Ampeg 3158 Combo Vactrol part search.

[Jack W.]

Anyone have a source for new replacement Vactrol optocouplers in the USA?
I have an Ampeg B3 (B3158) with a blown Vactrol VTL5C7.
I see Xvive has new product but none of thier US distributors listed didn't carry and didn't seem interested in special orderings.
I see some on Ebay but have been burned before on conterfit parts. So a bit gun shy there.
This amp is ready to go except for this one part.
Any help is appreciated. Thanks.

[galaxiex]

Small Bear has a "work alike"...

http://www.smallbear-electronics.myb...work-alikes-1/

[J M Fahey]

If unavailable make your own.

A 5mm high efficiency diffused Red Led + a 5 mm CDS cell + 1 inch of 1/4" heatshrink tube + a BIC lighter.

I use nothing else and works like a charm.

If needed can post a couple pictures.

[Jack W.]

Hey thanks guys. Small Bear...totally forgot to check back with them. Last year they had nothing close to the 5C7 specs. The Silonex NSL-32SR3 might work...

Mr Fahey, who's your source for the CDS cells, any particular manufacture, series or part number?
I'm pretty handy with a BIC lighter

[J M Fahey]

I´m in Argentina so my supplier won´t do, but in any case the ones I use are as generic as can be .
There must be some brand and model printed on the original box but in any case counter guys know them only as "5mm LDR/CDS cells , typically used in Colour TVs as automatic brightness controls"
Typically the cheapest ones, these are not Lab measuring class but , as the name says, "resistors which vary in response to light intensity"
All go from at least 1M in the dark (and probably 10M or more) to, say, 100 ohms under light, which is fine.

These should be fine, and as you see there´s not much data available, as generic as can be and obviously Adafruit just sells them.

https://www.mouser.com/ProductDetail...wF5UAWXfZy1B4=



Mine on first sight look exactly the same and probably are.

I trust these way more than any cheap VTL knockoff.

I use them in Compressor/Limiters, AutoWah, optical volume controls, Hendrixy Phasers, alarms, Photo Lab exposure meters, Soldano type channel switching, the works, never the slightest problem.

[Jack W.]

Ah beautiful...nothing helps & saves time like a known workable fix.
Thanks so much Juan, this info will help with a few other ckts around here.
Deeply appreciate it.
Now where's my torch at...