Відео

Thanks. Glad you like the list. Thanks for the comment.

Hi. You are welcome, glad you found it interesting. Thanks for the kind comment.

Thanks for the note. I did need to take deep breaths from time to time.

Thanks for those points. Yes, for those inexperienced, the use of an isolation transformer is one of the most overlooked essentials and is difficult to find correctly set up for a tech bench. Those for medical applications still pass through the ground/neutral and therefore do not do the type of isolation needed without modification by someone who knows what they are doing. In looking at my situation you will see I placed a foam insulating tube over the exposed post in the middle back of the bench. The other metal points higher up I can manage. In addition to everything on GFCI I have lots of current limiting as well for DUT. The bench top does not have metal railing under it so I have not had any coupling issues thus far. When soldering, the soldering pencil stand comes down to the bench top so I do not park it overhead when in use. I am definitely space limited so access behind is not possible for me. Thanks for the comments.

@@PracticallyFixed , I don't work on vintage AC-DC transformerless radios, and I'm retired from Audio repair now, therefore on whatever projects I do on my own, an isolation transformer isn't strictly necessary, but if I was working on such radios or using an oscilloscope a lot then it's really a good idea to have one if for no other reason than to prevent blowing up sensitive equipment (including vintage VTVM's). By the way, I've noticed from watching UA-cam videos reviewing modern digital soldering stations that are "clones" of the more expensive pro-grade stuff, some of them leak fairly high voltage at low current onto the tip and could cause all kinds of weird behavior with associated test gear or perhaps damage sensitive IC's and components. One guy opened up a Yihua desoldering station to find that it switched the neutral instead of the hot and had all kinds of other construction and design errors built-in.

Isolation transformer was front of mind as I am about to work on a true hot-chassis set, without even the (now failed) capacitor isolation. Fact is, none of the videos here or elsewhere are instruction of fundamentals, including safety. I don't know where younger or inexperienced folks get the fundamentals these days as I believe classes on this in public schools are long gone. Being raised by an engineer "helping him" with tube gear (including TVs as we all did) as a kid, and then working in the R&D department at TI as a teen I picked up most of my initial training then, which of course continued in my working life (also retired). Newbies need an "Elmer", as in the ham world; I have never seen adequate instruction in fundamentals on any channel here. Just no substitute for an old hand looking over their shoulder and correcting someone as they are making an error. As mentioned, these videos are intended for just entertainment for folks like me who enjoy watching folks puzzle through troubleshooting and how to use logic based upon their understanding. I am trying to give back by videoing my own projects. Interesting point about the irons (I think I saw that video you mentioned a while back). Perhaps I should open mine up and take a look. Have done a lot of work with it and haven't damaged anything yet (have been using this unit for about 15 years), but you got me interested. Saw shango do a review recently of a station which created noticeable RF interference for him; my soldering station does not do that to a noticeable extent, but my relatively new hot air station does. Wonder if FCC relaxed their regulations to facilitate all these lower cost switch mode power supplies that are everywhere now.

@@PracticallyFixed , I don't know if the FCC specifically relaxed regulations on RF emissions or if UL safety codes have been watered-down ----- but with so many people buying "cloned" or counterfeit equipment directly from Asia, basically they get what they get because there is little to no regulatory oversight of such equipment. If you watch Big Clive's channel, he frequently does teardowns and reviews of equipment that turns out to be highly dangerous. But anyway, younger generations typically don't have the chance to learn electrical and electronic safety until they make a major mistake which they might not recover from. Learning to use power tools as a kid in the late 60s, I discovered what could happen if you were using a metal cased, ungrounded power drill while standing barefoot or in damp moccasins on a concrete slab floor in the basement or garage. Our schools had wood and metal shops,, auto mechanics for the gearhead types (wasn't my thing), and an electronics shop.. We subscribed to Popular Mechanics, Popular Electronics and other similar magazines as kids, so we were always reading about electrical and electronics projects that you could do yourself. In 1970 or 71 my dad, my younger brother and I partially gutted our cottage at the beach, rewired the electrical, improved the plumbing, and changed out all the windows and put up new paneling. I got zapped a few times by the power tools and I was much happier in the late 70s and 80s when double-insulated Bosch and Makita tools came out that didn't need grounding and wouldn't shock you through the plastic casings. Nowadays, of course, the prevalence of cordless tools makes both pros and DIY-ers even safer. Also, as an amateur guitar player, and still amateur all these years later, we all found out the hard way that playing guitar while standing on a concrete slab could zap you because the strings were connected to the chassis of the amp. If you want to see videos on UA-cam where the techs are very careful to remind people that amplifiers should always have a 3 wire earth-grounded power cord, watch guitar amp repairs. The good techs are all very careful to reiterate this fact over and over, and to point out when the switch or fuse are placed in the neutral line instead of the hot line, or if the chassis grounding is done in a way that's unreliable. By the way, I posted some soldering related videos on my channel recently including a review and tear down of a $45 Harbor Freight Schneider soldering station that isn't half bad for the money (certainly much better than what I had to work with as a kid in the 60s), as well as an investigation into the crappy direct-from-China soldering iron tips that are so prevalent on the internet nowadays. It's one thing to buy a cloned soldering station direct from China, but people, especially newbies to soldering, are really better off buying name brand tips, solder, flux and other accessories from authorized distributors in the US instead of buying from faceless Asian sellers. If you skim through the comments of any soldering-related video on UA-cam, you will find dozens of people complaining that the solder "won't stick to the tip" or "falls off the tip", or "it won't melt, it won't flow"...... and of course,"what am I doing wrong?"

Hi. I cannot say. When doing some research on this unit, I did see it "somewhere" that it was important that these audio output OP Amps not be run unloaded or they could fail, and since these ICs are extremely hard to find, and the unit did not belong to me, I thought it would be irresponsible of me to not take that precaution. I do know that in general, it is something I have heard about for decades regarding amps, and the Sony R2R, with vacuum tube output amps, that I just had on my channel had an internal 8 ohm load on each speaker connection unless the speaker was plugged in. Likely the answer in general is, it depends - for this unit, I played it safe.

Thank you. ​@@PracticallyFixed

Thanks for watching. I can barely see these wires. Here is another silver mica surgery video I did for a slightly different design in a GE radio. There are other variations. Getting the right replacement caps can be difficult and if the slugs get moved around too much is can be hard to get them back. In some cases I have had to use a sweep generator to help. ua-cam.com/video/3N4JPfezTUI/v-deo.html Check out its playlist for the whole project, I think there were 5 videos covering that radio. I ended up using an expensive bit of test equipment to help me get the slugs set right. Not a simple fix. Some of the older IF cans use variable capacitors instead of variable inductors (slugs). Those do not have this problem. That is one of the reasons some folk prefer to not mess with these "newer" radios, as in late 40s/early 50s onward. Glad you enjoyed it. [edit number of parts to the GE 875 playlist]

@@PracticallyFixed Thanks for your comprehensive reply.

Shango066 has shown using the variable capacitor for finding the replacement caps when doing SMD surgery. It is probably the best way to do it. I didn't have the right parts handy.

Thanks. My first exposure to Hallicrafters was my Dad had a S-38B he took onboard ship with him during Korea. I restored it many years ago and if I recall right, it also had a gimmick to do with the BFO circuit. The Astros have been plagued this year with injuries especially with starting pitching. The team had to release a couple of really big dollar contracts that were not producing as well. Been an up and down year.

Right you are. The external wire helped a lot but the missing IF amp really makes a difference. Thanks for watching and the comment.

Hi. Yes I have done this too. I mentioned near the end that I attempted this but the variables I had did not go to low enough capacitance ranges. (guess I need to go shopping, oh no) As shown, [ 1:34:00 and 1:41:20 ] I toyed with adding capacitance in series to lower the range of the variable capacitor, but since I would be choosing between discreet options, 82pF, 100, 110pF etc., I just used the 82 and it tuned in. Thanks for the note. [edit, added time stamps where it was discussed]

Hello Steve. That is a very interesting find. The K-412 circuit (in Sams) looks very similar to the Run 1&2 version of the Atom due to the couplate (this one is a Run 3 without, but still almost the same). Looked in my RCA tube manual at the licensed RCA circuits but this 4-tube version wasn't shown. The case mold looks the same with some minor changes. What led you to finding that connection? Thanks

Hi ya Doug. Thanks. I enjoying trying to diagnose these things and finding out if I got it right. Good luck on that GE, looks like fun. Thanks for watching and the kind comment.

No, I couldn't find it either; not even one advertisement. Appreciate that you watched and the nice comment. Thank you.

Thanks. That's true about the pads. Don't have any replacements on hand. The ones I have are for cassettes and for 8tracks, neither of which are appropriate. Will keep an eye out for them. Thanks for the comment.

They are heavy aren't they? Thanks for the note.

Haha! Thanks. Yeah we had some issues to deal with but all better now. Thanks again.

Thanks very much for the comment! And also for letting us know about those sponges, good info to know.

Thanks! The O-ring substitution was ingenious. Thanks for the comment and glad you enjoyed the video.

Thanks for the note. Good luck. Do keep in touch. I may be able to give you a few tips that aren't all in the video. One of the biggest tips is the location of the motor oiler tubes which I show near the end. The oiling of the capstan bushing has more to it than I showed. Thanks again for the comment and a thumbs up. :)

Thanks. Not bad for 60 years old.

Thanks Doug! Been having a lot going on here but trying to get caught up. Had considered wood but just decided in my case it would delay getting the job done. More project vids on the way. Very much appreciate the note. Very best.

Hi Jim, thanks for the note. More to come soon.

Thanks! Glad you enjoyed it. It was a fun project.

Good meeting you too. Hope you enjoy!

Yes, it is too bad about the music, really missing in my area. Glad you enjoyed it!

Thank you for contributing that! You saw that much of the actual gear in situ still remaining when you got into the industry, and I can imagine some of the "old timers" told you all about how it was to work. They would have known when it was installed, who provided it, training and whether it was to be under wraps or not. I think the concept was inspired and the design, ingenious. Thanks again.

Thanks for the suggestion - I went back to the video to take a look. If you mean the new black power cord, it is located far from the rectifier socket. The lead from the switch that now goes to the rectifier is blue and is a solid wire and is bent away from the socket but all that is hard to see on the video due to 2D perspective - things may look closer than they are. Then I reopened the back to check that the speaker wires were not near any of the tubes and they are all clear. I am pretty sure I check those things, but a degree of complacency does cause mistakes. Thanks again for the comment for me to check it.

Thanks for watching and hope you found that detail interesting. Some things in plain sight that we see all the time and take for granted sometimes have some interesting backstories - such as town names on water towers.

Ok, ok Gord. Come take a look at what your comment and others like it caused! 😊👍 See, I read this, but it took some time. Thanks for the encouragement.

Howdy! That's some good DX'n there. KTRH used to be a 50kW channel but not anymore, so that is a great pick! In HOU we like to point out to visitors that ELP is almost exactly halfway to L.A. "The sun has ris', an' tha sun has set, and here we is, in Texas yet"

Thanks for stopping in. Cheers

Thanks very much! Welcome aboard.

Hello Jim and thank you for these interesting comments; very interesting that you recall an actual test of CONELRAD. I do not recall witnessing a test of that system, although as I mentioned we had the siren test every Friday at noon. Of course my Dad had explained it to me. Regarding the 'hot chassis' aspect of this, yes, I run into this on virtually all of my repairs and like to use polarized plugs going to the switch, if not a fuse, first as well as safety capacitors. You may have also noticed the screw receptacles in this chassis were nylon inserts as they were on the Star-Lite AM/FM repair I did some time ago. On that design, the mounting of the volume control was on an isolated floating plate and they also deep-set the controls if the knobs were pulled off. Of course, designers also used wooden or plastic cabinets and knobs - with notable exception as the EICO amp I fixed and those steel case Hallicrafters radios. Certainly agree about the relative safety of household items these days and perhaps a certain lack of respect for the danger in some of these older items. I did assist my Dad from a very early age on pulling tubes from the back of the TVs for the trip to the drug store tube tester, and learned all about draining the caps and especially the CRT capacitance - "entertains the kids" - right? I am sure you remember well before polarized plugs and wall outlets and getting a buzz off the screws on the bottom of many appliances, including radios. My Dad used to tell me to "just flip over the plug", as if, "everyone know that!" - in his generation of course, most guys did.

@@PracticallyFixed Thanks for the reply! I don't recall too much of the CONELRAD test, except that it was in the daytime and the radio dial went dead except for 640 and 1240. During the test, I vaguely recall that they talked about the system. I don't know if the test was national or just regional. It does seem that they would need to run regular tests to make sure that the CONELRAD system was in good working order. Many of the broadcast stations shut down at least one night a week. That would be a good time to test the system. Thanks for pointing out the nylon inserts. For proper operation, the chassis had to be grounded, at least through a capacitor. The capacitor could fail in a short circuit mode, creating a shock hazard. The shafts for the knobs appear to be metal. I assume that they were insulated from the chassis. The tuning capacitor is a special case. I never saw it electrically insulated from the AC line. My best friend's mother had a metal case AA5 radio in her kitchen. The dial cord had broken years ago. They changed the station by moving the plates of the tuning capacitor with pencils. Then his father bought her a new radio and this one got handed down to my friend. We took it apart and dumped out pencils and bread crumbs. We replaced the dial cord. When we had the radio serviced, his mother felt sorry that we hadn't done that years ago! We lived in the GE town of Schenectady, NY, and GE products were everywhere, many purchased by GE employees in the company store. My Dad bought a top of the line GE console in late 1954. It had a lot of duplicate tubes, and my Dad diagnosed tube problems by swapping tubes whenever there was a duplicate. Later, he bought a complete set of duplicate tubes and we swapped in new tubes to locate bad tubes. I watched him and helped him. By the time I was ready to leave for college, when the TV broke down, my Dad would ask me when I was going to repair the TV. With the switch in the neutral, the line connected chassis would switch from hot to cold or vice versa with a flip of the on/off switch. There was no safe way to insert the plug. I don't think anyone took a count of how many people got electrocuted by having a radio near the bath tub and making an electrical connection to bath tub ground by trying to change the station or adjust the volume control. On top of that, there probably were many more who got a shock but survived. Now we have battery powered radios that we can safely take into the shower.

The story on that metal cased radio your friend's family had is great, thinking of the pencils in there is really funny. Swapping tubes was a great way to go! In 1980 my wife and I bought a used RCA TV from a garage sale that didn't work. My Dad took me to a shop and bought be my first Sams Photofact for that set and we got it going - I wish I could remember how we fixed it. Although that set is long gone, I still have that Photofact folder, a great memory. Thanks for taking the time to watch the video and for commenting.

@@PracticallyFixed Regarding my comment on the switch being in series with the neutral lead instead of the hot, I do recall that Max Robinson thought it was done that way to eliminate one soldered connection in a highly cost reduced design. I got my first personal TV set in the early 1960s, a 17" Montgomery Ward portable with series string filaments. The owners bought it brand new but it broke down frequently. While under warranty, Montgomery Ward's had replaced all the tubes (except the CRT), but that didn't fix the problem. When I got the set, one tube had an open filament and locating and replacing that tube got the set working again. I didn't have to make a lot of repairs to the set, but there were a few. I do recall that my Dad and I took the set to a TV repairman and he found a broken connection in a tuner tube socket. The part that contacts a pin on a tube was broken off from the terminal. He didn't want to attempt a repair. I was able to pull out the little piece of metal, insert a piece scavenged from another tube socket and solder this terminal to the existing terminal. Another repair was needed when the vertical hold control would not stop the picture from rolling. I replaced a bad capacitor. The CRT eventually got very weak and my Dad and I replaced it. I think most of the hours on it were from the original owners. In those days, children's radios were not that common and having a TV set in your bedroom was really a luxury. I took the set to college and had it in my dorm room. The Batman program was extremely popular when it came out. The dorm lounges with TV sets were packed. I had a room full of students. However, the program lost popularity fairly quickly. With my best friend's mom's kitchen radio, she listened to one station pretty consistently, so it wasn't too often that pencils were used to change the station. I am surprised that family members didn't bend the plates in the tuning capacitor! It must have been hard to tune the station accurately.

Jim, thanks by the way for the steer to Max Robinson page; he has some interesting content and an entertaining writer to boot. I saw his comment on that solder lug and scratched my head a bit on that, until I recalled my biggest difficulty in moving the Hot lead to the on/off switch: all the commons tied to the switch terminal after the switch contacts. I usually have to add a terminal strip to move all those commons off the switch and give them a new hitching post. Perhaps that is related to his point. We definitely watched Batman, I mean Julie Newmar. I loved how the villain's hideouts were filmed at an angle to appear slanted, but no one ever commented on it. Cool show.

Thanks! Yes getting away from power supplies, routers, lighting, motion detectors, etc really helps let the radio show what it can do. Let me know how the DXing goes.

Thanks! We liked playing in Mexico City - wonder if we can play more games there! Go 'Stros - only 6 games back now! We both gained a game on Seattle.

@@PracticallyFixed Hey, there's a lot of baseball left, and the 'Stros could make it up! BTW, I lived in Houston in 1964-'65, and attended the first game played in the Astrodome. It was an exhibition game against the Yankees. Mickey Mantle hit the first homer, but the Astros won.

@@jimf4492 That's cool. My parents were there in the Skyboxes for that game as well. One of the Astros announcers was a close family friend and we knew him and his family well and we went to a lot of games at both Colt .45 stadium as well as the Dome. I even went to bullfights there and saw Evel Knieval jump a bunch of cars there, Oilers games too etc. The dome has a lot of great memories for me. Even saw Pink Floyd there.

@@PracticallyFixed Well, we were in the cheap seats! I saw one other Astros game, and my granddad took us to watch the Oilers a couple of times. You have a neat connection with the place. I wish they would do something with it. I think it's too historic a place to tear down - or just sit unused.

Yes, I agree. In 2009 authorities changed the fire code so that the Dome no longer met code and so they stopped holding events there, even though it sheltered thousands of people during the Katrina evacuation a few years earlier. To my knowledge it hasn't been used since. It was a strong source of Houston pride for so long, I hope they can find a solution to keep it and use it.

Thanks! So glad you like them.

Haven't seen any content in a while; just wanted to check in and make sure all was well. I know life can get in the way of our hobbies from time to time. We will wait patiently until your next production. Take care.

Thank you for the kind note! Yes, I have been sick with something for weeks which has left me hoarse but I am doing much better. Will be getting the videos going again soon. One project is almost complete and another is in the works. Thanks again!

Thank you kindly sir!

The IF mounts did look different to me as well. Amazing condition really. Found it at a church thrift store. Must have been kept in the top of someone's closet. No bugs either!

Hi George, thanks very much!

Hello George. I would try CRC QD Contact Cleaner from the Auto Parts store first and maybe try a little scrubbing action with a pipe cleaner if it fits. I believe the culprit is dried, dirty grease on the contacts. Other contact cleaners, if you have them, such as MG Chemicals Contact Cleaner or NuTrol are good. Let it dry well as the contacts will arc at line voltage. The phenolic wafers absorbs that stuff and you want it to dry out as I believe it will break down phenolic over time if left in there. (WD40 is flammable and will ignite if there is arcing - saw it happen on a relay contactor.) If that doesn't work well enough, now that I have opened up that switch and put it back, I would do it again to do a thorough job. When opened up, the the QD on a swab does the trick with a little scraping to help. Now that I know what to do, it wouldn't take that long and the job will last a long time. If you lubricate the yoke to the middle of the dumbbell, I would suggest an extremely tiny amount (tiny: like the head of a pin) of dielectric grease (auto store) so it won't lead to shorting out. Let me know what you end up doing and how it works - we all want to know. Good luck on the 20! Thanks for the note and if this video helped give it a sub and thumb if you haven't already, it helps others to see it. Thanks again.

@@PracticallyFixed I have some deoxit D5 and Fader. Do you think one of those would work? After watching you put it together I’m worried about taking it apart haha.

Yes, I'm just a little skittish of residue; the contacts didn't corrode, they got packed with old gunk that got dirty and dried out. I understand why you would avoid the disassembly, especially the way I was whining (ha), but I was a little traumatized from the experience as I didn't know what to do - fun like a roller-coaster - gasp. But I knew that Philco had to be able to assemble them quickly during production, so I just needed to figure out "the trick". I have another Philco of this era I will restore eventually and it has this same switch. I will take it all the way apart as I did here just see how fast I can do it now I know the trick. Just don't let the spring launch parts into oblivion! Good luck and let me know how it turns out. (c'mon - go for it!! You want to...)

@@PracticallyFixed I sprayed the tiniest bit of deoxit in and used a very small swab. Could reach the closest tab easily and took off a ton of gunk. Bent the swab and got to the far tab and also pulled off a ton of gunk. Used a heat gun to lightly dry the phenolic. Testing shows perfect ops for now where it was very intermittent and mostly not working prior. I have a lot of other work to do before I need the switch so I’ll let it dry thoroughly. If it gives me any fits then I’m going for it. Thought this was worth trying anyway. (Chicken)

@@georgescott1353 awesome. Glad it worked!

Hello. The SG165 sweeps frequencies and puts out a marker that shows on the scope for 10.7MHz, the IF frequency for FM, as well as 100kHz on either side. So 10.6, 10.7 and 10.8 MHz markers. I adjusted the two IF transformers away from both peaking at 10.7MHz, to having a peak closer to 10.6 and 10.8 respectively. That peak would be lower, however the bode magnitude plot on the scope would show a wider curve, not so sharp, such that they essentially ran together at the top creating the plateau appearance that spanned across 10.7 MHz. See 29:05 timestamp in the video. That gives a more evenly tuned bandwidth and thus I ended up with less distortion, allowing the Frequency to Modulate either side of 10.7MHz at a constant magnitude - rather than going through a peak. It is take a bit of patience and experimentation to get the right form, but the SG165 does a nice job helping. The person who previously worked on the radio aligned the FM the same way AM is aligned, which is to peak a maximum at the IF frequency which is ok for AM, but not really for FM - although it will work, but not sound as nice. I hope that I explained that ok. Thanks for watching and the comment.

Hi Luther, and thanks. I am also a native Houstonian from near the Astrodome. Yes there is a club in Houston, Houston Vintage Radio Association - HVRA dot org. On their webpage check out the newsletter The Grid Leak for upcoming meetings and events. Yearly dues are $20 and you can join on site of one of their events. Sometimes at their auctions (you have to be a member, but can join before they start) you can score some radios, etc in various state of repair and not too pricey to learn on. If you are setting up a bench, take a look at the referenced videos in my show notes on bench safety. When you get into equipment with power transformers, the voltages are much higher than on these all American 5 radios. Glad you enjoyed this series, there are several more to choose from here, just visit my youtube page and check out Playlists. Don't forget to Comment and Thumbs Up, it helps out! Good luck!

Thanks for the response! I'll join HVRA and will definitely check out the references safety videos. All the best - Luther

You are welcome. I noticed the 2nd Quarter Grid Leak isn't posted on the site yet, but check back often as it should be coming out soon. Don't forget to chip in in the comments sections of these videos - it helps Thanks