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About LuckyK

  1. Power Base 2 repair?

    I've checked all transistors and have found nothing open. Something is leaking into channel two to give me this destortion. I will keep checking and replacing parts till I hit the right one. Got to be getting close. Thanks
  2. Power Base 2 repair?

    Hello Lou, As of last night, I fired up my Oscope to start looking at what is going on. On pin 7 of the U204-b (MC3408) it has a lot of, I call noise/destortion on the Oscope. This is where I'm seeing this unwanted voltage also. It also leads into the Voltage Translator Stage and would look as if this is where this (voltage/noise) is coming from to start with. Pin 14 is showing my audio and seams to be working as it should depending on how I turn the volume control. I will be checking everything as you have outlined. Nothing burned up on the main output board so I believe the problem is where you are pointing me. I will let you know what I find. Thanks for your input and help, Lucky
  3. Power Base 2 repair?

    I have I believe the older PB. I have the schematics of the Crown web site. I think I could draw it blind folded I've gone over it so much. My voltage is A/C on the Multimeter 1.5v but only on channel two. Channel one works great. Nothing is getting hot or burned anywhere else that I can find. I believe one or more of the Darlington power transisters have shorted. I'm going to start pulling and testing them next. Thanks and Happy New Year
  4. Power Base 2 repair?

    Thanks for your help. I will keep looking for the bad part or parts. LK
  5. Anyone with componant electronic experience? I was given this Crown Power Base 2 amp. Of course it was DOA. Having some experience in electronics I opened it and found the LM7815 had no output. Installed a new one and channel (1) now it is working great. Channel two is working with lot less power and when I input audio/music in the channel is has a frying bacon sound added to it. When I check the speaker output it is showing 1.5+ or - volts A/C. The other good channel is clear of this voltage. When I plug the speaker into channel 2 it it also pops due to this voltage. I have installed a different OP-amp in this channel to see if this was the problem (no change). I know I'm getting close. Anyone that can point me to the area that may be causing this problem in channel 2 would be greatly appreciated. It's been a challange to keep up my electronic trouble shooting skills but this problem has got me. Not sure what else to check without total board level replacement. Thanks