JPascal,
Can you share a volume control scheme? I am interested in your technical implementation of this part of theremin. You may not share, this is your decision and I will understand it.
Respectfully, MIE
Hello JPascal and MIE,
The volume control does work excellent from what I observe so count me in, with strong interest, wanting to view your clever design.
I have not done any soldering in the past few years but picked up the iron again this week, almost an addiction, I keep telling myself don’t breathe the smoke. When I was a child solder rosin smelled good... like pine sap. I am trying to get some of my theremin claims working for a date in Saint Petersburg, Russia very soon. Her classical voice can be elusive but I am teasing her just enough, it will be our last dance. Will be setting up to do a thermal drift test overnight.
JPascal it will be nice to see some old school electronics that I just might understand and it works.
Christopher
JPascal,
This is really good stuff. I have not worked with them but I think those are NMOS fets? If the parts are readily available I would like to build your circuit and in the process make a PDF with your name on it so it will be etched into the board and others can enjoy your work.
Thank you for your theremin research.
Right now I exploring the Pitch side circuit of my own design. She gave me hell yesterday and today nothing but affection. There is a specific waveform I am after and only then I know she respects my efforts, or is it him?
Christopher
Hello, JPascal!
I tried to pick up the values of the elements on your circuit. Can you tell if something is wrong? Also, I had a number of questions:
1)L21 and L22 is one coil with a tap in the middle or two different coils?
2)Is it permissible to use 2N5484 and 1N4148 in this inclusion?
MIE
D11 is wrong, it must be varactor
JPascal,
Thank you. I have some questions:
First, has anything changed in the pitch scheme?
Secondly, what program did you use for spectral analysis?
Here is the LTSpice file:
http://www.mediafire.com/file/yc3kz1i7uo6j3xz/JFET%2528Volume_Stage%2529.asc/file
MIEcomes, Christopher,
now comes my drawings with the values. To the questions: Both coils in the antenna circuit are solid r.f. choke types. The self resonance doesnt play any role because oscillator is tuned at the serial resonance L1 + L2 with antenna capacitance. For spectral analysis of the a.f. signal I use program spectran. The sweep generator I used here with an oscilloscope is a radio service one RPS 3301 Nordmende. Thank you for posting the Spice file, I will try to import it for testing. Transistors are jFETs, but this type is out of production. They have a 4..5 mA drain current at Vgate=0.
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