Sound Skulptor forums

Build help and troubleshooting => CP554 Diode bridge compressor => Topic started by: John on September 25, 2023, 09:55:30 AM

Title: CP554 Setup step 6 and 7
Post by: John on September 25, 2023, 09:55:30 AM

My second module is not going quite so great. 

On the initial test I had soldered TR2 and TR1 in the wrong positions which I have now rectified.  

On the second test step 6- the output gain does not increase on the meter when turning up the make-up gain, and TR1 (Step 7) does not effect the VAC value when adjusted. It stays at 0.0002 VAC once the compressor is engaged.

Do you think it could be TR1 and TR2 are damaged and need replacing? or is there something else I should be looking at as well? 

Title: Re: CP554 Setup step 6 and 7
Post by: JPK on September 25, 2023, 04:29:52 PM

Were you able to adjust the bias in step 5?
Check if you can measure a signal on TP1, against 0V, with your DMM on AC volts. It should increase with the gain makeup.
Same thing on TP2.

Title: Re: CP554 Setup step 6 and 7
Post by: John on September 27, 2023, 09:10:19 AM

I've found the issue, I have made the fatal error of soldering T1 and T2 in the wrong positions. I have ruined the transformers trying to remove them and so will have to purchase some more. Probably cheaper to do that in the u.k. I'll fit them and re-test. 
If I have any further issues I will report back. Thanks.