Sound Skulptor forums

Build help and troubleshooting => CP5176 FET compressor => Topic started by: dmq6 on November 22, 2022, 04:45:43 AM

Title: Pop sound and some smoke upon testing
Post by: dmq6 on November 22, 2022, 04:45:43 AM

I had begun the setup process on my CP5176 and upon plugging the unit into my 500 extension cable, there was a pop and a bit of smoke coming from somewhere around the power transformer. The power button is unresponsive (no green light) and I don't register any voltage when checking the test points as per the instructions.

Hope I did not ruin the whole unit! I think I just need help isolating what could be causing the unit to not turn on or respond, whether it was the pop sound or if I need to just start checking every component from the top. Thank you!

Title: Re: Pop sound and some smoke upon testing
Post by: JPK on November 22, 2022, 07:42:09 AM

Remove the DOA.
Check that R56 and R57 are measuring OK in circuit.
One of them may have burnt. If not conducting anymore, you need to replace one or both.
Then power up again. Turn off quickly the LED's does not light up.

Title: Re: Pop sound and some smoke upon testing
Post by: dmq6 on November 22, 2022, 06:27:32 PM

Thank you! Could I ask, how should I check that R56 and R57 are ok in the circuit? 

I have followed the setup guidelines. When I use my meter to check voltage on V- (black probe to test point 0V) I get 16 volts but on V+ I get .001volts. Also when I test TP7 I get a zero reading.

Title: Re: Pop sound and some smoke upon testing
Post by: JPK on November 23, 2022, 08:34:12 AM

Simply measure the value of the resistor with your DMM in Ohm position without de-soldering the resistor from the PCB.
If it shows a higher value than 5.6 ohms then it is probably dead.