episode.
73,
Ski
WOW!!! "The HEART of the ART"!! FANTASTIC VIDEOS!!!
Mr. Carlson, I find your video so well descriptive that when I am watching one, it keeps me on the edge of my seat "more" than if I was in a movie theater watching a world renowned thriller "or" who-dun`it!!! Your analytical skills combined with A++ Communication are truly "The HEART of the ART"!! FANTASTIC VIDEOS!!!
Best presentation mr Paul. The audience more addicted to your video. Thank you!
Thanks Roy!
Screen grid tubes are relatively insensitive to plate voltage variation. That's why you can get away with ripple in the plate supply. They're basically a voltage controlled current source. Nice vid!
I love that color on the case! Reminds me of the gear we used in Vietnam back in 1971 in the Landline Teletype hut, we had amplifiers for the machines that would pickup our machines, boost the signals and send it many miles to our daughter units. The signals needed to be strong since they were all encrypted using crypto gear.
Sweet ! I am glad to re-arrange my schedule around Mr. Carlson ! Good Job !
This is matching up nicely with my vision of the future. We have to join with the glass blowers,
Mister Carlson good morning and Thanks for the share I'm learning many things about the tube and the " tricks " in repair and restoration !!! Your knowlege is very precious for me !!! please continu your works and the videos ... Your lab is fantastic ( a dream for me ) Sorry for my Englih but i'm a low level tech and in France at my age ( 60 ) never we learn you langage ...( except by myself ...)
Very Good day Mister for you and your familly (Eric from France in Normandy )
It always like I've been at college level course when I spend time at Mr. Carlson's Lab! Thank You Mr. Carlson for all the time you send here with us, I'm sure I speak for us all in thanking you for all you've done for us here! When I get ready to tackle my '36 5 Band Philco Floor Model 116x this spring I'll be thinking of you the whole time. My Variac has arrived along with the sockets for the light bulbs (along with the 2 60 watt Edison style bulbs just to get that "old time radio' feel!). All that's left now is the isolation transformer design. There I'm having to improvise. So, what I've done there is get as many COPPER winding ONLY transformers I could get (I've got 8 so far) from old microwave ovens. 6 are from 1200 watt + ovens and 2 are from 800 watt ovens. From all I've read I have found that If I go from the 120 volt to 2000 volt windings and back down to 120 volt again I can still get the desired isolation. I know I'll lose a bit of amperage each time so that's where the extra transformers come in. If I use pairs of equal power inputs and outputs each time and keep the neutrals correct each time I'll then end up with several matched transformers all outputting 120 volts, all in parallel with about 4 to 6 amps each time, but with the ending total amperage around 12 to 15 amps. Once that is done I'll be ready to take on my radio. As the saying goes: Wish me luck! If somebody sees any flaw in my design with these transformer concepts I'll gladly accept any suggestions. Cheers!
You're welcome Tim!
As already mentioned, you are the Bob Ross of electronics with a different palette. Love your videos. Thank You.
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Since I watched the entire video, I think I understand why you didn't add a fuse to this piece of gear, but I think I would have preferred to have done so. You know, if you produced 100 videos per day, I would still be wanting to see more....you do such an excellent job. I think one of the things about your videos I appreciate the most is that you speak so that beginners can easily understand important principles, yet it isn't "dumbed down" too much for advanced and more experience Electronics Techs. Thanks for your excellent work.
What a very nice documented repair Paul. Your style and presentation was just perfect on restoring this old bit of history. One day I can only hope to be as good. Thanks as always for sharing your knowledge.
Thanks for stopping by Buddy, and your kind comment too!
phenominal paint job really kudos it looks great.
I really like the eye watt shadow thingy, especially the turquois color. Wished more companies would go retro and go back to these exterior design styles.
Great lesson, Paul! Thanks! I guessed 0.7V with the parallel caps and 0.04V with the 820uF added. Not too far away. I learned a lot!
The top of the chassis gave me a headache as soon as I saw it. What the heck were they thinking?! Thank you, sir, for another amazing video.
Nice orderley layout - no thought to function.
Wow! Mr Carlson has produced a truly awesome video here. I love all the tips and side notes along the way. Absolutely no problems with the length as it's easy to stop and continue where you left off. I have to say that my favorite topics will always be old time (vacuum tube related) test equipment repair and renovation. Thank you for your outstanding high quality educational content Paul. - Dave
That's what I call brand new used. This was a sweet video on the how to's of electronic repairs and upgrades, always worth waiting for the next video.
whenever i get old kit with the cord chopped off its because some sensible tech has cut it off as it needs recapping or other repairs, it just stops muggles plugging it in and killing it.
another reason is live auctions, here in the uk if an auction house sells a lamp or scope or other electronic kit it should be "PAT" tested if it has a power cable, so they chop them off it saves them money and ensures a qualified person will at least have to open it up to re-cable it, well thats the theory anyway.
@@Willam_J I hear you, possibly the more we politely inform people about electrolytics, powering up old gear without a speaker load, and the fact that a lot of it was built in a time when wall power was lower... It just seems that the human thing to do is plug 'er in, hit that power button, and see if she lights up.......or fries!
I always look forward to your videos Paul. I love this style video (seeing some of the work outside the lab, very cool!). 73
Just wanted to say I love watching your videos as I do a lot of engine building it's great watching something informative and not what I usually work on 👍
48:24 you made my day. Literally crying out at the screen in the last shot, "But you could just move the cap, please don't leave it". Heroic sir.
This is absolutely fascinating, worth the 2 hours of time to watch it, I learned an awful lot. Thanks Paul, The Sparcarlson is a pretty nifty tool.
you must be awfully good now than before :
The Scope Plus 440 says “Ouch”! That’s a cry for help if I ever heard one!
VERY interesting Paul, especially the twisted filaments story. Many years ago I was an electronics tech for the RAF, mainly on radar. On leaving I went in a completely different direction but watching your channel has rekindled my enthusiasm.
You are obviously very knowledgeable and passing this information on in an organised manner is another great skill you possess. Thank you for your time and knowledge.
Happy to share!
Everything's simple when your a genius Paul! Great work man! Beyond great!
My guess is that this design was from end '60. I have repaired all sort of audio and clockradio's in the thousands in the '70 (for a company), all manufactured in Asia; Japan, Malaysia, Taiwan, Singapore and more (Nothing from China yet, although China thinks different now about Taiwan). Every device, not one excluded, was fitted with a shielded power transformer like the one we see in this design, even the brown lacquer is the same. I speak about more than a hundred different designs.
I think at the time it was presented by the transformer manufacturer as a 100% solution, but was not.
I have rarely seen such transformer die, but the problem they can have is that the laminated core starts to hum mechanically. The simple solution is to put a plumbers pipe wrench in every of the 4 corners when warm, and squeeze as hard as you can. This technique has never let me down.
I am going watch the rest of the video, I am only at minute 13...
Erik den Houter It’s sometime possible to produce a canceling magnetic field individually for whatever component is suffering. You basically make a space coil of a few windings, and power it through a VR from the filament winding. Then manipulate the coil and the current setting until the hum from that one part of the circuit is gone. The. Replace the VR with a fixed resistor. This method can be applied several times, although the fields will interact somewhat, so it’s somewhat time consuming but can be made to work. It works quite well in tight designs where it’s impossible to sufficiently separate the circuits from the transformer. A LF magnetic sniffer probe will allow determining field orientation, strength and uniformity before committing to any particular mitigation. Then of course the problem with coupling between nearby transformers is that it can well be nonlinear, so you may end up having to add some saturable material in critical places to produce the right harmonic mix that cancels out the nonlinearities. It’s not a generally applicable nor even practical solution, but I’ve seen very tight transistor-era circuits that had several space coils that mulled out the field produced by the transformer. Such circuits are hard to troubleshoot, since addition of any major conductive loops alters the field and reintroduces the hum. The one I have seen was a circuit for aircraft use and ran off 400Hz AC. A few slivers of permalloy, seemingly randomly placed, acted as saturable cores. Someone must have spent a lot of time tweaking it to cancel out nearly all the hum.
Awesome videos you create. ❤️ I don't think anyone could possibly explain your troubleshooting and re-engineering techniques better than how you explain all of this. How you say you can go on about everything that is really going on is so true.
I remember as a TV technician, one of the instructors pointed out an interesting item when we were introduced to PWM power supply technology. In the front of the power supply, you first have your full wave bridge rectifier with your typical 4 diodes. Paralleled across each diode is a small ceramic disk capacitor. We all have seen them and never thought much of why they were there. As you mentioned, ceramic disc capacitors very rarely fail. I've never seen one of them fail in this application either. Well, this instructor told us the purpose of them. They filter out "silicon radiation." Basically, it was explained that just like any switch contact or relay contact, you'll have an arc spike generated. This ends up as an interference getting through and can appear as thin lines in the video. So, as these rectifier diodes are doing their switching 60 times per second, you'll generate "silicon radiation."
As far as "AC hum," we were taught that 1/2 a volt AC ripple
or less was acceptable in TV power supplies.
It's these little engineering items that make electronics such a complex technology. I don't believe that there is one person in the whole world 🌍 who knows everything about electronics technology. Especially when you consider all the various areas of electronics such as communications, RF transceivers, radar theory, optoelectronic technology, electro mechanical technology, automotive electronics, and so on. Some of the way they have made mechanical sensors. One that comes to mind is these small weight measuring digital scales. They are interesting when you look inside of one. I think they use a physical precision machined resonant tuned tank circuit, and the slightest distortion or bending of the machined aluminum block causes a change in its resonance??? It's amazing that it is so basic looking and relatively durable design. Maybe you can give insight sometime of how those sense weight also how they use other sensors like optical shaft encoders for rotation position in electronics.On the principle of how those scales work, that was my own theory and is subject to being wrong! LOL 😆
I'm sure you know this and may even own such equipment. Some audiophile people who are into high-tech home stereo systems actually use mono-block tube amplifiers in their systems. They provide a lot of current amplification to drive bass 🔊 speakers well. I was told that tube amplifiers have a type of distortion, maybe harmonic? It's inherent in tube amplifiers, and it happens to be pleasant to the human ear 👂 This is why tube amps sound good. I saw a system at a customer's house that I was working on their big screen TV. Off to the side corner of the living room was this fancy waist high table. It had a glass or acrylic see thru box on top, housing this mechanical mechanism all shiny brass (looked like gold) and polished aluminum pieces inter-mixed in the assembly. It was a $20,000+ turntable! (Record player, lol 😆) All high precision metal parts and a really intricately desigcounterweightight system for the needle land weight. It had miniature steel cables for some of the design, probably stainless or nickel metal. This thing looked like it belonged in the Smithsonian Institution!!! The woman customer said,"Yeah yeah, that's some of my husband's crap!" 🤣😅🤣 Then asked if I needed her to move one of the mono-amps away from the TV while I worked on it. I said, "Yes, please, that'd be great!"
Because I sure as hell didn't want to be responsible if anything happened to it. Stuff like that, you don't even want to touch it, just in case something happened to go awry, even though it had nothing to do with you.
Experience! That is also how we learn electronics is mostly experienced from others, such as here in this great video!
👍 👌👍
I'm enjoying The new series, so cool I really dig the resterason videos. I have robotnight almost every Saturday night,and I'm always watching your restoration videos. thank you Paul, for mr Carlson's lab
In a previous life, well previous job so to speak, I did gunsmithing. We used a bead blaster to prepare firearms for hunters who wished to have a mat blue finish. To keep the finish from being damaged after bluing, before putting them in the tanks, we did the bead blasting, then followed with a medium steel wool dipped in kerosene. This had a tendency to knock off any peaks that were let over from the bead blasting and insured that a rifle barrel getting bumped by the dash of the pickup did not show the bump in the mat blue finish. Leaving out that step did result in some bring-backs of rifles after the first or second hunting trip because such "bruises" showed up in the nice mat finish.
Beginning engineers do the same thing in vehicles, I can't describe all the silly and avoidable problems some kid with a computer and a degree can create. However, if everything was perfect right from the factory, I would never have had a career fixing problems.
You show me all the things I need to know about circuit design, stuff nobody else talks about.
Vehicles have so many electronic controls, you must have some experience with electronics to troubleshoot systems.
Many older mechanics retired when carbs were integrated with computers, I had to learn the systems, there was no way around it.
Most mechanics today are not mechanics, they just replace parts til the problem is found, and this is at the customers expense. I don't know how they get away with it, no wonder the oxymoron "Honest mechanic" exists.
I am an Honest Mechanic, not many of us left.
Your videos are totally kick major ass Mr. C. No doubts about it. Absolutely top notch. Please keep them coming.
Isopropyl alcohol does a good job removing permanent marker if it hasn't been on the paint for years. For marker that has been on paint for years or decades there is a product called write away graffiti remover that works very good. I used them all the time to remove permanent marker from medical equipment (hospitals love to write on rental units.)
Perhaps the marker ink you are removing is not as permanent. I have tried to remove 10 year old Sharpie brand black ink with isopropyl alcohol. It takes off about 80 to 90 percent of the ink. That final 10 percent is soaked into the paint. Acetone will get it off along with the paint. However the red and blue Sharpies are the easiest to remove with alcohol alone.
as I said "if it hasn't been on the paint for years"
Very well explained and demonstrated, making tracing problems with old American Radios using such design compromises "back in the days." Showing how expensive added component costs would have made the radios and Test gear prohibitavly more expensive and retail prices would have required to follow. Replacement with modern affordable components and circuit changes made a huge change. Of course Mr Carlson has a professional mindset, knowledge and ability to produce enlightenly usefull videos that many of us find very useful, Thank you.
I have been studying electronics my whole life and have been getting more addicted to your channel every day, I just want to pass along my apreciaction to you fo sharing your knowlege with us. I am so happy that there are people like you out there that have such a vast amount of knowlege in what they do,its mindblowing. I've noticed that whenever humans accomplice great things they like to give aliens or diving intervention the credit for it,when in fact its people like you that build the pyrimids or get us to the moom,anyway I hope you understand what I'm trying to say,thank you sir Im a tru fan even though I understand most of what your saying its fun to try haha.
Such a cool and informative project. I'm living vicariously thru you. 😁
Another great video. Now you have me inspired to get to that T-3 sitting on the bench waiting on restoration --- and the Mr. Carlson Probe - Albert
This is an education, I've learn't so much from this video. You've covered so many subjects.
э😎😤🤓☹️👍☹️👍☹️
Don't know how I missed this one Paul! Looks great with the Carlson touch, like the tube spotting @ the end. TFS, GB :)
I can't say that I understand much about the electronics side, but it fascinates me nonetheless. I can say with certainty that the refurb looks absolutely stunning.
Mr : total respect and respect total well done !!! a great lesson and thanks for that .... you are the best on YT !!! at 61 years old i'm learning with you ... sorry for my american langage but i'm living in french country ....
God bless you and your family Mister and Merci for the share ... Eric from France ...
Hello Eric. Your writing is just fine, I would never know you are in France. Thank you for your kind comment, I appreciate your feedback!
You've taught me so much ! To show my appreciation, I will be signing up on Patreon ! Not sure what level yet, but what you've shown me in this video alone was worth way more than $20 ! Thank you !
Welcome aboard, and Thanks!
Sir, with your knowledge of all those audio engineering quarks, like ceramic disc capacitors being micro-phonic and some of the other items you mentioned, you would probably make for an excellent audio engineer at companies like, Nakamichi, Proton, and Bang & Olufson !
Great knowledge and great videos! 👍
I was checking emails and wrapping up personal things after getting home from work, eagerly getting ready to head to my "lab". Suddenly, up pops a Mr. Carlson video notification.
Hmm, Almost 2 hours? On a signal tracer? That has to be good! Well, I guess that Atwater Kent 20c can wait a while longer. (Darn you, Paul Carlson! Get off my lawn!)
Thanks Paul, for another really good video. I'm an old timer who cringed a bit when you strapped that big capacitor to the diode. I had a feeling what the result would be, though.
I never fail to learn from your videos and appreciate the effort that you put into narrating, recording and editing your work. Producing quality videos is quite a task in itself, regardless of content.
You're welcome Tom!
@@MrCarlsonsLab The audio and the video quality is superb. I was wondering how you could shoot those videos in so dim a light and get no noise. Now I know. But I'm still curious about the editing software.
That is such excellent tutoring, thumbs up Mr Carlson, you pay great attention to details and pass on to others, valuable info for the younger generation as the old techs sadly pass together with their wealth of knowledge :-(
If I may add a small tip on how to greatly reduce the magnetic stray (and resulting hum) to the output transformer and output tube would be to cut a shield out of 1,5-2mm steel plate, wider and higher than the power transformer and an angled off long flap at 45degrees on the right to also shield off the output tube. This plate can then be fastened to the power transformer with double sided tape to ensure that there is an air gap.
I know it is a bubble gum bodge rework for a design flaw, but would save relocating components on the chassis. And it works pretty well, back in the heyday we repeatedly had those little Philips Philettas come in wth a totally screwed up and crooked magic eye, it was because of the close proximity of it to the mains transformer and loudspeaker magnet would magnetize the green screen to a point of no readout. The installation of a shield and de-magnetizing of the tube solved the problem on all of them forever.
Best regards from Germany
Unfamiliar with curve tracers after switching my electronics hobby to computers; but, 50 years ago I made something from junk box parts from a vintage electronic hobbyist magazine article. The "Octopus" circuit was reportedly common to find in consumer electronic cabinets for onboard testing. I had my contraption near an oscilloscope when a friend brought his solid state reel-to-reel stereo tape deck for repair. One channel worked; the other was dead. I wondered how fast it might be to find any fault with that thing. Comparing the trace of components in one channel against the faulted side a transistor on one channel did the same trace as your diode here. Ha! Took about six minutes. I replaced the good transistor and the bad one with a matched pair. The deck was still doing well when I left town for a new job. The thing I liked about your design was that you turned an octopus into a curve tracer by adding a meter circuit and a meter. My octopus never even made it into a case and except to satisfy my own curiosity I never needed it again. I'm not going to build one. However, I am going to look up your curve tracer circuit right now just to restore a great little memory.
Thanks for a very informative watch on a quiet day off in my working week. I learned over 10 new things about vacuum tube technology i never knew!
Ah, I am a bit long in a tooth, and I remember these... the screws were as loose as my tongue, and they originally came with a carton of Camels... those were dangerous times... one morning after too much extra caricature activity, I woke up with one digit missing. The ex swore up n down that a strange creature broke into the house and removed said digit, but didn't touch anything else... But now that I reflect upon the matter, it could have been a lot worse, if you know what I mean. I must now go join your patriot page. I have many questions for you. Always a pleasure, and looking forward to your next vid. Thanks! Learning so much and please don't take this personally, but your videos put me to sleep fast when I need it. Thanks again!
No Sleeping!
@@MrCarlsonsLab Now that's funny! I usually don't sleep because I'm watching one of your videos for the nth time and taking notes. But eventually I get that weird sleep deprivation lsd stuff and I must recharge the old battery. But like I said earlier, I need to go join your patio page, so get a hold of yourself and just be grateful that you still have all your digitals. Ha! Catch you later alligator clip. 🤣
@Full Wave Recked
Took me a while to work out that you meant "extra curricular" activity (Unless of course you draw cartoons). Looking on the positive side, even with one digit missing you can count up to 256 in binary or 262144 if you also use your toes.:-)
@@TheSharkey22 yes. A ply on words. Word. I'm trying to find like minded folks local, but haven't had any luck. Will not give up. Thank you for taking the time to respond. I appreciate it. Keep in touch.
Picture Nixon waving the duellin peace signs, and now hear th his... "I am not a cartoonist"... ha!
This is one of the most amazing channels on UA-cam
wow, that star ground trick hits me in the same way as when the engineer i was working for in high school told me that when recording, you move the microphone to the point where the sound source sounds best.
"the important
thing
is
the obvious
thing
that
nobody
is
saying."
-bukowski
I have a EICO 360 im about to restore. This has motivated me to move it up more on my project list 🖒
Stark made really good equipment. I just repaired a Stark 10-A signal generator which when I put it on the frequency counter was amazingly stable for a Colpitts oscillator. They made a lot of electronics for to Nato specs for the Canadian military. I also have an excellent Stark tube tester which I believe was made under license to a Hickock design. Hickock tube testers were top of the line.
One thing I missed in this video was that you showed what change it would make to the hum in the speaker by rotating the output transformer 90 degrees to the power transformer.
But the case and speaker grill really turned out nice.
Awesome video mr Carlson and even better restoration big thumbs up 👍
I spent my career digging holes as a construction laborer and retired early pretty much wore out. Finding your channel and others like you passing on your knowledge is inspiring. I feel like I'm in my own private shop class just soaking up the information like a sponge.
Wow! Thank you.
Welcome aboard!
Excellent!
I never knew about the internally-twisted filaments before now :-)
13:32 "But looking nice and working properly are two incredibly different things ..." - I could say that about my wife
I'm so glad you fixed the transformer layout.
Great video Mr. C! WOOT WOOT! I plugged my guitar into the RF input of my Eico 147A and it sounds pretty gnarly...
It was the end of quarter production......"Gotta make revenue....SHIP EVERYTHING!!!"
Good point about discharging capacitors. I opened up a faulty 5V switch mode power supply that had been disconnected from AC mains for three days. When I picked up the circuit card I got quite a nasty shock. The 82 microfarad input smoothing capacitor was still holding over 300 Volts! (I'm in the UK - around 240 Volts here)
There is one CNC power supply that holds over 300 Volts for weeks, if not months being disconnected. Don't ask how I know that.
Not that safety was a high priority in those days, but maybe the hum from the transformer location was deliberately allowed to remind technicians that the tracer was still turned on?
I always like your videos, there are not many youtubers that can make a 2 hour video I watch to the end.
Being made for audio trouble shooting I assumed the Watt meter was an input for an audioamp (dummyload/powermeter) Funny because I have an old AVO CT38 VTVM that has a powermeter too. Being a VTVM I assumed that it was something to measure the power consumed by a DUT (like your signal tracer) but this it turned out to actually be a dummyload/powermeter. That proves it, assumption is the mother of etc..... :-)
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My first working electronics project was an RF/AF signal tracer on a self etched PCB from an Elector schematic. I still have it. I used it a lot way-back then (1980's). Nowadays I repair industrial electronics, testgear and calibration gear for a living and that is not something you need a signal tracer for. About 10 years ago I made one from an old ham1940's HAM magazine. It had auto switching between RF and AF and a magic eye as optical (signal strength) detector. Did not use it, was just for the fun of building.
If you are interested, on the bottom is a link 3maart1946, if you click that you get the pdf copy from the magazine article. It is in Dutch but the schematic will probably be enough for you.
www.pa4tim.nl/?p=1332
Dang. Paul, I've been scratching my head for months wondering what the heck the "current transformer" is for in my Eico 147A. Staring at the schematic for hours didn't help, but after this video, I can stop scratching my head, and for that I profusely thank you... the bald spot should grow back soon... thanks!
The ripple voltage on the filter cap is proportional to the charge consumed by the circuit during the cycle divided by the capacitance, so multiplying the capacitance by 3/2 like you did will multiply the ripple voltage by 2/3 (which it did).
Using a full bridge rectifier will cut the cycle time in half, thus reducing the charge consumed per cycle in half and so the ripple voltage would be cut in half as well.
That was the best explanation I've ever heard on tubes cooling off and discharging the capacitors as much as the tube will allow. Very well done.
do you know what would be great for finding that hum? a signal tracer.
Another great video, Paul! I really appreciate your schematic walk-throughs as that, for me, was the hardest thing to learn about electronics. 40 years after taking my college electronics courses it's all finally coming together thanks to you an your videos!
Paul, very informative video on a simple ( I thought ) piece of test equipment. The explanation of the different components in an audio circuit was very good. I learned a lot of things I didn't know. Thank you for being so thorough for us laymen to understand.
Dave
Hello Mr. Carlson, I am a wanna be electronics enthusiast. I am also, totally blind. I do have light perception, and I love all things, antique, mechanical and electronic. I own to wind up, phonographs, and hope to get my hands on an antique radio at some point. I know that there are blind ham, radio operators, but is it even possible, or wise, for a blind lady to get her hands dirty on the workbench messing about with all the electronics. Is it even possible for us to fix things like this? It did, however, make my heart sing to hear the words audio oscilloscope. I.e., the signal tracer. We are currently restoring in this video. Thank you for bringing us along with you. My vote for the new color, would’ve been a nice, dark, hunter green, but I see why you went with black, for the white face of the machine.
excellent video!!!!!!!!!!!!!! you are an incredible teacher, thank you!!! mike
Another ROCKING Video from Mr. C
Can't wait to see what the "Carlson effect" will do to the prices of these Stark units ;)
You have noticed as well I see...
" Carlson effect " LMAO good 1 ! XD
I do not think you know the real Carlson effect. The simplified version is the one you are referring to. The real version is:
1. Carlson corners the market in his hidden underground layer
2. Carlson renovates one item in storage
3. Everyone goes crazy on auction site
4. Carlson's listings on auction site sky rocket
5. Carlson apparatuses across the globe reinvigorates the tech industry, one boy at a time
Funny you mentioned the Carlson effect... i commented to Shango066 once about his effect on prices too. Specifically the GE world radios. After his video, the prices shot up for a while on Ebay. Shango responded "i just wanted to point out a good radio" meaning sensitive. Just shows how large they two guys audiences are. Pretty neat.
@@franklynpolster8949 I would love to see these guys sit down around an old TV and work together on one just to see what would ensue. mr. Carlson would probably wind up macgyvering together a device which manually changes his mind.
Wonderful job the signal tracer looks BETTER than a new one
Thank you for another very interesting video.
I am looking forward to you working your magic on this piece of equipment.
I am very much more at home with valve technology than solid state.
besides my hands are not steady enough to solder solid state stuff now.
I was always told that if the power cord is cut off, then definitely do not attempt to fire it up until all the electrics have been checked, as it most likely has an electrical fault,- shorted power transformer/main filter capacitors,ect.
That unit seems so useful, that even in 21st century, I want to buy it. :D
I just have no space... and time. Thanks a lot for sharing yours!
A good demonstration of the fact that in guitar and microphone preamps, input stage resistor quality is more important than transistor quality as far as hiss is concerned.
Transistors and ICs are often berated as being hissy in such circuits compared to tubes, but the real reason is that the tube typically has no current carrying resistors to the grid, which is at 0v. The transistor being an 'enhancement mode' device requires base bias of some kind to work, and that is where the hiss comes from if poor quality resistors are used. .
Beautiful Hammertone and amazing piece of test equipment. I have to admit I would have been dubious from the start if it was anyone else attempting this.