Recent content by rjsalvi

  1. rjsalvi

    Kenwood KR-9060 (9600) EQ help

    Pre Out & Main In. Why? Because you're not boosting the preamp signal which can increase distortion/noise, or worse, clip the signal before it hits the power amp section. Were it me, the only ancillary gear I'd hook up would be the eq ... and that would be ONLY if your speakers require an eq for...
  2. rjsalvi

    I need a Diode bridge replacement for my Ka-907

    A better way to save yourself from continuous fireworks would be to build a DBT (dim bulb tester). There may be more than one thread in the Kenwood forum which diagram how to build one and how it's used. As far as the schematic wiring diagram vs actual PCB connections ... the general rule of...
  3. rjsalvi

    I need a Diode bridge replacement for my Ka-907

    That's overkill. A KBPC1004W (10A/400V) might be a better choice. First thing to do is find out why the originals tanked.
  4. rjsalvi

    I need a Diode bridge replacement for my Ka-907

    M4C41 looks like a 300V/4A bridge rectifier. If you do a GOOG search for M4C41, you'll get hits for sale items.
  5. rjsalvi

    Bias circuit on Kenwood ka701 amp

    This will work, but you're going to have to solder a piece of wire extension to the wiper lead. Before you order parts, Deoxit the current trimmers and see if it makes a difference. The originals have a carbon track and over time, there's dirt or wear and tear, causing dead spots or sloppy...
  6. rjsalvi

    Bias circuit on Kenwood ka701 amp

    "Is there something upstream from the resistor that may be causing the problem?" I don't know, I don't have the unit in front of me to measure voltages, or test any components. I'm throwing darts from afar based on issues I'd seen with a KA-801 restoration I'd performed. Regrettably, there is...
  7. rjsalvi

    Bias circuit on Kenwood ka701 amp

    Do you have much of a selection of resistors? If so, nudge the value of R5 & 6 up a bit to say, 39, or 47 and see if it drops the voltage. EDIT: I just noticed this is in the Solid State forum...perhaps the moderators can move this to the Kenwood forum.
  8. rjsalvi

    Bias circuit on Kenwood ka701 amp

    I wouldn't chance leaving it on. Are the trimpots (VR1 & 2) set all the way to one side? ...and do they make a difference as you turn them?
  9. rjsalvi

    Bias circuit on Kenwood ka701 amp

    Okay, with the amp on and warmed up, volume all the way down and nothing hooked up to the speaker terminals or inputs, what do you measure -- in mV -- between CP3/5 & CP4/6? Should be 26mV.
  10. rjsalvi

    ka 5700 shorting left channel outputs when off dbt

    Ok ... what you're referring to as a "preamp" is actually the PHONO stage. It's ONLY purpose is to equalize and boost the signal from a phono cartridge. When you switch from PHONO to AUX or TUNER, the PHONO circuitry is no longer in the signal path. However, a short there can affect the rest of...
  11. rjsalvi

    KA-7100 lacking bass

    They're in the signal path and block DC before your tone control and power amp circuits, and establish your bass corner (cutoff) frequency. Less capacitance, higher frequency cutoff, higher capacitance, lower frequency cutoff. Something else to consider ... the restoration of the 7100 may have...
  12. rjsalvi

    KA-7100 lacking bass

    Check Ci7 & 8 and make sure they're 10uF and not lower. Did the rebuilder pull any switches completely apart to clean them? Kinda wondering whether he did the Subsonic filter switch and has something back asswards. You can also download a 40Hz tone to your phone and pipe it through both the 5600...
  13. rjsalvi

    ka 5700 shorting left channel outputs when off dbt

    What Pete said. Transistor oscillation/thermal runaway can cause your issue. His suggestion for focusing on Q13 & 15 is a good one since both those transistors have Miller caps (22pF) and both affect bias control. It's possible that replacement transistors can cause original transistors to...
  14. rjsalvi

    ka 5700 shorting left channel outputs when off dbt

    According to the service manual/schematic -- which could be wrong -- Q17 & 19 are BCE pinouts and your replacements are ECB. That said, the board silkscreen should denote a correct orientation.
  15. rjsalvi

    (working) KA-7300 DC offset/questions (note: outdated questions)

    For a better understanding of headphone output series resistance, take a gander at these posts from @ecluser (posts #6 & #10).
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