INFO NEEDED PC900 [message #20269] |
Fri, 07 March 2014 16:20 |
UB1LID
Messages: 6 Registered: March 2014 Location: NY
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Junior Member |
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Hi All,
If anyone has a photo they can share via email or such of the PC900 it would be greatly appreciated. The areas of concern are the 8 volt reg's and what the devices are that came from the factory. The devices in this unit now are not original or even close. Nor are the drivers. A resistor in the 8 volt reg was solder blobbed on the underside of the board and I would need the correct value for that as well. There is a string of two diodes with one intentionally shorted with a wire for some reason unknown to me. Anyway, I need to get this straightened out so that I can troubleshoot a non-functioning tremolo.
Thanks,
Lid
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Re: INFO NEEDED PC900 [message #20270 is a reply to message #20269] |
Fri, 07 March 2014 17:07 |
chicagobill
Messages: 2005 Registered: April 2003
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Senior Member |
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Welcome to the place. I can't help you with the photo request, but I can tell you to check the technical section of the website where you will find all of the schematics for the K100C-8 posted.
The schematic will list the correct part numbers and values that you are looking for.
There is only one series diode string on that board. It is the power amp bias string. If one of the diodes has been shorted out with a jumper, someone was trying to reduce the idle current of the power amp. This was either because it was overheating or it was done while troubleshooting the power amp.
Again, welcome.
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Re: INFO NEEDED PC900 [message #20274 is a reply to message #20269] |
Sat, 08 March 2014 06:53 |
stevem
Messages: 4772 Registered: June 2004 Location: NY
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Senior Member |
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Hello and welcome also.
No pun intended, but I can not see why you have a problem with reading the scheamtic, as even without my reading glasses I can make out everything on the listings we have here on the site for the pc 900 board.
Could you post a picture of your board and its bad areas?
[Updated on: Sat, 08 March 2014 06:56] Report message to a moderator
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Re: INFO NEEDED PC900 [message #20292 is a reply to message #20269] |
Sun, 09 March 2014 07:26 |
stevem
Messages: 4772 Registered: June 2004 Location: NY
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Senior Member |
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Q904 is a 38736
Q905 is a 38737
913 and 914 2n3638
Q915 36892 or like a posted a 2n3055 that can be at radio shack if need be.
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