8 Jan
2009
8 Jan
'09
8:54 a.m.
Roy J. Tellason wrote:
"One of the celebrated things Widlar did was to
put a "hassler" in his
office.2 When a person came in to his office and spoke loudly, this circuit
would detect the audio, convert the audio to a very high audio frequency, and
play back this converted sound.
[snip]
I *want* one of these...!
It was published in Electronic Design magazine:
"What's All This Hassler Stuff, Anyhow?" (Pease Porridge)
Pease, Bob
Electronic Design, May 15, 1995
I've got a (signed!) copy of the article here. Five op-amps (1x LMC6484, LM837
or similar + 1x LM301A), two transistors (jellybeans), a handful of Rs and Cs,
half a dozen 1N914 diodes, a tweeter (Radioshack 40-1383 or similar -- 2x6"
piezo horn tweeter) and a microphone (Radioshack 270-090 or similar --
basically a cheap PCB-mount electret element).
--
Phil.
classiccmp at philpem.me.uk
http://www.philpem.me.uk/