New D-lab series Basic Training Tube amp repair How to really fix a dirty pot Not what you think

Sdílet
Vložit
  • čas přidán 19. 08. 2024

Komentáře • 243

  • @GlennJimenez
    @GlennJimenez Před 25 dny

    I wouldn’t be surprised if this guy had the skills to build his own amp.

  • @stevedanby8042
    @stevedanby8042 Před 2 lety +15

    Now this is a great idea and doing it in this manner will be invaluable to so many people who just want to learn and have an interest in this. Forums are great but seeing and watching makes all the difference. I'll be tuning in

  • @joepulltab6355
    @joepulltab6355 Před 2 lety +15

    Awesome!! As someone new to electronics and building amplifiers, this series will be very helpful. Thanks Terry!

  • @dhpbear2
    @dhpbear2 Před 2 lety +8

    Congrats on the new series, Terry! xraytonyb is doing a similar series on his channel. Building an integrated stereo tube amp kit and walking though EVERY aspect of it.
    Tony even tossed the circus board in favor of point-to-point wiring! The circuit is SO simple, it's comical seeing it laid out on a PC board!

    • @zulumax1
      @zulumax1 Před 2 lety +2

      David Perkins, I love Terry and Tony, both great teachers of how to do point to point wiring, and do it right. It is an art, and takes that old school knowledge which is becoming a lost art. I tip my hat to a couple of great teachers here on the tube.

  • @BCEpedals
    @BCEpedals Před 2 lety +8

    This is wonderful to know! This going to be a great series! Excited for more!

  • @kmackiss
    @kmackiss Před 2 lety +7

    Thank you Terry , for this new series of video's . The testing with is what I am always looking for . Please keep releasing your great video's .

  • @tomasjones3755
    @tomasjones3755 Před 2 lety +7

    Appreciate this series; looking forward, to more!

  • @haroldsparkman6008
    @haroldsparkman6008 Před 2 lety +6

    Thanks Terry. Looking forward to learning from an excellent Technician!

  • @jonathanhorne6503
    @jonathanhorne6503 Před 2 lety +1

    Topic suggestion. Troubleshoot a conductive board.

  • @zulumax1
    @zulumax1 Před 2 lety +1

    When I heard the sound I knew what it was, DC across the pot. Once you have heard that sound you know. Then you need to track down the source of the DC and how it is getting there. I had a stepped type treble and bass controls on a Magnavox console that would pop with every step change due to leaking caps. Replaced the coupling electrolytic caps in the preamp and amp and no more pops.

  • @joeteejoetee
    @joeteejoetee Před rokem +1

    I love the look of "Orange-Drop" Capacitors!

    • @GlennJimenez
      @GlennJimenez Před 25 dny +1

      Definitely prettier than those crappy green chiclets

  • @LitesLAB
    @LitesLAB Před 2 lety +9

    Great video Terry, the troubleshooting was presented very well and easy to follow. You rock!

  • @schmaler68
    @schmaler68 Před 5 měsíci +1

    I think I should urgently replace my capacitors on the Orange OR120. That's probably where my problems are. Many thanks, and best regards from Germany, Kay

  • @ScottyBrockway
    @ScottyBrockway Před 2 lety +1

    There can be leakage on the board itself too, and changing the caps is just a temp fix and they aren't really leaky. Should desolder one end first and check if there is any voltage to confirm suspicions. If there is none, start measuring the board, they attract crap from smokers and moisture, also that wax that CBS started adding later can become conductive and it needs to be removed in some cases.

  • @simonspeaker
    @simonspeaker Před 2 lety +2

    WOW! Could be awesome if you could start explain from the very basics and schematics 😮

  • @umajunkcollector
    @umajunkcollector Před 2 lety +1

    WTG Terry, thanks again for sharing your valuable knoeledge. Those dang leaky caps strikes again! Knowing which stage or section of the amplifier to troubleshoot comes from understsnding the circuits of each staage, power supply, preamp, amp, or speaker. The preamp cam be devided into sections, tone, fx, or controls and their tubes. I've learned from you a lot aboit tubes and their purposes or multipurposes, how to break down each stage by their tubes, PS, preamp, and PA. One thing that I do first is troubleshoot for bad connections, then old caps. Way back, we tested tubes first at the Rad Shak becsuse the caps and pots were not old yet. Then maybe a blown speaker from abuse? Sometimes we got lucky, and bought a ""Lifetime"" tube or cheapo speaker from Radidio Shak!

    • @umajunkcollector
      @umajunkcollector Před 2 lety +1

      PS: btw, way back, I had a Rad Shak MIJ guitar amplifier that had two twelves as I recall. It had four tubes, I guess, since it had reverb and tremolo. It was either a 6aq5oir 6bq5 amp. Lafayette sold a simular guitar amp that was supposedly a rebadged Univox. It serms that you favor "made in the usa" amps. The MIJ copy cat amps were built cheap, and at best were good for home practice. I'd like to see you do a vid about an old cheapo made in Japan copy cat amp, to see a diagnostic 50+ years later. . Rad Shak amps are quite rare, but you might find a tubie Univox for funage.

  • @zulumax1
    @zulumax1 Před 2 lety +1

    I think what you are doing is a great idea!
    Reminds me of what Marlin Perkins did with Mutual of Omaha's Wild Kingdom show back in the 60's through the 80's. There was a disclaimer at the beginning of the show that all events may be staged, but depict actual animal behavior in the wild. A great learning tool that recreates events which would be hard to come across by chance in the wild and catch on film.

  • @briancassidy6678
    @briancassidy6678 Před 2 lety +6

    Keep 'em coming! Great time and money saving tips are always appreciated.

  • @zundfolge1432
    @zundfolge1432 Před rokem +1

    wow! MY LAPTOPS speakers wouldnt play the rumble but when I hooked up a mega boom to it, I heard the rumble.

  • @Germinalx
    @Germinalx Před 2 lety +1

    Lots of guys on line. I like Terry.

  • @stephenfabiszak6039
    @stephenfabiszak6039 Před 2 lety +2

    I really enjoyed the video. When you verbally reference the schematic diagram, could you show us on the actual schematic if you have one on hand?

  • @chattanoogaguitarworksguit7956

    Great presentation. Well explained and clear tests/ results! Looking forward to the next episode. You could charge for this stuff

  • @ckdesign
    @ckdesign Před 2 lety +1

    nice idea for the series Terry - thanks for all the great content. you mention the problem here being a leaky "tone cap" rather than identifying it as a leaky "coupling cap" feeding the tone stack. thought it might be helpful to point that out since "tone cap" is the standard term referring to a cap between a tone pot and ground responsible for altering tone and using that term to describe these frequency tuned DC-filtering couple caps could be a little confusing for some audience members. cheers.

  • @dhpbear2
    @dhpbear2 Před 2 lety +1

    2:30 - My guess is a leaky coupling cap leaking DC onto the pot. This is one of those SNEAKY not-at-all-obvious problems.

  • @WillemvanLonden
    @WillemvanLonden Před 2 lety +1

    Keep 'm coming, Terry!

  • @edwardmonsariste4050
    @edwardmonsariste4050 Před 2 lety +2

    It’s always such a joy to work on old hand wired boards and chassis mounted sockets and pots.
    Today’s typical tube amps are ugly multiple double sided circuit boards with surface mount components and a rats nests of ribbon cables. You’ve got to have an electron tunneling microscope to see what you’re doing.
    You literally have to rebuild an amp just to change a blown hissing resistor.
    Good look on your new full time work. Always enjoy your videos!

  • @markcunningham6086
    @markcunningham6086 Před 2 lety +1

    Yep....Im with ya Terry. More please.....

  • @bobr8565
    @bobr8565 Před 2 lety +1

    Keep ‘em coming Terry!

  • @theoloutlaw
    @theoloutlaw Před 2 lety +1

    I would not have thought .3 or .8 of a volt would cause that much of an issue on the other side of the Cap.
    Thanks Terry for the 'awakening' of such things.

  • @Wizardofgosz
    @Wizardofgosz Před 2 lety +3

    Good stuff!
    But no Star Trek references!!! 🙂

  • @CC-te5zf
    @CC-te5zf Před 2 lety +2

    Howdy D-Lab! This was a great lesson!

  • @Uuuuuuurrgggggghhhhh
    @Uuuuuuurrgggggghhhhh Před 2 lety +1

    Very good, Terry. I like this new series!

  • @johnsalaman503
    @johnsalaman503 Před 2 lety +1

    I personally enjoy every one of d labs videos..great job terry

  • @cameronstolhand7149
    @cameronstolhand7149 Před 2 lety +1

    Great idea! I'm down to watch the entire series.

  • @mrd5376
    @mrd5376 Před rokem +1

    Terry,Awesome video as always wish you were closer to my home town! Thanks Dan Penticton BC

  • @jerryjohnson3801
    @jerryjohnson3801 Před 2 lety

    thank you, I've been looking for a truly beginners video series on how to troubleshoot power amplifiers

  • @74cannelle
    @74cannelle Před 2 lety +1

    Very good approach, Terry 👍

  • @MrAlFuture
    @MrAlFuture Před 2 lety +1

    In really looking forward to this series. Great idea! Thanks, Terry!

  • @jackleg266
    @jackleg266 Před 2 lety +1

    terry, wonderful! anxiously awaiting next clip.... thanks

  • @davehunt5706
    @davehunt5706 Před 2 lety +1

    Fantastic news Terry
    You are the wizard

  • @vitoleo7197
    @vitoleo7197 Před 2 lety +1

    very nice Terry. 73 from ON6VL in Belgium

  • @robertcox5228
    @robertcox5228 Před 2 lety +1

    Hi
    Love all your videos. Maybe my hearing is not so good, but I could not hear the rumble. I think a seperate mic for the amps speaker would help. Dub in the audio track. Various sounds amps make when sick are important for diagnostics. Looking forward for more Dlab videos.
    Bob

  • @jdmccorful
    @jdmccorful Před 2 lety +1

    Good deal! Looking forward to this series. Thanks!

  • @ralphj4012
    @ralphj4012 Před 2 lety +2

    For future videos perhaps include a method for comparing the bad component with the replacement, say using ESR / LCR meter etc. Many viewers may not have such a meter but it's the diagnosis / confirmation procedure which should be of interest.

  • @patprop74
    @patprop74 Před 2 lety

    Looking forward to all of this series! Excellent Terry

  • @jimhibert
    @jimhibert Před 2 lety +1

    Nice video, Terry. Please keep ‘em coming.

  • @edcataldo7019
    @edcataldo7019 Před 2 lety +1

    Thanks Terry for giving us access to the D-Lab Team!

  • @John-te3zd
    @John-te3zd Před 2 lety +1

    Great video Terry, love the new series

  • @elgringoec
    @elgringoec Před 2 lety +2

    Tell that DC to get off the pot! 🤔😮😂

  • @denniscrofoot9238
    @denniscrofoot9238 Před 2 lety +1

    Great job Terry, I could even understand it.😁

  • @michaeltuckey7
    @michaeltuckey7 Před 2 lety +1

    Great video! Looking forward to the next video in the series!

  • @eugenepohjola258
    @eugenepohjola258 Před 2 lety

    Howdy. Great.
    I had a persistent problem with my DIY amp. The driver stage of one channel sounded awful and the DC levels were nuts. I disconnected the input cap. No change in levels. Then disconnected the stage neg. feedback cap. Still no change. Finally I disconnected the global neg. feedback cap. Voila ! Unmounted the cap showed a resistance of about 800 ohm. Brand new cap and faulty ! After replacing and reconnecting everything the stage worked fine. Since then I have encountered another leaky cap in the bag of 50 items I bought.
    Lesson. Sacrifice the time to resistance check caps before soldering them in. Will save one a lot of headache in the long run.
    Regards.

  • @colinsvid
    @colinsvid Před 2 lety +1

    Good video terry, I’m looking forward to seeing the next one

  • @richardbrobeck2384
    @richardbrobeck2384 Před 2 lety

    Terry Nice video when I was in high school our Electronics teacher had us built this RCA AA5 chassis but he did not tell us he included either wrong value parts or defect parts !

  • @larrpeninger
    @larrpeninger Před 2 lety +1

    I love this! This is information you don't ever get from a repair center.

  • @OIE82
    @OIE82 Před 2 lety

    Great idea Terry. I always look forward to your videos. I don't know if you would want to give away your parts supplier information, but if you do, showing where and how to find good parts would be a good video too. Of course, that may overload and deplete those vendors' supplies!

  • @squidkid2
    @squidkid2 Před 5 měsíci +1

    I've run across this problem but I've never run acrossed it.😁😁

  • @billhart4710
    @billhart4710 Před 2 lety +1

    Thanks! Well spoken, concise - just what I needed to know. 👍👍 ...

  • @zbaby82
    @zbaby82 Před 2 lety +1

    Excellent! Please more videos like this.

  • @bkbinj6320
    @bkbinj6320 Před 2 lety +1

    Thanks for sharing your knowledge Terry.

  • @jmormino5465
    @jmormino5465 Před 2 lety +1

    Love this Format as a series. Thanks.

  • @openup007
    @openup007 Před 2 lety

    Two knobs up… Good job Terry!!!

  • @johnnaighley9252
    @johnnaighley9252 Před 2 lety +1

    Had the same leakage issue even with a new old stock vintage coupling cap in front of a volume pot when building a guitar amp.

  • @sarbog1
    @sarbog1 Před 2 lety +3

    I just finished building a Fender Champ 5C1 and love it! It is basic, just a volume control, five watt practice amp. I plugged in a 12 inch speaker Vintage Classic from Mojotone... sounds great with just enough low end. Next is a cabinet to protect the speaker... my thoughts the Mojotone Tweed Deluxe 1x12 ...

  • @user-ud2eh9ry4m
    @user-ud2eh9ry4m Před 10 měsíci

    just started fixing amps love this and i have seen the resistor thing years ago when i first got into tube amps as a young teen tried to help him but told him you have messed with this thing to much

  • @simonaguilera1688
    @simonaguilera1688 Před 2 lety +1

    Enjoy it very much. More tutorials please. Best regards

  • @entangledwebmanagement5842

    Absolutely helpful. Thanks, Terry.

  • @edwardhannigan6324
    @edwardhannigan6324 Před 2 lety +1

    Wow Terry, great new series...! Can't wait for more info, just love it..Ed..UK..😀

  • @archiepaton9263
    @archiepaton9263 Před 2 lety +1

    Looking forward to this. Great idea.

  • @kenwhelan3003
    @kenwhelan3003 Před 3 měsíci

    A great new series... thumbs up here in WNY..

  • @audiotechlabs4650
    @audiotechlabs4650 Před 2 lety +1

    This video and the next ones are a vital look at how to repair your own amp. Many of us, your loyal subscribers would have known the answer to the 3 choices you presented because you have explained it before. I knew. By the by, I normally watch CZcams videos on the iPad speakers but on this one I used headphones and the opening music was great! I found out what I’ve been missing! Love from spring in the Rocky Mnts. Thanxz

  • @MrTech337
    @MrTech337 Před 2 lety +2

    I'm trying to learn how to work on amps so I find this very interesting and would like to see more. Would have liked to see the capacitors tested on a capacitance meter once removed.

    • @truckertn
      @truckertn Před 2 lety

      i've seen that done in other places..would love to see terry's take on that, unless i've missed d-lab coverage on cap testing before. great work as usual terry. love the new series. 👍

  • @Fotosaurus56
    @Fotosaurus56 Před 2 lety

    I sent my Champ in to have it serviced, the volume pot was noisy and it started popping and making static. It came back with a new rectifier tube and was still noisy at the volume pot. I replaced the pot myself and the popping came back. Grrrr..the original Fender tube was probably still good. I noticed the power tube and rectifier tube were kinda loose. I replaced the tube sockets myself. All is good. I will be watching the videos.

  • @rickcarter6591
    @rickcarter6591 Před 2 lety +1

    Excellent Video. Short and to the point.

  • @xtrchessreal
    @xtrchessreal Před 2 lety +1

    Yeah... Longtime subscriber and I do enjoy seeing these type of issues and the solution. Perhaps slightly more explanation. Okay DC on a pot but why does that make it scratchy? My guess is DC discharge causing tiny sparks, almost microscopic but enough to change the audio signal from flat nothing to a series of point discharges as the pot surface is rotated.
    Oscillations, hum loops, conductive boards, NFB resistor sizes verses the tap on size of NFB added or removed, Hum in general, plate and cathode wires to close to grid, raised heater...why? and How do you make one? Wrong size pot what happens...symptom, Linear when should be audio tapered, X-Cap bias feed circuit, crackle from carbon comp resistor fail, why dual bias circuit could be useful in these times with hard to find tubes. Some ideas. Love the format, induce a problem guess the issue and why the fix is the fix. Great info channel, keep up the great work.🙂

  • @hestheMaster
    @hestheMaster Před 2 lety +1

    So simple ,with just using a voltmeter to find the errant culprit or culprits. After hearing the pot was replaced and had
    the same issue one must go a little deeper to find the problem. Thanks Terry.

  • @dumpedcabledumpedcable116

    Great idea for a series!!!

  • @vuch9208
    @vuch9208 Před 2 lety

    I really didn't hear the rumble before or after the changes. I did enjoy the video!

  • @jamesrobinsonjr.9384
    @jamesrobinsonjr.9384 Před 2 lety +2

    Really looking forward to this series.

  • @jefflangton6033
    @jefflangton6033 Před 2 lety +1

    Thanks Terry Good Stuff...Jolten Jay Aka Jeff 👍

  • @PhoenixGuitars
    @PhoenixGuitars Před 2 lety +1

    Thank you! Really looking forward to this insight and knowledge. Please continue!

  • @czgunner
    @czgunner Před 2 lety +1

    Awesome video. Looking forward to more!

  • @taylorfusion
    @taylorfusion Před 2 lety +1

    We’ll, it’s about time!!!

  • @kimmassey6596
    @kimmassey6596 Před 2 lety +1

    Great job. Please keep ‘‘em coming

  • @montycline9840
    @montycline9840 Před 2 lety +1

    Great ideal Terry keep him coming please, Thank you so much for thinking of us.😁

  • @BurtonBoyz715
    @BurtonBoyz715 Před 2 lety +2

    This is such a fantastic...
    channel.
    Uncle Doug.... and you.
    FANTASTIC IDEA... for a new series.
    Please stay with it...
    Thanks
    FROM THE SEA ISLANDS OF SOUTH CAROLINA.
    CHEERS.
    DEEP IN THE deep deep SOUTH... in the LOW COUNTRY.
    CHEERS...

  • @justgary4342
    @justgary4342 Před 2 lety +1

    Very helpful tip. Thanks Terry!

  • @jakeblues3676
    @jakeblues3676 Před 2 lety +1

    Terry you’re amazing and we so much appreciate the help given HAM Radio

  • @robertbull6895
    @robertbull6895 Před 2 lety +1

    Great video. Keep them coming Terry.

  • @johnenglish8261
    @johnenglish8261 Před 2 lety +1

    In a word YES!!!👍🤔

  • @petercornell2002
    @petercornell2002 Před 2 lety +1

    Great idea, thanks Terry

  • @donaldfilbert4832
    @donaldfilbert4832 Před 2 lety +1

    Excellent series !! I was surprised that a small leakage DC voltage (under 1 volt) could cause that kind of problem !! Thanks for the series !!

  • @paulomeyer3900
    @paulomeyer3900 Před 2 lety +1

    Great idea, Terry. Tks

  • @miguelrichartmellado2834
    @miguelrichartmellado2834 Před 2 lety +1

    Good old school

  • @sarbog1
    @sarbog1 Před 2 lety +1

    Yes, very cool!

  • @pauldow1648
    @pauldow1648 Před rokem +1

    Short.sweet.and to the point.
    Helps me to learn how circuitry is supposed to work...

  • @christophersambuco9414
    @christophersambuco9414 Před 2 lety +1

    I'm always glad to see a new DLab video on my CZcams feed

  • @jeffberwick
    @jeffberwick Před 2 lety +1

    Very clear demonstration! Thanks

  • @analogblues9606
    @analogblues9606 Před 2 lety +1

    I love it! Thanks Terry!

  • @ronmorey3475
    @ronmorey3475 Před 2 lety +1

    Excellent series! Thanks!