The Amp Repair that Almost Broke Me - Marshall JCM800 Combo

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This is a rare 1986 Marshall 4210 - the 112 Combo version of the 2205 Split Channel Reverb, 50W head - that just would NOT cooperate. It had multiple issues, but the main symptom was that it was eating V3 tubes like Halloween candy and, I would soon discover, had almost ZERO output as well and had issues with the switching. When working properly, these amps have that Judas Priest, early Metallica NWOBHM thrash tone many of us old timers grew up on, but will this be the amp that finally breaks me?
Preamp Schematic: drtube.com/schematics/marshall...
Power Amp Schematic: drtube.com/schematics/marshall...
Although it has the JCM800 badge, the 4210/2205 circuit is less of the JMP pedigree and more of a precursor to the JCM900 series with its diode clipping circuits in the Boost Channel.
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Опубликовано:

5 июн 2017

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Комментарии : 762

@TheGuitologist 7 лет назад

Hey guys...thanks for the overwhelming response to this one. I've gotten a lot of questions regarding what was the final diagnosis because apparently I wasn't clear enough in editing. The switching transistor TR1 was faulty. Replacing that allowed the Boost Channel to come alive. The phase inverter tube, V5, was causing some sort of issue as well, as was shown in the video, so it was replaced. It tested good on my tube tester prior to troubleshooting. I edit out tube testing from most videos because it gets laboriously long - 50 minutes even without showing tube testing is getting longer already than most attention spans. In fact, you've probably already stopped reading this. The V1 tube tested on the weak side of good on my tester, but I left it in because it should have still worked just ok, which it seemed to do because it is also part of the Boost Channel which was working before I replaced that tube. The V2 tube was the one I finally replaced at the end which allowed the Normal Channel to function properly and fully. The tube I was using in that position during the troubleshooting tested good on my tester, but for whatever reason, this amp didn't like it. The fact that it tested good on my old Precision tube tester is what led me to assume it wasn't the tube and explore other options. Also, if you'll notice on the schematic, the switching is tied into the grid of V2, which is how the Normal Channel gets muted during Boost Channel operation. My theory was that switching in the IC might have also been at fault. Anyway, hope that clears thing up for those of you who had questions. Watching the video back, I can see why it was confusing.

@daw162 6 лет назад

>>you've probably already stopped reading this

@adrianshingler9783 5 лет назад

The Guitologist I have only just started watching your channel but I have to say you are a star sir! I am an electrical engineer in the UK and have done a little bit of amp repair and build myself, but ultimately I would like to have a set up similar to yours. You bring wonderful old amps back to life that would otherwise be thrown in the skip so well done you hero! 😊👍. Love the guitar playing by the way. Just one question about your signal probe, as you are at plate voltages I presume you have a dropper resistor in line to protect the input of your test amp? Keep up the good work I am already a big fan!!! Keep on rocking 🎸🤘🤘❤️🎸

@johnabbottphotography 5 лет назад

I believe that every repair comes with a lesson; one of those "I should have tried that!" moments. If you took away that kind of a lesson from this, what would it be? (Would it be to break out the chopsticks early?)

@grahamthorpe4256 5 лет назад

ha ha ha thats funny brad my bad

@joelspaulding5964 5 лет назад

Watched and read to the Omega. The knowledge and focus required to repair such perplexing issues... RE-SPECT!

@FransvandenBergeMuziekschuur 7 лет назад

I love the way you explained the proces. My kid was watching you like a hawk. This will help many many youngsters. As a DAD I want to thank you.

@TheGuitologist 7 лет назад

Awesome! I have over 300 videos like this. Be sure to subscribe.

@liveatvictoria6853 7 лет назад

I agree with what Frans van den Berge said, you have a way with showing on the video, makes me think you'd be a good teacher. Take Care. :)

@FransvandenBergeMuziekschuur 7 лет назад

I did. Thank you.

@officialmetalwill 7 лет назад

I'd rather watch an hour long video of you tinkering with an amp than 99% of the garbage they have on TV these days. :)

@surg71 7 лет назад

In a nutshell.

@rbagel55 7 лет назад

The only thing I watch on TV nowadays is the News, and that is only once in a couple days, fuck the TV

@TheGuitologist 7 лет назад

Yep, TV blows. No history on the History Channel. No music on MTV. Propaganda for "news". No learning on The Learning Channel.

@ellarkay9842 7 лет назад

Hey! George Stephanopoulos everyone!

@johnmonroney8614 7 лет назад

agreed. i threw my television in the toilet

@smacman68 7 лет назад

These videos are like a murder mystery! Who dunnit? Well, it wasn't Professor Capacitor in the main board with a leak...let's try Colonel Transformer in the mains section with a short...lol

@TheGuitologist 7 лет назад

Miss Scarlet Transistor is highly suspicous...as is Col. Mustard Cap's work on the classified fusion bomb.

@smacman68 7 лет назад

lol This one was a doozy. It makes you wonder if you should just replace all the tubes in the beginning just to eliminate those as the culprit. I admire your determination and methods of troubleshooting

@God-CDXX 7 лет назад

The highly suspicious find 12AX7A strikes again

@TheGuitologist 7 лет назад

Then I would not be able to film myself flailing around like an idiot. :P But seriously, those transistors were definitely bad also. And it didn't hurt to change all those caps in the switching circuit.

@bucyruserie1211 7 лет назад

Wait a min... I saw that movie, it was the guitarist from Spinal Tap in the hallway with the Beatles album Revolver! Really, same actor!

@jjiacobucci 6 лет назад

Kudos to you! I recently had my amp go bad and brought it to an amp technician who made it well again. Thank God for folks like you who help make things well when they go bad. Great job!

@richardeaton6119 7 лет назад

The toddler babbling in the background is fantastic.

@TheGuitologist 7 лет назад

She's an absolute nutcase. Takes after her mother. ;)

@mark006868 7 лет назад

lolololololololol

@pwnEdge1 7 лет назад

I thought she was talking about the amp, what were you saying :-)

@taterlysaladman9377 7 лет назад

She is trying to tell you that British folks never understood electricity. Or maybe it was just the humidity. From cars to amps they showed their prowess.

@ronj9448 7 лет назад

Live translation for "pre-school school of rock" class.

@vinceparke5740 4 года назад

I don't understand a lot of what you're doing but I have to watch the whole thing. The suspense, the mystery! Awesome vid.

@bluestudio67 6 лет назад

I owned a combo just like this from 1985 to 1987. Best amp I ever owned. A beast. Wish I had it back.

@EricBlackmonGuitar 6 лет назад

I salute you man! You have an unbelievable degree of patience!

@poot111111 7 лет назад

This was one of you most informative and entertaining videos. Thank you for including all of it! It is nice to see a repair that didn't come easy but worked in the end. Well earned sir!

@electroKrunch 4 года назад

I blew the dust of this vid that I missed back then. Great troubleshooting! I get more confident about tearing into an amp I accidently misinstalled a tube in and it flamed a bit. Thanks Brad, keep 'em coming!!

@GustavCI 5 лет назад

Had a 2203 back in late 80's. In my case the switching IC was fried. One of my first repairs. Thanks for bringing me back in time Brad!

@keithmccormick1272 6 лет назад

EYE TROUBLE I USE CAPS :) . I REPAIRED TVS FOR 30 YEARS AND AM RETIRED NOW . I ENJOY WATCHING YOU AND THOUGHT ABOUT KEEPING MY HAND IN REPAIR DOING EXACTLY WHAT YOUR DOING I.E. WORKING ON TUBE AMPS . I AM OLD ENOUGH THAT I WORKED ON TV'S WITH TUBES IN THEM FOR A FEW YEARS AND RETIRED IN 2005 . BUT WATCHING THIS VIDEO SAYS EXACTLY WHY I DONT LOL - I AM ENJOYING MY RETIREMENT . STILL LIKE TO WATCH YOU TROUBLE SHOOT . GOOD JOB. KEITH

@hrsey71 7 лет назад

i like how you go through every troubleshooting step. it really helps for others doing the same.

@TheGuitologist 7 лет назад

Hopefully it helps someone. I know the clips seem to skip around a bit in this one. That's because it was filmed over several days and some things had to be edited for time, but it's essentially all there.

@bhull302 7 лет назад

As an electronics troubleshooter myself (for a living), I absolutely love your videos. Keep doing what you do :-)

@Dan79istheman 7 лет назад

Oh Brad, man, I think I may have been feeling your pain watching this repair unfold. I can relate to these difficult examples. Well done with the perseverance dude.

@TheGuitologist 7 лет назад

Hey Dan, Good to see ya. Thanks for that. It's funny...it's like some spirit is fucking with you and know exactly where your breaking point is. The moment you get right up to the breaking point, they say "ok, let him fix it now".

@twistedwired 2 года назад

Wow, that was quite a journey. I have one of these amps and after several visits to repair techs I finally gave up on it and bought a new DSL 40. Several years later now, I may open it up again and try a few things, so thanks for the vid!

@albertwoodall9932 6 лет назад

THe problem with this channel is it's so addictive. I've lost about 6 hours today. Apart the educational side, I just love your accent and sense of humour (I'm in the UK and just love southern accents) . Please don't ever think of stop making these videos. Just wonderful.

@J0nny61 6 лет назад

Brilliant playing as well as top class repair work. When I did repairs back in the 70's there were very few circuit diagrams available. Keep doing what you're doing, I love it.

@kylendm 7 лет назад

Dude your videos are incredibly informative to someone like me. Appreciate everything you do and how in depth you are!

@TheGuitologist 7 лет назад

Don't lie, you just want to see me go ape and smash stuff. :P But seriously, thanks for saying that. Much appreciated.

@elmerfuddski1929 6 лет назад

kylendm I

@simonlinser8286 Год назад

It's not everyday you see a nice Marshall out in the shade, in nature. Refreshing.

@Dragonblaster1 6 лет назад

I have had the 4212 (50W 2x12 Master Volume) combo from new in 1984. It's never let me down and I only work a few miles from the Marshall factory on the rare occasions when I need a retube or a refurb. The last job was new corners, new handle, new Tolex, new fret cloth, new feet. She looks lovely, but still sports some battle scars.

@hadleymanmusic 6 лет назад

Alastair Archibald do they cater personally to customers? My jcm900 mk3 was stolen I would like another un abused head.

@JohnIainMcFarlanewaspfactor 6 лет назад

Great vid Brad,you go at those amps like a well focussed laser.Love looking at and hearing the Junior too.I am jealous.Thanks again man.

@dieselsk8 6 лет назад

Each video is a learning, and proof that the Guitologist, is a great luthier! Congratulations on the great job! From Rio de Janeiro, Brazil.

@thewizardmountain 6 лет назад

Love the thrash playing at the end once you finally get this thing working! Sweet.

@eddiegeorge4047 7 лет назад

Dont let it drag you down -awesome video - thanks for your efforts

@JWEmbry-wc7qi 7 лет назад

Hey, a new subscriber here; thanks for taking all the time to video, edit and upload this info...I REALLY enjoy your videos!

@AllenCross 6 лет назад

I know squat about guitars and even less about guitar amplifiers, but you made the process more entertaining & engaging than I would've expected...not least with your brief play-test at close. Thanks for the ride!

@timothyjay2012 7 лет назад

Sounds great dude!!! Love that crunch and midrange!!

@TheGuitologist 7 лет назад

That's the Metal Gods tone, man. Gotta love it.

@scuzz152 6 лет назад

I'm a completely self taught amp tech and I've had a bunch of those "I'm completely at a loss here" jobs. I spent almost a week off and on with a repair of a simple scratchy pots job in a late 60's Univox stencil amp made by Garnet here in Canada. I initially told the customer it would be a quick fix. Oops. There was constant static throughout the whole signal chain caused by one damn 5 cent resistor. I thought it was only me who did so much head scratching. Really enjoy your videos and find them very helpful. Thanks Brad!

@johnbhumphrey 7 лет назад

Damn, I get too into these videos. I was stressed completely out until you figured out the problem like four minutes before the video ended. What drama!

@TheGuitologist 7 лет назад

It can really suck when one has multiple issues. You try your best to eliminate variables but it doesn't always work to plan. I did test the tubes before even starting on this, but edited that out for time. Turns out, the 2205 is really picky when it comes to preamp tubes.

@johnbhumphrey 7 лет назад

Not to be confused as a complaint, I didn't mean for it to sound that way. Great entertainment, that video had lots of drama. Keep'em coming.

@TheGuitologist 7 лет назад

I didn't take it that way.

@hjdorn 4 года назад

@@TheGuitologistFunny how it's always the last thing you look at.

@lauscho 6 лет назад

Finally subscribing to your channel. Love these videos! Feel like I'm learning a bit about amplifiers and electronics just watching these. Obviously not enough to do my own repairs, but at least it's giving me some idea of what issues to look out for in tube amps!

@rukozaba 7 лет назад

You are like The amp detective... love your videos!

@there_is_nothing_here 7 лет назад

The Amp Whisperer

@camberwellcarrot420 6 лет назад

CSI Kentucky...

@jeremyturner2873 7 лет назад

When all else fails, poke it with a stick.

@TheGuitologist 7 лет назад

That has been my motto for more years than I care to admit. Works on women too...so I hear... :P

@donlang7964 7 лет назад

My High School Electronics Instructor's Motto for working on stubborn equipment was: " If at first, you don't succeed... Use a Bigger Sledgehammer!!"

@ChrizRockster 6 лет назад

Sure helps find a valve that's microphonic! lol.

@davidmoritz6972 6 лет назад

You mean the Coarse Adjustment Hammer and the Fine Adjustment Hammer I assume... I used to have a large mallet on my bench which had "Coarse Adjustment" written on it in magic marker.

@Twobarpsi 4 года назад

Or hammer.

@corez2508 4 года назад

These videos are great. I'm learning to do my own guitar and amp work and these videos are really interesting to watch.

@johngeddes7894 6 лет назад

For having no background in electricity except a little DC theory, you sure have whetted my appetite to learn this circuitry and everything with it. Voicing your train of thought sure makes me feel like I’m learning something. Wish I could go to school and start all over again!

@jamesdobrovnik 5 лет назад

Another amazing video. I always wanted to do this kind of stuff but wouldn't know how to get started. I can't wait to watch it again.

@BrionF 7 лет назад

Nice job man, that took alot of patience and knowledge!

@deuliciousmafuka3604 6 лет назад

lil bud learning to talk i love it my new fav channel.

@thelonetwangster 7 лет назад

Remarkable ! Wish you lived in the south of France...I quake with fear when I hand my amps to the local dealership/repair dude... Keep up the good work - with all these tips and ideas I'm picking up maybe I'll be able to pass on the dealer and have a go myself...well maybe not...always a pleasure to watch.

@dykeneuk 7 лет назад

Great video. Loved your thought process and troubleshooting method. Great playing too, love P90's through a Marshall.

@TheJeffcurran 7 лет назад

Congratulations. Nice job on the trace work.

@stevehogan8829 7 лет назад

Yes, love the adorable talking and happy sounds... Great snooping.. Great vid.

@mitchellgoulla2232 4 года назад

Great job bro. Dang you know ur stuff. I liked how thorough you were. I liked the fact that you took your time and went into great detail of what you were doing. im wondering if I have any probs. in the future with my amp if I could send it to you. Thanks Mitch

@thesonicsolution1976 7 лет назад

I have a regular JCM800 combo...Single channel, no reverb. Best amp I've ever owned. Had it for over 20 yrs now. drooped in a Celestion Gold 50 watt speaker.....super nice. Recently had it thoroughly serviced...new caps, tubes, and sockets. Hoping to get another good 20 yrs out it. I think I will too. Solid amp

@4deuce31 5 лет назад

My brain just exploded. I understand everything you're talking about. I have to do similar troubleshooting at work but we don't have to chase it down like this thank god.

@wraitheful 6 лет назад

I was certain it was going to be that IC! Great video - bummer you had to swap all those caps and the two transistors. I think the owner of that amp should know it deserves a robust set of vintage tubes. Well done, man!

@47Wolfgang 5 лет назад

Nice work and playing, Wish i had a tech like you around here!

@2007srv 6 лет назад

I had a 82' jcm800 I clipped the clipping diodes out of circuit , made it into a vintage sounding Marshall. Amp builder Doug Bray told me how to do this and it was awesome . good luck

@warmothgmc 5 лет назад

Watching this makes me glad that the JCM 800 I recently picked up is a much simpler design without all that switching crap, and no reverb (1983 4010 vertical input 50:watt 1x12 combo). It is also loaded with a G12M-65, rather than the 70 in the amp in this video. Mine also has 6550’s rather than EL-34’s. I did spend a bit on a full service to fix some issues (replaced tube sockets, new tubes, and replaced any drifted components). Good as new now.

@randallparker8477 7 лет назад

I studied electronics in votech (high school)... I passed the classes with a C... I knew then at 17, I would never do this work for a living. I became a Main Propulsion (Steam) Engineer in the Navy... the system drawings were just as complicated but the components are a lot larger, and easier to troubleshoot. 20 years was a life's work. LOL I did follow what you were doing and finding but had no clue as to what was needed. GOOD JOB!

@TheGuitologist 7 лет назад

Thanks, Randall. Sounds like the spark may still be there in you.

@johnfrancis-staite7762 4 года назад

Excellent presentation and explanations , probably the best on line , thanks.

@gregmiller7631 7 лет назад

I bought this amp. Awesome that I can see the work that was done. The amp sounds great. I put a Classic Lead 80 in it. Also play it through a 1966b with 2 V30s

@leshreddur 7 лет назад

19 minutes in, I watched a bunch of this guys videos, I know he will get her fixed up and purring just right and he will shredd up a nice storm on it to test her out. This old cat knows his stuff and plays like a pro, don't none of ya all ever doubt him, he is the amp / guitar master! I love this guy's attention to detail and his incredible perception, he's made so many old ratty things sing like a, well a thing that sings really, Really nice...

@raymondheath7668 6 лет назад

I didn't see you put the negative feedback wire back on, but evidently you did. What a journey

@nachom1971 5 лет назад

Please make a video on making a signal tracing jig like the one you use. Great job on the channel and awesome videos! I love your sense of humor.

@dkblanke 5 лет назад

I would like to see this too.

@muleblues71 7 лет назад

I used to have the vertical input 2x12 50w combo. man that thing was a beast and heavy.

@captnsquid8151 7 лет назад

I have always played around with radio and amps. Not so much nowadays. I have been a Bass player since 1965. I enjoy your videos, thank you. Also your guitar playing and also have a Tele .By the By I gave up TV in 1991 .Keep on truck'in

@richard66754 6 лет назад

Thank you for sharing your time and knowledge with us.

@rguitar87 7 лет назад

Man, I hope I can bring you my Rivera R-100 for a tune up one of these days. These are great videos; I commend you for vindicating the "experience" of taking Physics II. Cheers from Cincinnati!

@jlindenberger 7 лет назад

Nice playing there at the end my friend!!

@rb032682 7 лет назад

Nice video. That guitar and amp sound great. Nice playing at the end.

@garysellars8914 7 лет назад

5:49 I was just thinking to myself when i saw the amp flipped "Now that's the penny pinching way of doing it." I just hate to see that too. In a well built amp there's just no need for it and it makes working around the pots a pain in the backside. Just discovered your videos! They are wonderful.

@Meme4funBr 7 лет назад

You are a living legend! You rock on electronics and on the guitar!

@mixolydian2010 6 лет назад

You made it well done, cheers for the video

@michaelmitchell7797 7 лет назад

that amp sounds amazing dude!.... great playing too man!

@bobbyu3824 7 лет назад

I have had a similar problem trying to get a reading on a negative feedback resistor while in circuit. I couldn't figure out why I was getting such a low value. Then I realized that when the probes were on that resistor, you also have a connection back through the output transformer to ground. In this case, you were basically reading the connection through the 100K resistor in parallel with that 4.7k resistor between the 100k and ground.

@charlesshaw9090 7 лет назад

Bobby U absolutely right! DC conditions the 100k is in parallel with the 4k7.

@dethstormpx4 6 лет назад

Hi Brad love your vids! Have u run into the issue of the volume going up and down and sometimes complete failure on the evh 5150 3 amps? . If so whats the fix? thx

@jaydawg7820 4 года назад

After all the investigating and the feeling of accomplishment .. i always love the 'pay-off jam' at the end ...

@tbader20 7 лет назад

Hey, Brad. Love the channel! Thanks for doing these for us. Anyway, I am curious as to what kind of audio probe you are using.

@TheGuitologist 7 лет назад

It's just a random probe I found in my stash with a 600V .02 cap on the end. Gator clipped to a cable going to the amp in the background.

@These_go_to_eleven_1959 6 лет назад

Original JCM 800 FTW!!! Love those amps!

@J__C__ 4 года назад

Glad I found this channel. This looks like fun! 👍

@JamesWalshBristolKids 7 лет назад

I love learning about amps... I have Valvestate 80 by Marshall. I love it.

@MixedkidFridaysOfficial 6 лет назад

Awesome channel watched a lot of your videos in the last few months

@dicktomasko1553 4 года назад

Back in the 70's when in electronics class first thing we would do is test all the tubes..nice vid..

@lewisarnold100 7 лет назад

Hey Guitologist-Thanks for all the great videos! Could you point me to a source for those black plastic caps that cover the hardware on the top handle? I have not had much luck finding replacements. Thanks!

@TheGuitologist 7 лет назад

I looked again too and couldn't find just the plastic bit. The whole handle is only about $10 though: amzn.to/2s0LheQ

@alvagoldbook2 6 лет назад

I rewatched this video and I love the signal tracer you used. I recently built an amp that's not getting me any sound, despite that all the voltages check out correctly. My fear is that the output transformer is faulty. I was wondering how you set up your signal tracer so I can narrow things down in the amp. I figure you plug the guitar into the amp you're working on and plug a known working amp in and *somehow* connect test pins to a guitar cable, but I'm not sure how that's done. If you could elaborate on this, I would deeply appreciate it.

@Lex10999 7 лет назад

Great video, as always. Thanks

@axepackermusic8636 7 лет назад

Great job!! its hard to find a good amp tech out here!!

@cattleprods911 7 лет назад

Great video, explaining, and playing.

@lennwoodward4550 7 лет назад

WOW..I did'nt know these type video's were out there...GREAT ... I always wanted to do this for a living...but I can just watch you & the way you explain everything almost makes me think I know what its all about... LOL😎 ..YOU'RE the whip dude... i have a marshal combo...2morro I'll get all #'s & such for you..its not working now..i want you to fix it..how much etc. AND I know that question cant be answered right off😌

@fusion-music 7 лет назад

Ah. The old spring reverb. Thanks for this video Ken. I noticed you said the speaker was 70w and the amp 50w. I heard recently (talking speakers in series or parallel) that the amp had to have twice the output of the speakers. Not only does that not make sense to me, but I always understood the speakers ideally need to have greater capacity than the amp - bearing in mind how they rate amp outouts. Do you have a definative on this? Thanks.

@wheezyjefferson9136 7 лет назад

Cool little amp! Hello from across the river a bit, in Corydon, IN.

@TheGuitologist 7 лет назад

Hi neighbor!

@stevekiley6121 6 лет назад

Just started watching your videos, and am really enjoying them. I wonder where you got all your knowledge and expertise from. Incidentally, I am from the UK, and seeing the Jim Marshall, Bletchley sign on the back reminded me of my first job after University, as a Teacher of Mathematics in a school. One of my colleagues was had the surname Marshall. I found out he was Jim Marshall's brother! I bet he wished he followed in his brother's footsteps.

@fenderbender909 7 лет назад

Hi, what is the LCD accessory you are using with the variac that shows % voltage and current, etc.?

@VmShpman82 7 лет назад

I was amazed at the chain reaction of other components . Especially when you tapped on them w/ a chop stick. LOL Who would ever think to tap those things w/ a chopstick ? I loved it. I liked the chopstick technique.

@CalitranoN 4 года назад

Do you have a video with rewiring or cutting of the 'Death Cap' from a old 69 or 70 100 watt head?

@5minutetone350 4 года назад

I've got a problem with my peavey valve king. It looks like to me that the preamp tubes are hit plating and the amp changes tone drastically after I replace them. Only after a few days or at often weeks. I would really like to have this amplifier head fixed.

@fredchatham6680 4 года назад

Using that chopstick reminded me when I was a kid I was given a neon transformer. A guy at my church was an engineer with Muzak and he told me how the make a "JACOBS LADDER" thingies like in those old horror movies. He told me what NOT to do and warned me to be careful. I followed his directions and after adjusting the distance of the wires it was working. He told me if I stuck a wooden dowel or something non conductive between the wires, the spark would stop there. Only wooden round thing I had available was a pencil. I received a quick lesson that graphite can be "conductive".

@DAVIDGREGORYKERR 7 лет назад

Does that integrated circuit have anything to do with the voltage sent to the vacuum tubes if so maybe change that chip.

@igetmycalcium 7 лет назад

Hey man. I'm in Louisville too. Need to figure out what shop you work at in case I need some stuff done. I've had some bad luck with repairs around here in the past.

@TheGuitologist 7 лет назад

bradlinzy at gmail

@pomod 7 лет назад

Sweet git at the end. Awesome sounding jr.

@edwhite7475 6 лет назад

this is probably a stupid question but where does the white lead go when you are tracing for signal? i dont understand that part.....what is it attached to?...maybe i missed it

@CIRCLEOFTONE 7 лет назад

Awesome vid. You should grab a few solid state preamp tubes. Great for checking amps to negate bad pre's because they are practically indestructible.

@Albertgutierrez 7 лет назад

I like your videos, very educational!

@hotrodgs 7 лет назад

Any way, I enjoy your videos, I just picked up a Pignose 30 amp cheap and I have replaced the batteries and still won't work , would you care to do a video on that amp ?

@Za7a7aZ 4 года назад

Dear Guitologist, I discovered yur channel some 6 months ago and really love the way you present and troubleshoot your projects. Having some electronics knowledge myself its very educational and already picked up lot of things I could use for my own modest repairs. Not being able to sent you stuff or make a donation which will significantly change your holiday destignation, which I think you deserve and would like to donate... I choose to express my thanks with..Standing in the Middle of the Street Naked Screaming "LONG LIVE THE GUITOLOGIST"! Not that I am trying to imply that you suck at what you do I wnder if you are aware of this other repair dude on RU-vid... Mr Carlsons Lab. He is something else.. I always go by the mantra..two always know more than one person. No matter how perfect I think I am, an other person with less knowledge than myself can always contribute something unknown to me. Anyways, thanks for your time entertaining and educating us..