Penfold P2V: First success

[stefano]

SOMEHOW, IT STARTED TO WORK !!!!!

PRODUCTION OF SAMPLES AND PHOTOS IN PROGRESS....

Yes, sir, yesterday the Penfold F2V Guitar to Synth Interface started to convert guitar frequencies to voltage. I say "SOMEHOW" because I had to make a little mod (or bypass) to start it work. And I think that the device is not working in the way that Penfold designed it... but it WORKS.

I suspected that the signal path "stopped" at the gates of the quad switch 4016BE (I use a MC14016BCP for IC4). IC4 is driven at pin 13 (control pin) by a signal coming from pin 4 of IC11b, so I wondered what would have happened if pin 1 and pin 2 of IC4 would have always connected (like if the control al pin 13 was always enabled). The easiest way to do this is to **short** pin 1 and pin 2 of IC4. I did it and immediately the circuit started to convert frequencies to voltages.
The mini sound lab accepted the 1V/Octave scale produced by Penfold P2V.
I played an A (5th guitar string), tuned the osc-1 Minisoundlab and VR2 (shift control). Then I played the same string at the 12th fret (1octave up) and I used the VR3 (gain control) to tune the sound from the oscillator.

I didn't win the war, but I think at least a good battle! I'm on my way to completely debug this circuit because I don't actually like this bypass .
Next step I'd like to do with an oscilloscope (any advice accepted ):
- controlling the signal at (IC11 pin 4) = (IC4 pin 13) (after generation of quad switch control signal)
- controlling the signal at IC10 pin 6 (before generation of quad switch control signal)

Stay tuned

[Fernando]

a very interesting quest!

hope to read and listen more soon!

[synthmonger]

<---interested in seeing how this works

[Chrometuna]

Any more progress with this?

[stefano]

Yeah look at the main topic "A NO-MIDI..." .
http://electro-music.com/forum/topic-14921.html

It started to convert P2V even if with limitation (works better if you play guitar around the 6th ot 12th fret)