Recent content by OscarEmmy

  1. OscarEmmy

    FM signal distortion mystery - I am stumped!

    Yes, one of the zener diodes has failed - D362. Of course, that might have gone when I shorted the associated transistor. The other diode (D363) is fine.
  2. OscarEmmy

    FM signal distortion mystery - I am stumped!

    Thanks for the tip regarding the probes...I'll do that when the new transistors arrive. Did you mean "test the capacitors and the zener diode connected to the base"? I can see the diodes and there are caps connected to the base, but no other transistors in that part of the circuit that I can see.
  3. OscarEmmy

    FM signal distortion mystery - I am stumped!

    Great...so I was trying to measure voltage at a transistor on the power supply board (Q351 one of a pair associated with voltage regulator) that are attached to a heat sink), and my probe slipped and shorted out the transistor - flash and a puff of smoke, and now of course no sound at all...
  4. OscarEmmy

    FM signal distortion mystery - I am stumped!

    Thanks Dr. Audio - I will do that! I also note this only occurs when the units warms up - from a cold start it plays perfectly at any output level. That would also suggest movement with heat expansion, so a bad solder joint might well be the issue! :)
  5. OscarEmmy

    FM signal distortion mystery - I am stumped!

    Jon, it does not occur at all when using headphones only. When listening to both speakers and headphones, it occurs and can be heard both via headphones and speakers. So it appears related to something affecting the FM signal itself. I say this because AM is unaffected regardless of listening...
  6. OscarEmmy

    FM signal distortion mystery - I am stumped!

    I have a problem with an LXI (Sanyo) 562 receiver (75w per channel) that only affects FM. 1) It works flawlessly on AM, Phono, AUX at any listening level up to full volume. 2) On FM and FM MPX it only works well up to about a 1/4 turn of the control. Beyond this level, loud distortion...
  7. OscarEmmy

    Yamaha K-1020 looking for suggestions on assist motor issue

    I will try all of those and report the results - many thanks!
  8. OscarEmmy

    Yamaha K-1020 looking for suggestions on assist motor issue

    When playing a tape, mainly it plays perfectly, but intermittently the assist motor kicks in a few times and there is a transient gap in the music. It seems to get worse toward the end of the tape, which makes me wonder if it's not a back tension issue? I have the service manual on pdf, and it...
  9. OscarEmmy

    SONY PS-X6 Tonearm Rewire Advice?

    Just bought a nice PS-X6 off Craigslist. The seller told me he could get no sound from it. After a little disassembly of the unit I find that the tonearm wires have been severed (pulled) from the base of the arm - so a rewire is necessary. The TT works well other than that, and is great...
  10. OscarEmmy

    QRX-7500 No Sound (moved thread)

    Thanks. I read EW's post and also watched a video of how to do this. I will record the readings and post the results here in a few days (in the middle of selling our home, so am under orders not to be constantly working on gear in our kitchen)!
  11. OscarEmmy

    QRX-7500 No Sound (moved thread)

    Do I just remove and test the transistors on the top board (the one with the missing fuses)?
  12. OscarEmmy

    QRX-7500 No Sound (moved thread)

    Voltage selector was set at 100V Have tested all 8 out of circuit and readings range from 0.04 to 0.09
  13. OscarEmmy

    QRX-7500 No Sound (moved thread)

    How do I test the transistors in this case?
  14. OscarEmmy

    QRX-7500 No Sound (moved thread)

    Such as a bad resistor?
  15. OscarEmmy

    QRX-7500 No Sound (moved thread)

    When Livin4 said that the top fuse readings F03 and F04 were bad, is that taking into account the fact that I was only taking a reading at one side of the fuse connector (because those two fuses have been removed, side the downstream reading is zero, as no AC power is getting there, of course)...
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