[sdiy] Nice Noise Source

[Charles Bisaillon]

>> 
>> Can you build it with a CV input for the tuning frequency?
>> 
>> Then you'd be able to sweep through the stations under CV control. Or
>> set your sequencer up to play Stockhausen, I suppose...

> Don Buchla demonstrated a CV control FM radio to David Tudor and John
> Cage in the early 60's:
> 
> "Cage and Tudor visited me at my studio in Berkeley. ...My studio at
> that time was ten feet wide and I worked out on the sidewalk.  It was so
> crowded in there we hauled the workbench out on the sidewalk on good
> days and set up my oscilloscope and worked out there.  Cage came by and
> for voltage control I had hooked up my keyboard to an FM module that I'd
> built, a little module that was an FM receiver and I could play stations
> on it because I had one of the first varactor tuned FMs.  Cage, as you
> can imagine was, just enormously interested in the fact that I could
> tune each key to a station and then proceeded to play the radio."
> 
> This is from the Vasulka Archive.
> 
> -Dave
> 


All of your ideas are great! I finally got the radio to work yesterday by
rolling up a piece of wire on a pen. It really is amazing how this stuff
works, I can change stations by turning the knob or by playing with my coil.
The piece of rolled up wire is so sensitive to capacitance to other circuit
elements that I can sweep through a dozen stations just by moving the coil
slightly. It seems like the more turns the coil have, the wider the FM band
I can receive. From what I've heard with the last coil I've used, I assume I
can go from 90Mhz up to 130Mhz or something similar. To describe it in 1
words: AMAZING.

CV input is going to be a joke, I don't even think I'll need an op amp. The
radio tuning is already voltage controlled with a 10V - 0V range. I just add
another in parallel. I really like the idea of having a different station
for every key!

I'll post the schematic very soon.

Cheers

Charles