Yes, please put that circuit up.

----- Original Message ----- 
From: "Butch Bussen" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, April 12, 2015 8:21 PM
Subject: light detector


>I thought I kept the message I wanted to respond to, but I didn't.
> Anyhow, I wrote an article in qst way back in July of 1985 called the
> squawker.  It uses a 555 chip a couple resisters and a photo cell and
> almost anything for a speaker.  We actually used an old cassette recorder
> mlicrophone for the housing and the cartridge as the speaker.  I can put
> up the circuit if anyone wants it.  Will run on 5 volts, not sure how high
> the 555 will go, but I ran mine on a 9v battery.  If you put in a closed
> circuit phone jack as I did, it can become a continuity tester.
> Pitch changes with brightness.
> 73
> Butch
> WA0VJR
> Node 3148
> Wallace, ks.