How to understand the Digitech pds 20/20

[any]

Hey all,

This has been a somewhat overdue post from my side, but some recent events finally triggered me.
I love my PDS 20/20 "Multiplay" Digital delay, I love it to bits and I really want to rehouse it and add
some usefull modifications.

First of all, in 10 years of playing and 5 years of d.i.y. I have never seen a more archaic delay from
a large manufacturer. The kind of sounds this box produces straight from the factory is amazing!
This is due to the clock setup, which is always adjustable (speed, width, time) even in the
"loop" mode. and in every delay range (chorus,flanger,delay).
Anyway before I drift off in how cool all of that is, fact is, I don't know any other delay out there that does the same.

I've downloaded the schematic which is at experimentalistsanonymous.com (colin's site)
but it seems it is only part of the schematic and not the full set.
I can't seem to determine what the input, stereo outs and control functions are there's markings
called a b c d e f g, but I'm not sure what's what.
Things I would like to attempt to implement are:
- an effects loop on the delay path, before the final mixing stage
- upgrade the opamps in the signal path to improve sound quality (found some earlier posts on this)
- Further try to minimize noise and clock bleed
- Add a "delay trails" option, which is probably impossible or quite complicated as the delay input
  on the pds is always on.

If anyone has some "at hand" knowledge that could help me advance in understanding my pds 20/20
I would really appreiciate it!

If anyone want's to glance over the schematic it can be found here: http://experimentalistsanonymous.com/diy/Schematics/Delay%20Echo%20and%20Samplers/Digitech%20PDS2020.jpg

[slacker]

I think you need to find the other page of that schematic, that looks like it's just the actual digital delay part without any of the audio input and output sections. Presumably they are all on page 1 of 2.
I think the audio comes in via A and goes out again via B but that's about all I can figure out.

[any]

See, I was getting that feeling too, not seeing any obvious input buffers/mixing stages...
I've emailed Digitech to kindly send me the full schematic, let's see if my soothing voice will open their heart.. 
If that doesn't work I'll probably trace the pcb and try to reverse engineer it.

[Ssmit]

This thread is relevant to my interests! Except I'm more interested in the power supply part. I seem to have blown something that only affects the power input from the 1/8" jack, as it operates just fine on batteries (or a 9v adapter clip). I just can't figure out where that whole thing comes into play.

[any]

This thread is relevant to my interests! Except I'm more interested in the power supply part. I seem to have blown something that only affects the power input from the 1/8" jack, as it operates just fine on batteries (or a 9v adapter clip). I just can't figure out where that whole thing comes into play.

99% sure it must be the jack assembly as the battery is wired through the jack and thus shares the same connections on the PCB.
I've installed a regular boss 2.1mm barrel and it will fit.

I've send out an email for the full schematic, no idea how they will respond... I've heard both good and bad stuff about similar requests,
let's hope this time they'll make me smile!

[Ssmit]

This thread is relevant to my interests! Except I'm more interested in the power supply part. I seem to have blown something that only affects the power input from the 1/8" jack, as it operates just fine on batteries (or a 9v adapter clip). I just can't figure out where that whole thing comes into play.

99% sure it must be the jack assembly as the battery is wired through the jack and thus shares the same connections on the PCB.
I've installed a regular boss 2.1mm barrel and it will fit.

I'll have to check this out. But I did take it apart awhile back, and there was a blown part (I think it was a capacitor...can't remember)