Search results

Search Forums New Posts
  1. Tha fios agaibh

    Frankenstein's Components.

    He's only tacking those rings on the pipe which only takes about 2 seconds of sparks flying. For eye protection he probably just closes his eyes just before striking an arc, then opens after hes done. I wouldn't want to be around that thing when it starts to rain.
  2. Tha fios agaibh

    Seeking help with 12v dc motor controller on golf buggy

    Only way to know what it is for sure is to search for the part number. With flat side of metal tab lying down flat, 1 is on left and 3 on right. Usually 1 is gate, 2 collector, 3 emitter. For a mosfet 1 gate, 2drain, 3 source. Read data sheet to be certain. Your readings look like a shorted...
  3. Tha fios agaibh

    Diode Questions- Attempt at Vintage Turntable Resurrection

    Don't you mean 1S2473?
  4. Tha fios agaibh

    Audio Marantz PM500

    Ahh, the input to Qf01 and 2 were essentialy untethered causing runaway gain. Thank you, I now have closure.:) Happy listening.
  5. Tha fios agaibh

    Audio Marantz PM500

    That's great, good job! I'm curious which exact wires had a bad connection? Jf01, Jf02 inputs? Success is sweet isn't it.
  6. Tha fios agaibh

    Audio Marantz PM500

    Caps around Qf01 and Qf02. Electrolytics for sure, but it's possible others are bad too. You've swapped components in this area from Qf01 side to Qf02 side and the problem didn't move to the opposite channel, so its possibile that a bad cap moved over but still caused an imbalance. I wish I...
  7. Tha fios agaibh

    Audio Marantz PM500

    I think this is a mistake on the print. Jf01 should be connected to Jh02 not grounded Jh05
  8. Tha fios agaibh

    Audio Marantz PM500

    I doubt there's any dc comming out of the amp because everything works perfectly when the equalizer defeat button is pressed, which bypasses the Pf00 equalizer board.
  9. Tha fios agaibh

    Audio Marantz PM500

    To be clear, your unplugging the input source (such as rca output of a cd player) and keeping both speakers connected, right? Sounds like problem is definitely on the left channel, its just that with left source disconnected, you only hear the hiss instead of overly loud. I think there's...
  10. Tha fios agaibh

    Audio Marantz PM500

    Your circuitry must be a revision of the maual but it shouldn't differ much. ? I can't see a reason that removing cf31,2 would cause any problems. It should just prevent current to the base of Qf03,5 so it doesn't switch on. I'm a bit baffled about left/right and how the ballance works into...
  11. Tha fios agaibh

    Audio Marantz PM500

    Don't change values, it will screw something up probably cause irrevocable damage. Only pull caps comming from common arrow of pots
  12. Tha fios agaibh

    Audio Marantz PM500

    The more I think about it I believe thats what's happening. If a bad Cf31 is swapped with Cf32 it will sill have a problem. Try just pulling out Cf31 and try it. Then, put it back in and try Cf32. This shouldn't hurt anything and should isolate which side is giving trouble.
  13. Tha fios agaibh

    Audio Marantz PM500

    Do you have a capacitance /esr meter to actually check the caps? You can't always get away with swapping parts if circuitry is interrelated. For instance if Cf03 was bad and I swapped it with Cf04 the problem would still be there, but just originating from the opposite channel.
  14. Tha fios agaibh

    Audio Marantz PM500

    Your welcome. I'm no expert but willing ti heplp if I can. I'm a big fan of vintage audio. As a kid I had a Sansui receiver. Now I've got McIntosh. My ears can no longer tell the difference between the quality old equipment and the new garbage built these days, but I'll stick with my old...
  15. Tha fios agaibh

    Audio Marantz PM500

    We know you've got a good signal comming in on Jf01,2. Here's my understanding of the circuit. This J01,2 feeds the + input of the opamps then its output feeds the right side of the fader pots. Then the common (arrow) of pot goes to feed different value capacitors (freq selection) and...
  16. Tha fios agaibh

    Audio Marantz PM500

    I don't think the .01 caps are a problem but you can try pulling on lead off and see what happens. I have never seen a ceramic capacitor short without exploding.
  17. Tha fios agaibh

    Audio Marantz PM500

    eytonbranhan, I admire your patience and tenacity. It can be frustrating trying to pin point the problem, especially corresponding on the computer. The video is a big help. The distortion is different than I was thinking. It's sounds more like run-away amplification. Perhaps a transistor...
  18. Tha fios agaibh

    Audio Marantz PM500

    Some are marked, but most are at least that.
  19. Tha fios agaibh

    Audio Marantz PM500

    They're super common tiny things like this.
  20. Tha fios agaibh

    Audio Marantz PM500

    Or .03uf
Top