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Questions and Answers
What Are OptoisolatorsFrom aya--(at)--arthlink.net Thu Jul 1 09:49:29 CDT 1999 MF68SF9DSF
micK pages
From: "Gil Ayan"
Newsgroups: alt.guitar.amps,rec.audio.tubes
Subject: Re: LDR's - what are they and where do I buy them?
Date: Wed, 30 Jun 1999 10:32:29 -0700
X-Posted-By:--(at)--38.13.114.187 (urula)
X-Mimeole: Produced By Microsoft MimeOLE V4.72.3155.0
Xref: geraldo.cc.utexas.edu alt.guitar.amps:187172 rec.audio.tubes:127063
Jeff Stapleton wrote in message <7ldhmj$fd1$--(at)--fx2nh3.news.uu.net>...
>Mesa/Boogie uses LDR's (apparently some sort of light triggered switch) in
>many of their circuit designs. What do these thingy's do and where might I
>find them?
Go here:
http://www.egginc.com/Opto-110/vactrols.htm
and read all about the Vactec optoisolaters (used by Fender, Boogie,
Soldano, etc.).
What do they do? They are a photocell which gets triggered by an LED, in
essence achieving silent switching (hence the name, LDR - light dependent
resistor). They cost around $5-6 a piece, and can be ordered from Newark
Electronics, Magic Parts, etc.
Boogie uses both the VTL5C1 and VTL5C4 types, Soldano uses the VTL5C1
exclusively, etc.
Here's a minute-sized picture of the bugger.
Good luck,
Gil
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end
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