Search results

  1. Spenser

    Kenwood KT-8005 Hum Buzz

    Thank you for the research on transformer restoration. I will do some looking around for possible transformer rewind sources here in Pittsburgh who might do a shellac job. Friends may know in North Hills Amateur Radio Club and South Hills outfit called Pittsburgh Antique Radio Society. I think...
  2. Spenser

    Kenwood KT-8005 Hum Buzz

    Thanks Warren, Mike. Been running an hour with LED installed for the FM stereo lamp. So far so good. Quiet. At 8.18 mm these hat-shaped guys are exactly the diameter of the original rubber lamp sockets. Edit: LED light spectrum of lamp chosen bears on how well indicator color will match up...
  3. Spenser

    Kenwood KT-8005 Hum Buzz

    Hi Mike.
  4. Spenser

    Kenwood KT-8005 Hum Buzz

    Thank you. I got a LED and a 1.5K resistor I can throw in there tomorrow. See what happens.
  5. Spenser

    Kenwood KT-8005 Hum Buzz

    10.2V is the voltage to ground on the supply side of the lamp, with the lamp removed. Thank you for hanging in there on this. Thank you for instructions in Post 12 on type of LED and size.
  6. Spenser

    Kenwood KT-8005 Hum Buzz

    Sounds good. With the following new information still 4.7K for the LED resistor? You may be able to see -- if you zoom in on the prior, foil side pic -- Rk1 was never installed. I apologize for overlooking this earlier. Now observe prior, top side picture. See the 1,000uF capacitor mounted...
  7. Spenser

    Kenwood KT-8005 Hum Buzz

    OK thank you I see now where that voltage off the collector side of Power Supply Qk1 is 24V and that's near where this FM Stereo lamp taps in? So MPX Qc10 when turned on completes circuit to ground? I don't know whether this would be helpful. It's 6.2V across the leads of the FM Stereo lamp...
  8. Spenser

    Kenwood KT-8005 Hum Buzz

    Hi, Warren, Someone did a very neat re-lamp job on this tuner it looks like. Whether he used the right lamps I do not know. FM stereo beacon and switch position lamps (5) are spec 120mA type (according to service manual). 4.2mm is what's in there now and seems to fit the rubber sockets. Meters...
  9. Spenser

    Kenwood KT-8005 Hum Buzz

    Recapped power supply. Condition unchanged. Worth a try for ruling out plus perhaps improved power source. :) All power supply electrolytic capacitors after removal by the way tested good. 50 yeo Elna. Again just to extent Peak brand tester tested. Ck8 was 3.3uF 50V installed vs. what is...
  10. Spenser

    Kenwood KT-8005 Hum Buzz

    Will go ahead and recap power supply now. Hypothesis. It is possible that failing capacitors in the power supply are allowing, when FM Stereo light is engaged, ripple in the power supply that is impacting the transformer.
  11. Spenser

    Kenwood KT-8005 Hum Buzz

    Outside of the thread, a technician raised two questions. What is the current draw before and after the buzzing begins? I do not know. What is the line voltage there where you live? The line voltage here is 117. Another technician raised two questions that I added back into the opening post...
  12. Spenser

    Kenwood KT-8005 Hum Buzz

    Hi Bob. I apologize for deleting the original thread. I was trying to correct that I'd gummed it up so terribly I'd made it virtually unreadable. I am sorry. Could you please now give a little more :) and help me salvage what my mistake lost for the group? Along with your historical...
  13. Spenser

    Kenwood KT-8005 Hum Buzz

    I will turn this tuner over to a technician -- if feasible -- to repair and align. I'm afraid Occam's Razor this is simply a noisy transformer that does not like the normal current load. I'm counting 31 adjustment points -- nine alone on the all-discrete MPX board. For an alignment-qualified...
  14. Spenser

    Kenwood KT-8005 Hum Buzz

    Power supply voltage at pin 10 is 13.5V where it should be. Same also at the MPX board supply pin 4. Power supply Pins 7 and 6 are a little high. Pin 7 is supposed to be 27V and it’s 27.7 and Pin 6 is supposed to be 24V and it’s 25.6. Power supply Ck5 47uF16V might be in-circuit leaky...
  15. Spenser

    Kenwood KT-8005 Hum Buzz

    If you have an interest in the Kenwood KT-8005, there is a decent copy of schematic and alignment instructions on HiFiEngine. Even better, an excellent digital copy of the service manual, and the owner's manual, can be purchased at this time from Analog Alley. I bought them both. The version...
  16. Spenser

    Kenwood KT-8005 Hum Buzz

    Let me try this again. My first attemp at this thead was incoherent on my part. I apologize to anyone whose original material got deleted and will try and get your input back on here with attribution. Thank you. Edit: was able to recover the following... "The KT-8005 was my first high end...
  17. Spenser

    Things to Watch Sansui AU-517

    You make a good point. I will take a peek. Inspect for corrosive-adhesive. Nice picture. Thank you. Looked over the thread. Extraordinary, of course. The guy's amazing. Thanks again.
  18. Spenser

    Things to Watch Sansui AU-517

    Guess what. When I got it home -- one channel was all-of-a-sudden weak -- moment of panic. Aha! It was THE SWITCH. True story. I'll be taking care of that switch. Thank you for the instructions and commentaries. Boy the guy who the seller got this AU-517 from, he really took care...
  19. Spenser

    Things to Watch Sansui AU-517

    Any experience with volume control and what can be done if at-issue. Not saying this unit has volume control problems. I have not seen it yet. Just putting it out there in case this is something to have on the list for folks. Thanks everyone notes thus far out-of-sight good. Thank you!
  20. Spenser

    Things to Watch Sansui AU-517

    I am looking for advice on things to watch out for on the Sansui AU-517. Anyone have any wisdom to offer? I have zero experience with Sansui integrated amplifiers. The seller is a trusted friend of a trusted friend and has a 15-day return policy. I will probably come home with the amplifier...
  21. Spenser

    Yahama T-1 Overhaul

    For those of you wtih a T-1 or planning on getting one, there's quite an owner's manual. Be sure to check it out. ...I'll ask my brother. He knew students and professors who worked there.
  22. Spenser

    Yamaha CR-400 Static Channel Repair

    Good point on flux. Very cool on flux remover product mention. I've always just used alcohol. This unit is for sure a case where there was definately flux contamination dating back to manufacture. Scratched it away or toothbrush with alcohol as I went.
  23. Spenser

    Yamaha CR-400 Static Channel Repair

    Went ahead and shotgunned most of the resistors in that channel. No soap. Button it up and walked away. Well, after changing out the caps and remaining small transistors in the left channel. Voltages all OK. Might rebuild the power supply. Might take it back to Vince Bomba. See if he can...
  24. Spenser

    Yahama T-1 Overhaul

    OK the tuner is back from Michigan. Punker X sorted out why it was not working right. No small potatoes to figure it out one of the filters was bad and do a replacement hand match. Also the manual is somewhat incomplete and incorrect. He figured that out, too. Did the repairs and aligned...
  25. Spenser

    Yamaha CR-400 Static Channel Repair

    Cleaned the dc offset and bias trim pots. Replaced tantalum capacitors (C602/622). Rechecked resistance measured in-circuit of 36 of the resistors in the power amp circuit again. All good. Replaced resistors that are raised off the board, (R628/630/616/636). Still have the low volume, steady...
Back
Top Bottom