Bigsby phase shifter??

[Gtr_tech]

Anyone ever heard of/seen one of these? Dated 10/74 on the label, the
name "Kuai" appears as well. Apparently it can be used as a wah/volume
as well.

Pix here:
http://farm3.static.flickr.com/2411/...1ca5c87f_o.jpg
http://farm4.static.flickr.com/3005/...ac07fd5d_o.jpg
http://farm3.static.flickr.com/2378/...888e0fb8_o.jpg


Does any service documentation exist? I have 2 of these in for repair
and both are completely non functional other than noise from one. Its a fairly involved circuit with several transistors, 2 ca3080s, and 3 dual op amps.

[Enzo]

I've seen that twisty pedal assembly before, don't recall where. No help on the docs though.

[Mark Hammer]

Now, the second photo shows a plate underneath with the serial number. It also says "Systems & Technology in Music". I seem to recall that Systech pedals were made in Michigan. Is that the same company?

[David Schwab]

That looks like the Systech logo.... from what I remember. I guess they used to be an electronics repair place or something... they sold the pedal to someone.

That pedal does look familiar.

Here's a Bigsby volume pedal

http://www.guitars.com/features/bigsbyped/MC0011.html

[R.G.]

If you can get clear, detailed high res photos of the top and bottom sides of the PCB and wiring, chances are I can reverse engineer it for you.

Just from the complement of parts, they probably did an OTA phase setup (the two 3080s) and the rest is routing and stuff.

[Mark Hammer]

That was my take on it too. Essentially a marriage of the Small Stone and Phase 45, with more pedal control.