Recent content by jkaley

  1. jkaley

    MX110 hum (continued)

    I did Dave’s 2 resistor circuit by adding two small terminal strips. It put the voltages right on. Thanks Dave!
  2. jkaley

    McIntosh MC225 transformer buzzing

    My 225's power transformer was buzzing too. I removed the transformer and re-flowed the tar with a hotplate. Temps and such here: https://audiokarma.org/forums/index.php?threads/mc225-mechanical-power-transformer-vibration.1039753/post-16647488
  3. jkaley

    Mc225 mechanical power transformer vibration

    Just a follow up for archive purposes. I reflowed the tar inside the power transformer and it’s dead quiet. Using a hot plate, I started at 250F on each side for 20 mins to warm the tar evenly. Then to 300F with the top facing down for 1 hour. Then gradually raising the the temp to 350F for 1...
  4. jkaley

    Mc225 mechanical power transformer vibration

    Thanks everyone. Don't have a megohmeter, but I'm fortunate to have a spare NOS M-221 power transformer for comparative purposes. Using an ohmmeter, my buzzing PT has the same impedance values as the NOS PT. To wit: Primary 1.2ohms. Secondary B+ 2.7ohms Secondary heaters .4ohms As people have...
  5. jkaley

    Mc225 mechanical power transformer vibration

    I pulled the PT out. No signs of tar leakage. Going to research/experiment with the tar melting point. Start at lower temp and move up from there.
  6. jkaley

    Mc225 mechanical power transformer vibration

    Refugee: Thanks for the info!
  7. jkaley

    Mc225 mechanical power transformer vibration

    True. I just want this one to be dead quiet like my other 225’s.
  8. jkaley

    Mc225 mechanical power transformer vibration

    Thanks! Vibrated with original thermistor and with the replaced CL-80.
  9. jkaley

    Mc225 mechanical power transformer vibration

    Recapped an original Mc225. Before starting the job, I noted the power transformer was buzzing and thought new Authenticap cap cans and electrolytics would solve it. Finished the job and power transformer was still buzzing. Plugged it into a DC blocker to make sure no DC was getting to the...
  10. jkaley

    What did I do to my H.H Scott 222-D tube amplifier?!

    A classic example of "If it ain't broke, fix it until it is!" ;)
  11. jkaley

    What did I do to my H.H Scott 222-D tube amplifier?!

    With all due respect, do you have much soldering experience? My guess is cold solder joints or some of the solder is grounded. Way too much solder too.
  12. jkaley

    Fisher 500b one channel no sound

    Since you’re requesting non-technical ways to trouble shoot it, there are limited things that can be suggested; most of which you’ve done. Pull and clean the reverb jumper pins? It’s been worked on since it has a silicon rectifier bridge, but the coupling caps and electrolytics look original...
  13. jkaley

    Fisher 500b one channel no sound

    Quickly flip all the switches on the front up and down a few times; especially the tape monitor switch.
  14. jkaley

    MX-110Z: A Simple Modification for Reducing Hum

    Nice job narrowing that down!
  15. jkaley

    MX-110Z: A Simple Modification for Reducing Hum

    Never had any Vitamin Q’s, but the K40Y-9 works and fit fine. Any good cap will work here as it’s a low voltage application only there to filter out any DC.
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