|24th September 2004, 12:52 PM||#31|
Join Date: Apr 2002
Location: Göteborg, Sweden
Blog Entries: 4
Do you have plus 14 volts at pin 8 and -14 volts at pin 4 of the opams?
Do you have DC out at the outputs of each opamp of max 3-5 mV? Do you have almost 0 mV at pin, 2, 3, 5, 6?
Is C5 really 1 uF and nothing else? Is R9 really 100 k?
I think a picture will clear up your placement of parts.
If you have 1% metal film with red and brown at the end, you haven't got that wrong?
Only 12 kohms can't be read wrong!
You haven't missed red, brown and orange which can be very near in colour?
/Per-Anders (my first name) or P-A as my friends call me
PA03 LM4780 amplifier group buy, SIGN UP HERE 80 boards ordered (80 paid) 0 board left.
|24th September 2004, 01:20 PM||#32|
Join Date: Jul 2001
Location: The Netherlands
Maybe even better, post a schematic with the Vdc values you measure and were the signal (AC) is lost.. I'm sure Rod won't mind... to debug it this way..
|24th September 2004, 03:14 PM||#33|
Join Date: Mar 2002
Location: Athens Greece
Guys I found the problem. I disconnected the ground connections at the riaa output going to the preamp and everything is working ok. I will try to find out why this is happening.
Thank you all for your replies.
Very soon I will post pictures of all my project:
SCANSPEAK REFERENCE MONITOR
Best regards to all
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