Crate GLX1200H DSP Encoder switch

[Delta362]

I'm working on a Crate GLX1200H that has a broken DSP encoder switch. It appears the amp head took a fall on its face and damaged a few pots and the encoder. I was able to fix the pots as they were just broken solder joints, but not so much for the encoder. When I pulled the control board out, the encoder switch was in two pieces - the shaft/contact wafer, and the base part, with the base still soldered to the board. The small leads in the base part that contact the wafer have been damaged and broken off as well so reassembling the switch isn't a viable option.

I found the schematic and on page 3 it indicates the SW4 part number is 88-607-16. I attempted to send a message to the support at Loud Technologies using their form, but that gave a failed-to-send message notice. I'm having a hell of a time sourcing it. I did also find a Fender 00598300 that appears to be the same part, but it's discontinued.

Any ideas on how to contact someone for the encoder, or what my options may be for a replacement part?

Thanks!

[Jon Snell]

Take a look here.
https://uk.rs-online.com/web/c/?sra=...pdt+dip+switch

Might get a clue from the data.
You are looking for a 4way Single Pole dip switch
Possibly this one; https://uk.rs-online.com/web/p/dip-s...tches/1774289/

[Delta362]

Thanks for the suggestion, Jon! To clarify the part in question, while the schematic calls it a switch (as I also referred to it above in one instance), it's a rotary encoder. Doing a little more research on it, it's an absolute encoder, gray code, 16 position, 4-bit. Looks very much like this.

https://www.partsisparts.net/catalog/fender-pot-encoder

[Jon Snell]

Odd that. Most encoders have only 3 legs.
Take a look here for ideas;
https://uk.rs-online.com/web/c/passi...tary-encoders/

[Delta362]

No luck there when I filter for gray code and 16 position. Also looked at Mouser, Digikey, Newark, and a few other odd places. Next option is to scour for an amp that might use it and see if I can pull it from an assembly.

[Enzo]

Three leg encoders are more common, they are the simple up/down increments we see on panels - incremental encoders. Their outputs are relative - ie you are turning the knob of stepping higher and lower in some parameter. Gray codes and others like it are absolute position encoders. That means the same position of the knob calls up the same output. You don't just spin the knob to scroll up and down, each setting means something. SO for example 90 degree left might be reverb and 45 degrees upper right might mean chorus. (I made up the examples)

Encoders come in sizes and shapes, with numbers of positions, so two that look identical might differ in number of stops say.

That part nimber is an SLM part number, but that was from a different owner and from 20 years ago. The real part number from teh parts list is a Noble SDB161PVB15.

[Delta362]

Thanks for the detailed explanation, Enzo! We'll see if I get lucky and find any.

[Delta362]

I ended up finding a replacement stuffed Crate board on ebay that had the correct encoder. So I pulled the encoder from that board and installed it into the amp. Everything is working correctly now. Thank you!