[sdiy] vactrol?

[Paul Higgins]

On Saturday, Aug 20, 2005, at 12:32 US/Central, Peter Grenader wrote:

> There's also a Canadian firm making vactrol-type devices (the name 
> escapes
> me right now -duh) which I've heard good things about. I want to say
> Soltronix or something along those lines, but I'm pretty sure that's 
> off the
> mark.

You were close!  The company name is Silonex (not to be confused with 
Siliconix, which I think is now part of Vishay), based in Montreal.  
They're very helpful people--I got a really nice sample package shipped 
to me free for answering a couple questions about my intended 
application.  One caveat--last I checked, their website (for their 
Audiohm optocouplers) listed some parts that have been discontinued.  I 
think all their matched duals are gone.

> Some of these are very fast though (M&K used them as the primary
> ingredient in the limiters within their whiz-bang subwoofer amp which 
> had a
> 1/2 cycle response time at a 125 hertz - that's pretty damn fast for a
> photoresistor.).

Some of them, particularly the NSL-26, have a very fast rise time.  
Other models are similar to the Vactrols.  Info and datasheets here: 
<http://www.silonex.com/audiohm/index.html>

-PRH