Recent content by Davron94

  1. Davron94

    HAIR METAL, list your one "guilty pleasure" tune!!

    Great thread dude! Love some80's/ 90's hair-metal! This is my all-time favorite though! Miljenko Matijević has an incredible range and is still hittingit today! I saw them about 3 years ago at the Whisky in LA and it was a fantastic show!
  2. Davron94

    Marantz 4230- Zero bias reading, Need Help!

    Is there anyone out there that has worked on a 4230 and would know where to look to find the root cause of this issue? I've got a dim bulb on the DBT, output from all channels, and the bias varistor diodes check out on the diode test for no reverse bias. I tested all of the outputs and they are...
  3. Davron94

    Marantz 4230- Zero bias reading, Need Help!

    Hi All, Been dealing with a testy 4230 unit for several months now. I have rebuilt both amp boards with new caps, transistors, several resistors and diodes that were suspect, and the outputs. I also rebuilt the PS with new caps, transistors, and diodes. I had the unit up and running fine (biases...
  4. Davron94

    4230 Amp Board Short. Need Help!!

    Hi Dankik, I'm still struggling with this unit. I have it back up and running though with output from all channels. The weird thing is that now the bias settings on both sides of the left channel board are stuck at about zero (right channel board is perfect on both sides with 15mV). Turning the...
  5. Davron94

    The Official SOTA Turntable Thread

    Hi All, The proper drop of the sub-chassis below the plinth should be 1/8" with perfect level reading:
  6. Davron94

    Little things matter - a bit of SOTA freshening

    Very nice! I wish I could switch out my black metal plates for wood. It looks so much better!
  7. Davron94

    Marantz 4230 FM/ AM Issues

    Ok, thanks for the input. I don't see any broken ground wires anywhere, but it does get pretty messy underneath where all the switches are. I was able to get somewhat of a stereo signal from a couple of channels by tweaking a couple of the FM pots on the tuner board, but the stereo signal does...
  8. Davron94

    Marantz 4230 FM/ AM Issues

    I have a restoration project here that I just completed replacement of the transistors, caps, outputs, and a few of the resistors on the P700 boards, and a rebuild of the PS with new caps, transistors and diodes. the PS is at 35v DC, and the amp boards were able to bias properly at 15mV except...
  9. Davron94

    4230 Amp Board Short. Need Help!!

    The issue with the hot left channel P700 board seems to only occur with FM playback at mid to high volume. I rechecked the bias on the outputs and one side will only adjust down to 18mV before it stops. i would not think that 3mV higher would cause the board to get hot to the touch. The AM/ FM...
  10. Davron94

    4230 Amp Board Short. Need Help!!

    Hofferwood and Dankik-Thank you very much for that information!!! I switched out all of the outputs with the Onsemi's and no more firecrackers! That cheap china crap had me chasing ghosts! Everything seems very stable now and all out puts can bias at 15mV. Been burning it in for about 10 hours...
  11. Davron94

    4230 Amp Board Short. Need Help!!

    KSC1845, NPN, ECB was used for H701/ 702/ 703.
  12. Davron94

    4230 Amp Board Short. Need Help!!

    Ah! Ok, great to know! Thanks for that. I will order the Onsemi and see what happens. The strange thing is, is that when I rebuilt both boards, the unit ran fine for several hours. Then I went to fix an issue with right channel noise, found that problem (one of the 3v, .5ohm resistors on the...
  13. Davron94

    4230 Amp Board Short. Need Help!!

    The DC Balance instruction came from the person who sold me the kit off of Ebay. He is a reputable seller of rebuild kits and is well regarded by Admins on a few of the Marantz pages on FB. His procedure is a bypass if you do not have an O-scope. His process is as follows: -Set DMM to DC...
  14. Davron94

    4230 Amp Board Short. Need Help!!

    This is redundant to the next post. I could not delete this.
  15. Davron94

    4230 Amp Board Short. Need Help!!

    The components replaced were all of the caps, transistors, and a few of the resistors when the outputs first started blowing.
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