Recent content by tabpat

  1. tabpat

    HELP! Diode identification

    I did, but the readings were all over the place. They weren't much different than the left, however. I'm guessing that the meter was being influenced by the actual program material.
  2. tabpat

    HELP! Diode identification

    I would agree, but it started doing this with all stock components and it was never worked on. I have now replaced everything with no luck. I (once again) pulled all of the resistors and found nothing out of spec. So, maybe it's a voltage issue...but I have no idea what the correct voltages...
  3. tabpat

    HELP! Diode identification

    Both amps are getting the same voltage. I've tried so many things...I'm sure I did measure the DC just before it clicks....but I will try it again tonight. I took this receiver on as a favor for a friend. I should have known better...
  4. tabpat

    HELP! Diode identification

    I appreciate the "interrogation," BTW. I feel stupid for not being able to locate this problem. Everything seems to check. Soooo frustrating. It's tough without a theory of operation or schematic. I'm flying blind.
  5. tabpat

    HELP! Diode identification

    Any signal that I pump through it - either via the built-in preamp or using a music player feeding the main amp-in jacks - once the volume gets to a moderate volume on the right channel, the protection kicks in. Any input of any strength on the left input doesn't. So, let's say I chose the AM...
  6. tabpat

    HELP! Diode identification

    Here is the entire board...
  7. tabpat

    HELP! Diode identification

    I test with 8 ohm Goodwill home theater junkers. I keep a pile of them for such an occasion. No, this has one relay that lifts both channels.
  8. tabpat

    HELP! Diode identification

    Basically, I've run out of ideas. All of the diodes have been replaced. All of the transistors and caps as well. The problem stays on the right channel, even if I physically swap the amp boards and outputs. It has to be in the protection circuit. Even with the pre-amp decoupled, it does...
  9. tabpat

    HELP! Diode identification

    Thank you! I'll try that tonight - and I actually have some at home. The drive transistor has been replaced as well with a NOS transistor. If this doesn't work, I'm just going to have to bypass the relay and see if anything pops. This unit is really getting to me! I'm out of ideas...
  10. tabpat

    HELP! Diode identification

    I've been working on this Project One Mark IIIB for weeks now (on and off). Long story short, the protection relay activates on the right channel - mid volume - with or without a load. I have isolated the preamp/amp, swapped amp boards and outputs (left to right), replaced all transistors, all...
  11. tabpat

    Project One Mark III protection mode

    Sorry...I thought I was posting in the Solid State forum. I've reposted it there, so if one of the mods could delete this one...
  12. tabpat

    Project One Mark III protection mode

    I took on a project (pardon the pun) for a friend of mine who is trying to get his brother's old Project One Mark III stereo working again and surprise him with it. He initially told me it was "blown." Honestly, I couldn't find any issues other than really grubby switches and frozen meters...
  13. tabpat

    Project One Mark III protection mode

    I took on a project (pardon the pun) for a friend of mine who is trying to get his brother's old Project One Mark III stereo working again and surprise him with it. He initially told me it was "blown." Honestly, I couldn't find any issues other than really grubby switches and frozen meters...
  14. tabpat

    Lafayette LR-1500T - need help ID'ing these transistors

    Thanks! I did eventually get it all sorted. It's working great, now...
  15. tabpat

    Asymmetrical amplifier output on sine wave - LR-1500TA

    OK, an update (of sorts). I replaced the outputs on that channel and it cleared up *most* of the issue. Now I'm fighting something else, but I thought it was part of the original problem. The right channel is much stronger than the left. I tested voltages and everything was fine. I injected...
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