PCB Alert: Pitch to Voltage Converter

[Harry Bissell]

    I'm making up some printed circuit boards for a pitch to voltage
converter.
It is a Ramp-Sample Hold design based on the Etherwave Pitch to Voltage
converter designed by Bob Moog. (yes THAT Bob...)

    I've layed out a single sided pcb, 3.5" x 5.5" soldermask and
silkscreen. It uses a MAT-01, -02, LM394, or two trannies of your
choice... and I've included a playpen
area for those who want to hash in a CA3046.
   For those not familiar with this P/V method, it gives an accurate
output every other cycle of the input frequency.

    For Etherwave Theremin owners this PCB has the 8 pin header that you
need to get all power and signals direct from the Theremin. I've
included the Volume Control Voltage mod right on the PCB so all you need
to do is plug in the 8 pin cable. I've modified the Gate control circuit
to make it update faster... it will give a gate output when the input
frequency is >10Hz, AND the Volume CV is > 1/2volt.  It would be easy to
change the minimum frequency to anything you want....

    For Volt/Hz users, this board can convert the frequency of the
oscillator to a linear control voltage suitable for driving Volt/Octave
VCO's. It will take a little time to track low notes because it only
updates every other cycle... for instance a 100Hz input would lag behind
20mS (not glide... just delay...) A 1K would update in 2mS.

    There is NO filters or other signal processing up front of this
board, so I don't think it
would work well with guitar, voice, etc... but then again the
"Tachometer" types don't work either. This is the same P/V method used
in the 360 Systems "Slavedriver" and the P/V works very well. Its the
rest of it that doesn't work...

    I'm building one for my Theremin and I'm also planning on using it
as a building block for guitar apps by adding suitable signal
conditioning...

    I f you wan't one or more, please E-mail me off list and express
interest. I'm getting quotes on the board price... but expect it will be
between $10-20 depending on how many people want one. This is a one time
offer... I'm not in the PCB business, just want some for me, and figure
maybe you do too...

email harrybissell at prodigy.net

H^)