troubleshooting my PT-80 delay

[jbm222]

I built a pt-80 and it doesn't work.  First, I'll tell you what it does.  The clean signal seems to be coming through fine, but all i'm getting on the delay signal is noise.  I know the delay chip is at least delaying, because I get beats in the noise that change speed when I change the delay time pot.

I didn't use the GGG layout because i did it on perfboard, so i just made my own layout, following the schematic.

I did a few things differently, but not much.

I used a charge pump instead of a 24v adapter

I used a 2n3904 instead of a 2n5088 for the buffer on the post-delay filter.  

I ommited the .1uF cap on pin 1 of the delay chip (figured it was useless in // with a 100uF).  

On the output mixer/buffer opamp, I switched the location of the the 1k resistor and the .015uF cap such that the 1k goes to the inv. in and the .015uF goes to ground... switching the order of series impedances shouldn't do anything, right??

I used // 47pF caps for the two 100pFs coming off the compandor chip.

None of my 1uF coupling caps are electrolytic... i'm using some things labeled 1.0M that look like film caps (i picked up a ton of them for $0.05/pc at a surplus store....they seem to work fine in anything else).

I didn't try to seperate my ground connections (digital, analog, and power supply) because honestly i don't understand how this is possible.

Oh, and I used 1.2K instead of 1K resistors for my voltage divider because I was running low on 1k's.

As far as i can tell, that's all that's different from the schematic.  Would any of those things cause a problem?

Oh, and I'm using the phillips SA571N compandor from smallbear.  And for my indicator FET, I'm using a J201 with a regular LED... right now it's acting funny, but this shouldn't cause the to stop working right.

[KORGULL]

I didn't try to seperate my ground connections (digital, analog, and power supply) because honestly i don't understand how this is possible.

I think I remember having a problem when I first breadboarded a PT-80 and didn't have the grounds hooked up properly.
Read this thread to help you better understand what to do:
http://www.diystompboxes.com/sboxforum/viewtopic.php?t=29982&highlight=digital+ground