[sdiy] Additive Synthesis questions

[Ian Fritz]

At 11:33 PM 4/10/2010, Paul Schreiber wrote:
>>Google "Wien Bridge Oscillator" and then Google how Hewlett-Packard was
>>founded (ie what was their first product). Or read the Wikipedia article :)
>
>What sort of incandescent bulb do you use for this? something like the 
>tiny little ones you can get at Radio Shack?
>
>Meh...you use an AGC in the feedback loop.

Jim Williams gives a hillarious account of his attempt to beat the HP lamp 
circuit.  It ended up taking four opamps a vactrol a bunch of diodes 
...  Definitely worth reading to see how a genius designer works.  "Analog 
Circuit Design" Ch. 7 -- Max Wein, Mr Hewlett and a Rainy Sunday Afternoon.

Ian