" there are no mistakes.., just happy accidents...." Your videos are my 'balm' in an often otherwise messed up world. Great series as always Tony! You're the Bob Ross of electronics restore & how-to vids.
You would be surprised! I inverted the supply on an amp three times after replacing lateral MOSTFETs in one day. Can become a costly exercise not much happiness :)
Hats off for showing your mistake, it would have been so easy to edit that out and make out you're perfect. At least it reflects real life and people will connect with that much more than the perfect world version.
The concept of touching a small amount of solder to the soldering tip is actually called the heat bridge. It helps transfer heat from the tip to the objects being soldered.
Hi Tony! Really like your channel and enjoy every video I have time in my busy schedule to watch, but I will make a couple of comments about this one. Wouldn't best practice dictate that the 120vac mains wires be twisted as they run around the perimeter of the chassis for hum/noise reduction? Also, I might suggest that your power indicator light be installed after the fuse instead of before the fuse. That way, if the fuse blows, you will not get a power indicator light and give you a hint that the fuse may be blown. Your way, the power indicator light will come on whether the fuse is blown or not and may make you think something more sinister is wrong. Just some food for thought.
Thank for the comment! Although I drew it that way on the schematic, if you look back on the video, the light is actually connected after the fuse. As for the power leads, they were run along the side corner of the chassis on the opposite side of the transformer from all of the other circuitry, so there will be no problem with hum or noise. Thanks again!
Hi Tony, Sorry for the late reply. I am about eight hours ahead of you so, when you are busy, I am resting. I guess this is a very intuitive video to the novice or DIYer, as well as teaching the young engineer some very practical things which only we have experienced and learned in our early days. I did my time as young engineer in the Post Office (automatic exchange) and learned from the wireman how to wire an MDF (Main Distribution Frame) and tie the wires together with some waxed twine, and yes that is not something that these youngsters would ever know. They are brought up on surface mount, PCBs and ICs. Fault-finding through an any entire exchange also taught me extremely well how to find a fault between a subscriber and wherever, sometimes several miles away, trough various other exchanges. You may find a dry joint, disconnect, short, relay not tensioned, dirty contacts, relay armature and adjustment out of spec, etc. There was very little to no electronics, everything electromechanical and to exacting specification. Strangely enough, the old guys then I learned from actually built their own valve amps and I don't know of any artesian, tech or engineer that did not build as in an exchange and when finished, was a work of art. Wiring looms from one end to another, different looms for power and signal, all kinds of stuff all perfectly squared off and not a single bit of hum or noise. You have just awakened memories of 50 or so years ago. I think this series will be one of your best, demonstrating that if you are a youngster, don't argue we us old folk we are in the knowing. I look forward to watching the rest of your series on this little project. Furthermore, I have also been speaking to Eddie regarding the simulation of JAT, and yes, although it is a good indication of possible analytical performance in a steady state or small signal analysis environment. However, you can step various parameters, cutting time to what took us months to do. But, at least, understood what was going on. Yet, it still depends completely on the skill and years of experience of the designer to actually get it right, knowing of all lumped constants and 0other physical constraints creeping into a PCB or wiring layout affecting performance and specifications adversely. These factors cannot be predicted by any simulator in existence, even though MicroCap is probably the best available and I have used simulation and predictive analysis in my daily work for some 25 years, but only to prove a concept. Most DIYers swear by the simulations and even argue system performance based on simulation, claiming miniscule THD at five orders of magnitude below zero! We know that everything we design and tweaked in the real world until the result consistently and closely conforms to our design requirements. Well done my friend, this was excellent.
We all make mistakes: Some UA-cam channels edit out all their mistakes, perhaps their ego won't allow them to show that their human. I appreciate your unedited bloopers.
Great job, Tony. I see you 'followed' my advice on not using the circuit board! :) A little nit-pick. the power switch's threads are exposed on the front of the chassis (providing there's room next to the transformer). (13:58)
So since the chassis is upside down, you would toggle upwards to switch on. With stainless, it a good idea to keep the pressure on to avoid surface work hardening.
On my Douk kit similar to this one I replaced the transformer bolts with brass ones and added insulating washers. This greatly reduced hum in one channel. It seems like the transformer was pushing eddy currents or magnetic fields through the chassis, and the way I built it, it was very susceptible to that (far from a star ground). Now it sounds very good actually. Probably improved efficiency too.
That's a good point about overheating the IEC connector and possibly melting the plastic and ending up with loose pins. I've found that putting a plug in the socket can dissipate some of the heat away from the pins and their surrounding plastic. That little trick works well with RCA sockets in particular! They're really prone to melting and deformation, so I always make sure I put an RCA plug in the socket before soldering the leads.
Good components are normally thermionic stable plastic (like the olden days' Bakelite) and should not melt. However, the cheap mas produced junk that is available over the counter melts at about 80 degrees centigrade. Buy terminals plugs and socket from reputable manufacturers where a specification is available. This is the first step to longevity of your project.
I've been in the game for a while and I still goof up occasionally. My DBT has saved my skin (and the DUT) more than a few times for sure. One of my recent screwups involved a razor-sharp lamp reflector, a broken dial string, and a LOT of swearing.
More tutorial series goodness = yum! I might suggest a little different workflow... Temporarily pre-fit the hardware, to be able to determine the needed wiring routes and wire lengths. Remove the hardware and solder up as much as possible. Then, permanently seat the hardware. It just means that you are soldering outside of the chassis, where you can get at things easier. Question = What is the make and model of your heat gun? Thanks!
As a second language english learner, I find your voice is very soothing and good to hear. I almost fall asleep when wathing it. Is this a bad or good thing? 😂
hopefully I got this right-some power transformers have center taps some don’t there are different ways to create a power supply however the best example would be look at a 100 W Marshall plexi power supply and a 50 W Marshall power supply you’ll see that the 100watt does not have a center tap uses a full bridge rectifier and the 50 is wired differently if you compare those you might start to understand it I’m still learning myself I hope this helps
@@buzzedalldrink9131 It looks like my question was somewhat answered in his video on rectifiers but he did not specify what high current was for a bridge rectifier. Most of the computer speakers I have seen the caps across the doedes only use the standard 1n4007 style diodes and I really doubt that the speakers would draw close to the 1 amp rating of the diode but I could be wrong.
I don't think I can post links in the comments. Google: why put disk capacitors across diodes. From what I found, older general purpose diodes had "switching noise". The caps typically 10 to 100nf, help with noise in the HF frequencies. Something to do with EMC compliance.
Everytime you said Dab, all I could hear "A little dab'll do ya... use BryllCream" Not me, but the ol' man used WildRoot. Does this have anything to do with the video? Only one of those random memories that come from working with "old tech". Thanks for the smile.
@@xraytonyb Hi Tony, In most of my builds I placed the pilot light before a fuse, and my reasoning is simple. If the amp does not work you know it while the pilot light will show you the obvious, power is available and the problem will lie beyond, such fuse.
I'm glad you decided not to use the circuit board. I would have connected the pilot after the fuse. In your case should the fuse be blown, the pilot will still illuminate.
" there are no mistakes.., just happy accidents...." Your videos are my 'balm' in an often otherwise messed up world. Great series as always Tony! You're the Bob Ross of electronics restore & how-to vids.
You would be surprised! I inverted the supply on an amp three times after replacing lateral MOSTFETs in one day. Can become a costly exercise not much happiness :)
Making mistakes is an unavoidable part of electronics assembly, so kudos for keeping them in the video and keeping it real! 👍
Forgetting to first put the cap when soldering a phone jack only happens when you just made the most perfect solder job!LOL
For me, it's flaring the best brake line flare ever, then realizing I left the line nut(ferrule) on my bench. Lol
Making mistakes proves we are human tony, its alowed to make them.
Clever, I see what you did by mispeling allowed.
Hats off for showing your mistake, it would have been so easy to edit that out and make out you're perfect. At least it reflects real life and people will connect with that much more than the perfect world version.
The concept of touching a small amount of solder to the soldering tip is actually called the heat bridge. It helps transfer heat from the tip to the objects being soldered.
I caught the boo-boo when you hooked up the light. But I figured you'd fix it.And you did so well! Great series. BTW!
Thanks for this Tony, and remember there are many beginners out here -- there's no such thing as too fundamental
You are burning you drill bit. You have to go slow speed and put pressure on Stainless Steel
A little cutting oil goes a long way too.
I agree! Tubes on PCB is just WRONG! Focus Focus, hard to look at.
LOL, we've all been there. Some of us have never left..
Hi Tony! Really like your channel and enjoy every video I have time in my busy schedule to watch, but I will make a couple of comments about this one. Wouldn't best practice dictate that the 120vac mains wires be twisted as they run around the perimeter of the chassis for hum/noise reduction? Also, I might suggest that your power indicator light be installed after the fuse instead of before the fuse. That way, if the fuse blows, you will not get a power indicator light and give you a hint that the fuse may be blown. Your way, the power indicator light will come on whether the fuse is blown or not and may make you think something more sinister is wrong. Just some food for thought.
Thank for the comment! Although I drew it that way on the schematic, if you look back on the video, the light is actually connected after the fuse. As for the power leads, they were run along the side corner of the chassis on the opposite side of the transformer from all of the other circuitry, so there will be no problem with hum or noise. Thanks again!
Hi Tony,
Sorry for the late reply. I am about eight hours ahead of you so, when you are busy, I am resting. I guess this is a very intuitive video to the novice or DIYer, as well as teaching the young engineer some very practical things which only we have experienced and learned in our early days.
I did my time as young engineer in the Post Office (automatic exchange) and learned from the wireman how to wire an MDF (Main Distribution Frame) and tie the wires together with some waxed twine, and yes that is not something that these youngsters would ever know. They are brought up on surface mount, PCBs and ICs.
Fault-finding through an any entire exchange also taught me extremely well how to find a fault between a subscriber and wherever, sometimes several miles away, trough various other exchanges.
You may find a dry joint, disconnect, short, relay not tensioned, dirty contacts, relay armature and adjustment out of spec, etc. There was very little to no electronics, everything electromechanical and to exacting specification.
Strangely enough, the old guys then I learned from actually built their own valve amps and I don't know of any artesian, tech or engineer that did not build as in an exchange and when finished, was a work of art.
Wiring looms from one end to another, different looms for power and signal, all kinds of stuff all perfectly squared off and not a single bit of hum or noise. You have just awakened memories of 50 or so years ago. I think this series will be one of your best, demonstrating that if you are a youngster, don't argue we us old folk we are in the knowing. I look forward to watching the rest of your series on this little project.
Furthermore, I have also been speaking to Eddie regarding the simulation of JAT, and yes, although it is a good indication of possible analytical performance in a steady state or small signal analysis environment. However, you can step various parameters, cutting time to what took us months to do. But, at least, understood what was going on. Yet, it still depends completely on the skill and years of experience of the designer to actually get it right, knowing of all lumped constants and 0other physical constraints creeping into a PCB or wiring layout affecting performance and specifications adversely.
These factors cannot be predicted by any simulator in existence, even though MicroCap is probably the best available and I have used simulation and predictive analysis in my daily work for some 25 years, but only to prove a concept.
Most DIYers swear by the simulations and even argue system performance based on simulation, claiming miniscule THD at five orders of magnitude below zero! We know that everything we design and tweaked in the real world until the result consistently and closely conforms to our design requirements. Well done my friend, this was excellent.
We all make mistakes:
Some UA-cam channels edit out all their mistakes, perhaps their ego won't allow them to show that their human. I appreciate your unedited bloopers.
Great job, Tony. I see you 'followed' my advice on not using the circuit board! :)
A little nit-pick. the power switch's threads are exposed on the front of the chassis (providing there's room next to the transformer). (13:58)
Yes..I've done that too...Attaching the "new" wire to the closest available terminal..."OOOpppsy Daisy".
So since the chassis is upside down, you would toggle upwards to switch on.
With stainless, it a good idea to keep the pressure on to avoid surface work hardening.
Stainless! Rayyyyy! Awesome xraytonyb!
Thanks again Tony, drilling on metals at a slow speed is more effective and lessens metal to metal friction and may preserve the bit's sharpness.
I have a kit from China sitting in the storage for more than a year. This is exactly what I need to get started.
On my Douk kit similar to this one I replaced the transformer bolts with brass ones and added insulating washers. This greatly reduced hum in one channel. It seems like the transformer was pushing eddy currents or magnetic fields through the chassis, and the way I built it, it was very susceptible to that (far from a star ground). Now it sounds very good actually. Probably improved efficiency too.
It is nice to know what you are doing. And you have the extra bits to make the switch work
She's going to be a beauty!
That's a good point about overheating the IEC connector and possibly melting the plastic and ending up with loose pins. I've found that putting a plug in the socket can dissipate some of the heat away from the pins and their surrounding plastic. That little trick works well with RCA sockets in particular! They're really prone to melting and deformation, so I always make sure I put an RCA plug in the socket before soldering the leads.
Good components are normally thermionic stable plastic (like the olden days' Bakelite) and should not melt. However, the cheap mas produced junk that is available over the counter melts at about 80 degrees centigrade. Buy terminals plugs and socket from reputable manufacturers where a specification is available. This is the first step to longevity of your project.
You never make a mistake; it's a modification or an experiment that either worked by surprise or not.
a power-on indicator is always a good idea
Will be seeing this thru to the end. Can't wait. But could u pls add the links to the series in the description too? Helps alot.
I remember changing an intake manifold,forgot to pull the toilet paper out of the ports DOH!! fortunately remembered before fireup lol
😂😂👌
I've been in the game for a while and I still goof up occasionally. My DBT has saved my skin (and the DUT) more than a few times for sure.
One of my recent screwups involved a razor-sharp lamp reflector, a broken dial string, and a LOT of swearing.
Oh yeah, I've done the same with mic connectors many a time-LOL!!!!
More tutorial series goodness = yum! I might suggest a little different workflow... Temporarily pre-fit the hardware, to be able to determine the needed wiring routes and wire lengths. Remove the hardware and solder up as much as possible. Then, permanently seat the hardware. It just means that you are soldering outside of the chassis, where you can get at things easier. Question = What is the make and model of your heat gun? Thanks!
As a second language english learner, I find your voice is very soothing and good to hear. I almost fall asleep when wathing it. Is this a bad or good thing? 😂
I tend to do the same, we're just learning subconsciously. Lol
@@Joetechlincolns Hi nice to know you here. Where are you from. Can I make a penpal with you?
Xraytonyb your Amp kit that you AR billed is cool
i didnt get the notification for this video !!!
Can a digital voltmeter read the currunt or voltage on speaker lines?
If the steel bottom is galvanized (zinc coated), you may want to scuff and paint the bottom, to avoid tin (zinc) whiskers …
You wired the light to the wrong side of the switch. It will always be on. LOL
When you get to the bridge rectifier could you explain why some amps have capacitors across the diodes in the bridge rectifier?
hopefully I got this right-some power transformers have center taps some don’t
there are different ways to create a power supply however the best example would be look at a 100 W Marshall plexi power supply and a 50 W Marshall power supply you’ll see that the 100watt does not have a center tap uses a full bridge rectifier and the 50 is wired differently if you compare those you might start to understand it I’m still learning myself I hope this helps
@@buzzedalldrink9131 It looks like my question was somewhat answered in his video on rectifiers but he did not specify what high current was for a bridge rectifier. Most of the computer speakers I have seen the caps across the doedes only use the standard 1n4007 style diodes and I really doubt that the speakers would draw close to the 1 amp rating of the diode but I could be wrong.
I don't think I can post links in the comments. Google: why put disk capacitors across diodes.
From what I found, older general purpose diodes had "switching noise". The caps typically 10 to 100nf, help with noise in the HF frequencies. Something to do with EMC compliance.
I really like that heat gun. what is the model number? Thanks.
Everytime you said Dab, all I could hear "A little dab'll do ya... use BryllCream"
Not me, but the ol' man used WildRoot. Does this have anything to do with the video? Only one of those random memories that come from working with "old tech". Thanks for the smile.
Did you want your indicator light mod to be past the fuse?
Tony, what are the terminal boards with the stand-off and spade/loop openings for point to point wiring “called”, as I’m having trouble finding them.
Terminal strips. Guitar amp repair sites and places like tube depot should be a few places to look. Even Amazon.
Sometimes turret board
I sure am not a patron long time but I need your intuitive skill to help me with my Fisher 800-b
"Errare humanum est"... as Seneca said.
Speaking of the light, wouldn't it be better to hook it AFTER the fuse so it wouldn't turn on in case the fuse is blown?
It is after the fuse.
It looks to me that the schematic shows the switch and lamp before the fuse but I'm pretty sure that Tony did wire both after the fuse.
@@xraytonyb Hi Tony, In most of my builds I placed the pilot light before a fuse, and my reasoning is simple. If the amp does not work you know it while the pilot light will show you the obvious, power is available and the problem will lie beyond, such fuse.
I sure hope you can give the amp to me. Money is tight for me.
I'm glad you decided not to use the circuit board. I would have connected the pilot after the fuse. In your case should the fuse be blown, the pilot will still illuminate.
The light is after the fuse. Go back and check out the part where i describe the pins of the iec socket.
Correct
not using the PCB ☺
Second! Wait, I mean First!
IMHO the video length isn’t nearly as important as the amount of information.
Xraytonyb this cool