What kind of IC is this

[Jim Battle]

Philip Pemberton wrote:
> 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).

http://electronicdesign.com/Globals/PlanetEE/Content/3080.html