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pcb

  1. J

    SAE Pre Drive Board (SAE 22-0091)

    Greetings all, I am in the process of repairing and restoring an SAE 2500 Pre-Drive Board. In taking out the screws to the hear sink, one of the copper rings separated from the pcb (see !MG_1070). It is the bottom screw hole in the photograph and is the bottom hole of the q4 transistor. In...
  2. S

    Sansui AU-717: Restoration with new boards

    Hey all, after having completed a thorough restoration of my Technics SE-9600, now a restoration of my Sansui AU-717 was in order. I got this amp in working condition, although with a DC offset of ~50mV, a slightly dirty speaker switch and - only detectable with test equipment - a slightly...
  3. J

    PCB's, what's the worst makes for track lift?

    In my experience, some Philips and NAD lift their tracks with the slightest application of a soldering iron, made even more difficult by the way their insertion machines staple the devices to the board so everything is difficult to remove. What's the best and worst you've experienced?
  4. Racingh11

    Soundcraftsmen A5002 driver boards

    I have had a few amps with burned or damaged driver boards, so I decided to make some new ones. I also plan to make output boards to retrofit everything in the MA5002 wire-wrap rats-nest. The first version is basically a remake of the originals, with component and trace placement in the same...
  5. John Tulett

    ReVox B710 MK1 Tape Deck Reproduce Amplifier - A Successful Repair

    Introduction * As documented in report, ReVox B710 Tape Deck – Successful Wow & Flutter Restoration, section "What did this restoration accomplish? While it took almost 2 years to complete this restoration, partly due to my first experience with a tape deck, my breaking the solenoid plunger...
  6. T

    Avante Audio Imperio Pro IMP205

    Hello. I'm looking for someone who has an Avante Audio Imperio Pro IMP205 speaker and can take a photo of the power supply motherboard for me. I am particularly interested in the place marked in the photo. Thank you in advance for your help.
  7. T

    Avante Imperio service manual

    Hello. I am looking for a service manual or a photo of the power supply PCB for the AVANTE IMPERIO loudspeaker. The power supply has failed and I am unable to read the resistance of the two resistors marked in the photo. the resistors are hidden under a layer of silicone used by the...
  8. L

    Rebuilding Crossovers

    I am refurbishing some vintage 2-way speakers (Goodmans Mezzo SL) and I would like to rebuild the crossovers using point to point rather than just recap the existing PCB. I traced the PCB circuit to work out the schematic, but something looks odd to me: it appears the is no filter on the signal...
  9. spctrlhrmny

    replacement parts and substitutions

    Just looking for some general "rules of thumb" ... quite a newbie here. How important is finding replacement components (such as capacitors) that are audio quality? Do you have recommended vendors for finding these? Do you have any preferred places to shop for components in general? (RIP...
  10. ton4eff

    Marantz 2265, 2275, 2250B... P800 Power Supply/Protection PCB Replica

    I decided to recreate this PCB. Most probably they use this one in other Marantz models, that I'm not aware of... In the first place, I made a clean copy of the schematic (with the vintage look preserved, of course ;)): Then, when I was working with the PCB, decided to add an option for...
  11. bitomaxsp

    Marantz 2275 rebuild

    I am rebuilding my 2275. It was in a bit of tired shape i'd say. But when i disassembled it it was more that tired. I guess everyone is aware what is on the picture. I am make 3D model now to 3D print this lamp holder. Once i'll validate that model is ok in reality i'll make it public so...
  12. H

    Leak 2100 - pcb question

    Who likes a puzzle? Have just inherited a beautiful Leak 2100 integrated amplifier. In excellent condition, it appears to function really well. Great, but.. Looking at the pcb I see this (deliberate?) gouge into one of the traces, circled in red mark up. Can anyone tell me what effect this...
  13. Fleime

    Rotel RB-990BX fluctuating bias

    Hello, First off, I am a electrical novice. I guess I know the basic stuff an average person does. I have actually learned most here on AK, but forgive me if I'm not using the correct terminology as of yet. I have a multi-meter. After acquiring some Infinity Kappa 8.1, I was advised on the...
  14. S

    Solder sucker sucked up half of a solder pad

    So, I have a vintage receiver that would occasionally go into protection mode, and I narrowed the issue down to the two voltage regulator transistors in the power supply. They both had cracked solder joints. Strangely, all of their solder pads seemed wiggly and loose, but I got them to stick...
  15. S

    Fixing a broken PCB with jumper wires; will it perform the same as before?

    If you've seen my last post, I accidentally cracked the PCB of my Pioneer SX-50 in a bonehead move. Luckily, only a few traces were damaged, and it looks like an easy fix to me. I'm going to go as slow as I can to ensure I do a proper job on this. However, call me paranoid, but should I worry...
  16. dastinger

    Are these parts compatible?

    Hey guys, I have a Denon 3803 that needs a new PCB. The one that it needs is the 1U-3473-2 (page 46 on the service manual). Now, there's one from a Denon 2803, part number 1U-3486-2 available on eBay (page 41 on the service manual). They use the same chips and look exactly the same on the...
  17. N

    Cad new Yamaha CR-2020 capacitor board

    Hi, My first post here. I have bought a vintage amp (cr-2020) at an auction. I am familiar with electronics but mostly digital electronics. But I have also made five or so recappings of other vintage amps so I do have experience. In the Yamaha it turns out that the e-cap pcb is in very bad...
  18. thorpej

    Best practices for heater traces on a PCB

    I'm working on a line stage pre-amp that I plan to (mostly) build on a PCB. I plan to put two tube sockets on the PCB -- a noval for a 12AX7, half of which will be used for a tone control amplifier for each channel, and an octal for the output stage (a 6AS7 / 6080), again, half of which will be...
  19. P

    Restoring and Cleaning Amplifier Internals

    I've come across a Pioneer SA-510 that was kept in the garage as an amplifier. It started "acting weird" so it was given to me. I respect the vintage tech, and want to bring this thing back to life for normal use in a cared for environment. It's got 2 problems. It is oxidized inside. Rusted on...
  20. Jcamp

    Sansui 9090 Driver Board

    Hello, Have a beautiful 9090 that unfortunately is missing its driver board F-2436. I know I am dreaming but does anyone know where I could find one or contact someone that can get a bare pcb made? 9090 by Jcamp posted Apr 1, 2019 at 6:04 PM Thanks :)
  21. rmunson

    desoldering pcb tips

    Hi folks - I'm preparing to do my first recap and I would appreciate any tips on desoldering the old caps from the pcb boards - I'll be working on an old magnavox solid state receiver. questions: When removing the caps, will I just heat each lead and wiggle it out of the pcb hole? Does it take...
  22. thorpej

    All-Purpose Stereo 5-20 front-end PCB

    In my day job, computer software is my thing, and one thing that really irks me in that discipline is having to do one-offs. Even worse, a one-off that's really similar, but ever so slightly different, to the previous one-off. When that happens, I like to take the time to refactor the code and...
  23. JKBay

    Solderless PCB connection conversion

    Hello everyone. I am new to AudioKarma and though I have some experience I am full of questions and I may, from time to time have some answers to share with like minded people. I thought I would start with a couple questions and hopefully some really great ideas will come my way. Like many of...
  24. Ronito6

    PCB Fabricator - opinion and suggestion request

    Here is the second generation F-2772 phono motherboard for the Sansui X1. Using DipTrace, I sightly modified the trace paths to accept the contemporary small signal relay Omron G5V. Basically I'm hoping someone can suggest a PCB fabricator. A North America based maker is first choice, but...
  25. mattking52

    Question for anyone who has recapped/repaired a Concept 11.0 Receiver

    Hi all, I recently got my hands on a decently clean Concept 11.0 Receiver, and I'm looking to give it a little TLC on the internals. As has been published in this forum and elsewhere, the inside of the receiver chassis is pretty nicely organized, and all of the boards are connectorized and...
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