1

CP4500 Stereo Bus Compressor / Re: Channel 2 stopped working

« on: February 21, 2023, 08:59:21 AM »

Ok. I’m going back home tonight. Tomorrow I’ll do it and report back.

Thanks

2

CP4500 Stereo Bus Compressor / Channel 2 stopped working

« on: February 19, 2023, 07:46:03 PM »

hi. my CP4500 has run fine for a couple of years until last month the 2nd channel stopped working. it mutes when switching the compressor on.

I'll summary the steps I've done:

- I have tried different slots in my 500 chassis (Lindell 6 slots). It does not change anything.
- disassembled the comp and clean with isopropyl every contact I've had access to, including all IC sockets.
- gone through the set up steps. channel A when ok, and in channel B with the unit "in" the output went from 2 V AC to 0.833 V AC with the trimmer all the way in.

gone through the steps in the topic "in case your CP4500 doesnt work as expected":

step 2.1
V+ OK
V- OK
THERE IS NO 12 V IN THE PCB

step 2.2
TP6, 7, 9 = 0 OK. 
THERE IS NO TP8

step 2.3
TP6 1,5 VAC OK
TP7 1,707 VAC NOT OK
TP9 0,06 VAC OK
TP10 0,008 VAC FOR INFO
U16 PIN1 0 VDC OK

step 2.4
TP6 1,497 VAC OK
TP7 12,6 VAC NOT OK
TP9 0,058 VAC NOT OK
TP10 0,008 VAC FOR INFO
U16 PIN1 -0,13 VDC NOT OK

any clue?

Thanks,

Jose