How to quickly troubleshoot noise Vintage Fender Reverb Tube Guitar amp D-Lab
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- Опубліковано 30 сер 2018
- Yep, another Fender classic amp hits the loading dock of D-Lab electronics. This one had the complaint of noise plus tremolo speed. The noise was due to several microphonic tubes and a few bad solder connections. A fairly quick repair. Great quality built amp. Love working on these machines. Hope you like!
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Great video, but I agree with other posters that the tremolo is way too fast still (roughly twice as fast as it should be).
Great video, that tremolo speed is still way faster than it is on my Super Reverb. Mine goes down to as low as about 3 Hz.
I did a one year vocational on radio mechanics before solid state and transistor radios went out. It is all tubes before. It's all coming back to me by watching your videos. Thank you very much Sir. And stick with the humor. People like you are becoming rare recently. God Bless you. l like your style very much !!
"The bigger the glob, the better the job."
During my Army career, I was Ordnance Corps (missile maintenance), first HAWK, then Patriot. Three times out of four, I could say a job like that was done by a graduate of the Nike Herc School of Soldering.
Never too late to take guitar lessons! Plus it is a lot more fun testing the amp with an actual guitar when you are done.
Leo Fender never played either. He managed to make a few contributions despite that.
Another great video. I really appreciate your systematic diagnosis of these amps. It has helped me quite a bit so thank you for making these videos.
Thanks Terry!! Your videos are great, with or without the theatrics. This one is no exception and we appreciate you sharing your time and knowledge with us! I have a Super Reverb in line for repair and assembly now, so these vids are very timely!
Great channel!
Love the education an transparency, and of course the lurking humor that bleeds through.
Amazing job Terry!!! You always make it look so easy. Thanks for another great training video!! 73's John
Keep'em coming, I've already rebuilt one Princeton reverb so thanks for your help
I love the way you teach your granddaughter the basics! If she gets the bug, she will have an advantage in her life! Godd one matey!
What a troubleshooter!! Well done Terry
Always happy to see more vintage amplifier repair videos. Don't worry about your latest ones not having the gags and skids that many of your other videos have. Personally I don't care about them, but I don't mind them either.
Good man Young Terry looking after and maintaining that red wine!!! (and the amps ok!)
Thanks Terry. Another great repair!
Outstanding!! Thanks so much for this, and the last video! They'll come in real handy as I explore my Super Reverb! :-)
Another great repair Terry. You are the master and now I am pumped up to start on this Johnson Valiant this morning.
The Valiant is a great transmitter! Hope your gonna feature it on a video! Love to see
Hi Terry. Yes I agree. The video is up my friend. Found a few interesting items.
Cool deal man, I will check it out
Thanks for teaching me amp tech. I've fixed old Peavey bass heads; sort of paint by numbers, solid state. Much obelized for all the detail for squashing noise in guitar tube heads.
Hey guys, the testing of reverb & tremolo with an audio generator is not musically the best method. However for my purpose it works via oscilloscope. So, don't let that throw you. Using a guitar both functions are rich and musical. I will be posting a post review of the amp with a guitar connected.
Very nice diagnostic options. One thing though - even with headphones, I cannot hear much difference in hiss before and after... Maybe just the camera microphone not being sensitive enough - I believe the author.
Great job Terry!
Mr. D-Lab has that Quirky sort of Humor that can only be developed after working for years as an Successful Electronics Maintenance Tech (or higher).
Great videos! As a new school tech these have increased my knowledge and ability to diagnose and repair tube amplifiers which is almost a dead art. Now I just need more knowledge on the power amp series amplifiers smh lol!
The old Unger snozaramous does indeed make short work of those shoddy solder joints. So, I bought a NOS Vulcan recently with wood handle and original cloth insulation! It is a beast and works great and is a must have for me now. Keep em glowing!
Thanks Terry. This was very educational
Thank you very much for this. I love the straight ahead, no nonsense style of the last two videos. But I enjoy all your videos so what do I know?!
Great Video, I did hear some back round noise about "Ghouls" from Ghoulardi, when you first used your soldering gun-LMAO! Not to many people no who he is. Great instructive video. Made my day!
Great video. I honestly wouldn't worry too much about a slightly microphonic tube. Especially an old RCA.
i love the goulardy with the big sodering iron
Beautiful sound!
I enjoyed this a lot. Thanks for your knowledge!
Excellent troubleshooting...thank you for this video.
Love the channel, boss! You're a funny guy, thank you.
Bravo!!! Again the love of Black Hole and Lady 6L6.
Being a auto tech for 30 + yrs , I use a 4 channel lab scope nearly all day , everyday .
Do you use none- intrusive testing as well as intrusive ?
High and low amp current probes I use work well , but there are times when current probes won't work ,
Circuit boards and the like . I like the attention to detail , there aren't enough techs that take pride in the work and I admire that Mr !!!!!!
Happy scoping
The trem still sound like it was a bit fast but other than that you done a top notch job again.id love to have half your smarts.great job D-lab.
Yep, tremolo still to fast. Love your vids!
Yeah, I hate a fast tremolo. Every tremolo amp I've owned I had to slow down, if even just a little.
Thanks for this especially helpful was showing how you inject sound into the amp and monitor it thru the 4/8 ohm speaker dummy load (which I've copied)
Never see again Farfisa & Elking - Amplifier & Benson Sound System Amplifier, .... Bravo.
I thought I was having an issue with my vintage 1959 Bassman. It would occasionally build up hum, sometimes slowly and sometimes scarily fast. I thought it was just the 1959 so I switched over to the 1960 Bassman last night until I had a chance to tear into the 1959. The 1960 did the exact same thing except it was one of those fast spikes that makes you jump up to turn off the amp before it blows up. That’s how loud it gets. Then I wondered, how could I have the same problem on both amps? I don’t think it had ever happened on the 1960. The weird thing is when I cycle the power off and then on again, the hum instantly goes away so of course I assumed it was an amp problem. I’ll go on and play the rest of the session with no problems. My guitar comes out of an amp switcher then into a vintage 1964 brown Tolex Fender reverb unit. I’ve had it over 12 years now I think. The output of the reverb is plugged into the Bassman amps depending on which amp I am using at the time. Now I’m thinking there is some type of leakage in the reverb unit that is going to the amps. I have checked the blue molded caps before and they seemed fine, specifically the .1uF (2) that come off the 12AX7 to the output. One is on the cathode of one triode and one is on the plate of the other triode. They see 130VDC and 160VDC respectively. I have noticed there is quite a bit of scratchiness on the “mixer” pot. Just checking to see if you ever experienced anything like this. One of the things I’m trying to understand if it is the reverb unit is how can cycling the power off and on again on the Bassman stop the hum from coming from the reverb unit. Maybe I’ve still got another issue and that is why it is confusing right now. Not sure yet. I’ve had more .1uF caps leak in all of my amp than any other value except they were all Astrons. Now I dealing with ’60’s Blue Moldeds which are supposed to be much more dependable. I just checked three of the blue moldeds for insulation resistance on my Sprague Tel-Ohmike TO-5 and they tested fine and have not drifted in capacitance at all. Still scratching my head. Could it be the three 40uF/450V Sprague Atom electrolytics in the can? They are testing fine too. Sorry for the long question but I'm baffled right now.
It turned out to be a bad solder joint on the rectifier diode in the 1963 Fender reverb unit that I run into before the amp.
Thanks for the great video
Great video! Thank you
1st.! great repair. Back to back Supers! Thanxz
1st what?
I came to see what the Black Hole tool you used for diagnosing noise - ... - it's your wine. drink and repair, got it. (nice channel)
Привет Терри, я из России очень люблю смотреть Ваше видео. Я на досуге занимаюсь ремонтом усилителей и из Ваших уроков по ремонту узнал очень много полезного для себя.Очень хорошо получать знания от профессионала в своем деле,желаю Вам здравствовать и буду ждать новых видео.
Thanks for sharing!
Awesome. I got a good laugh out of the last few seconds.
Thanks! Just subbed
Very Good!
Nice job Terry.. What was the deal with the Red electrical tape ? Simple easy fix as always.. Ron
which V/div do you use to check the noise level? I know, that it depends on the speaker impedance ....
Hey sir! Love the channel! Love the topics, I love the life of music. I’m getting to a better point where I can afford some two vamps, but like most men I like to be able to take care of my things and service in properly and diagnose things as well. I have an old Ampeg reverberocket 12. Every once in a while, it will crack and pop a little bit, and the volume will go away. Sometimes it comes back. I noticed when I go back to check it when I barely press on the plate that all the volume and tone parts are on it’ll crackle in and out like maybe a loose connection. Do you have any idea what that connection would be And how I could fix it fairly. Simply all of my solder joints look fine. I even looked pretty close last night and I pushed on it that play on top again, and it kicked into gear and was fine for hours. I’m kind of sketched out though because it’s probably a loose connection and I don’t want it to catch fire or ruin tubes. I know you’re busy man if you could send me a reply that would be absolutely amazing. Thank you sir don’t stop doing what you do!
Have you thought about enterning the flashing lamp competition 2018 ?
Previous repair moved the power supply ground from the chassis to the brass grounding plate. BAd move, should have eitehr been left alone, or more properly grounded on a PT stud. Other things inside that beauty made me cringe. Good video though re: getting out the racket.
Nice!!
Hi great video ,if you know your preamp is not working ,and two of 12ax7 tubes out of the four are not lighting up ,should i just buy two new 12ax7 tubes? Thank you, the amp works with the guitar plugged into The loop return jack .
Damm what wattage is Mr. Snazoramous that you used to heat up the grounds? Last time I had to do that I had to use a butane soldering iron to get hot enough and I had to remove all the POTs to pull the wires out of the way so I didn't burn them.
I'm working on an original '65, have very loud 60 cycle hum. Pull the vibrato tube, no more hum. One cathode resistor out of tolerance (electrolytics have been changed). There is a .02 in plate circuit which is way out of tolerance...400 volt. Planning on replacing. Don't see how it could be the issue...but shorting the input did nothing. You seen such a thing? Most of pots are scratchy, planning on replacing all 10. The component layout sheet has value and then letter A, L, or RA....hate to assume but would that mean audio, linear and reverse audio tapers? I've had this for quite some time, developed eye issue, lost half my peripheral vision so just getting back to it. Owner just became silent key two weeks ago, would like to make it like new for his wife to keep. Married 55 years so he must have bought it right after he got married. Sent you several emails but no responses...didn't know if you were okay or not.,
I got a "snozoramis" that would knock a Bear out if you hit it on the head. I think it was made for metal working .
tremolo is a bit fast... but should be hard to know for you because you said youre not play guitar soo hard to know for you haha :) that a thing to check with someone who play guitar and really know about how is normal speed... im a musician and technician and seriously, i dont really know too what is the real normal speed haha soo dont worry its ok :) great repair d lab !
You look like you have been doing this stuff as long as me
Should we use those preamp tube shields?
Snozzeramus Ungar to the rescue!
Hi there,
I have a bandmaster (1968 AB 768 silverface) . I think it should run at 4 Ohm. The thing is I have a 16 ohm speaker already and I was wondering if it would be ok to use the speaker with this amp.
First Fender super theremin Amp!!! 😋
I have a oscilloscope... where can I connect the points of the oscilloscope to see where it comes the noise?
I picked up a old used oscilloscope it lights up when I plug it in but I don’t have any test probes what can I use can I email you the make and model number.I also have a second question do you have your oscilloscope isolate grounds
"♪ I dont play guitar ♪ "
"♪ But I can play amp ! ♪ "
It appear that transformer has been replaced by Hulk himself!
Love my ‘66 super
terry, what is the wattage of 'snoz'?
What’s the music at the start of your video?
The trem. seems too fast on slowest setting. Normal? If so, how to slow it?
So Terry,,, what was making the tremolo speed up? Normally that's a RC time constant thing I believe but I didn't catch what you finally found. Sorry buddy, I'm slow these days lol.
skycarl
I believe he determined there was no issue with the vibrato...speed or otherwise.
Perhaps the owner was mistaken???
Hey Bill,, yeah the reason I mentioned it was when he played it, it sounded a bit fast for the low setting which is what the owner said it was doing. And that's why I mentioned the RC part of it. He didn't turn it down to the lowest position so I was just wondering.
skycarl
I’m not really sure... and I’m certainly no expert on vibrato circuits for sure
He was watching it in the oscilloscope and didn’t seem to think it was a problem.
I enjoy watching his technical approach to amplifiers...
I have a lot of vibrato amps and obviously there is a “useful” range of speed...
I understand Dlab doesn’t play guitar 🎸... so perhaps when someone does it would be more noticeable???
Can’t really say.
I just know when the vibrato doesn’t work at all... which is the case on my ‘68 pro reverb... it sucks...lol
Perhaps I need to send it to Dlab.😏
I would prefer a slower tremolo, but maybe Supers are just built that way?
I thought the slowest speed was too fast as well
I have a strange and bad issue with my Fender Deluxe Reverb clone (standard AB763, self-built from a kit). It used to work great, but has recently started to crackle and noise. Problem seems to be in the phase inverter stage (12AT7 tube). One side has proper voltages, the other has a way too high plate voltage (~280V instead of 170V). Tube checks out. 100k / 82k Resistors check out (I think), 0.1 µF coupling capacitor to the 6V6 checks out. Grid / cathode voltages are the same on both sides of the 12AT7. If you have any idea how to troubleshoot or fix this, I will be eternally grateful.
Check the 1 meg grid resistors. Make sure the connections are secure. Also inspect the inverter tube socket for damaged pins
Thank you, will do!
every 1 like's a little tickle with there slap! hahaha Thx terry have a great day!! :-)
Awesome repair video Terry. I had messaged you on Reverb concerning a Hammond AO-50-C1 tube amp retrofit. I understand you're busy, but would you be interested in converting it into a guitar amp? I will of course pay you for your time and parts, and you could use the situation as a video of course. Let me know.
The guitarlogist has some videos on the Hammond conversions, ck him out.
@@jerrystephenson1172 Thanks!
Terry, this has probably already been covered, but what is your day job?
Hello, I work aerospace electronics. Spent 20 years in automotive electronics, 12 years USAF before that. Always had the D-lab shop for extra income.
@@d-labelectronics Thanks for the reply, I know your busy. I'm an electrician by trade/ electronics on the side ( I'm not on your level, I've only repaired 4 amps in my day.) Was a ham, ( ex KA0IVW) life got too busy, too expensive, I let it lapse? I still play guitar around the campfire on occasion. Used to repair CBs years ago, I've had several of those good old Johnson's through my fingers over the years, I toured the factory back in the 70s. It's the first place I'd ever seen puddle soldering, were they pass the circuit board over the pool of solder, neat stuff, take care.
What City are you in??
I have a brand new Black Face deluxe reverb, only one problem is : When I play A. there has some noise, Anyone knows what's going on? I have no idea. Help me!!!!!!!!Please!!!!! I come from China.
what size is that Ungar? Thanks.
It looks like a 776 handle with one of the big 50-60 watt tips. I think he said it hits 900 degrees Fahrenheit. Maybe like a #4036 tip.
Thanks!
2:55-4:02 asmr
Lost in space sound
You could learn two or three chords, learn how to tune the guitar, and then you would have all the tools needed to really hear the amps that you fix. I encourage you; it could be fun!
electrical tape, my buddy, like you hates "it"-hee Hee
Way too fast on the trem Terry. But by now you know that and have paralleled a disc in the trem circuit.
Slowing down the trem is easy. Those three ceramic disc caps,,, just double the value of the one close to the front and bob's yer uncle. As for playing guitar,,, just get one of your buddies to teach you an open e tuning. ,,, fanny's yer auntie.
Tremolo too fast get rid of those ceramic disc capacitors
Cory Williams : That won’t change the speed.
What you do is change some of the three disk capacitors. “Two are .01uF and the other is .02uF. Replace the two .01uF caps with .02uF 400v (or higher voltage) to slow the tremolo. Many people like to use Orange Drop caps in the tremolo oscillator.”
You can also get rid of term ticking by soldering a 0.02. uF cap across the “trem roach” leads.
I learned all this and more from Rob Robinette (search his name + Silverface mods).
Here’s where you find schematics AND chassis layouts for all old Fender amps:
www.thevintagesound.com/ffg/schematics.html
For the love of God and country please tell me you got to the bottom the TAPE!!!!!!
Yes, the ground runner was soldered direct. The other tape piece was on a unused transformer winding
D-lab Electronics love the videos!!!
Friend thank for you help...I would like to have your e mail ...for advice..please
You should really learn at least one chord on guitar!