Author Topic: OpenTheremin v3 for Tesla Coil  (Read 619 times)

Offline profdc9

  • High Voltage Technician
  • ***
  • Posts: 186
  • Karma: +6/-0
    • View Profile
OpenTheremin v3 for Tesla Coil
« on: May 29, 2018, 07:01:20 PM »
So I built my theremin and while it works, it is not the greatest.  As predicted, the RC-based theremin is a good noisemaker but is hard to control.

So instead, I am going to modify OpenTheremin v3 to directly be an interrupter.  I laid out the board for thru-hole, which I have attached.  A picture of the board is here:



Since there are no thru-hole varactors anymore as far as I can tell, I used four 1N4001 in parallel which roughly has the same capacitance as the varactors used in the OpenTheremin (BB914).

I also got rid of the Arduino and just put the Atmega328 on the board itself, as well as the power supply, so it is self contained, and I added a circuit to output the MIDI.

Dan

Offline Mads Barnkob

  • Administrator
  • High Voltage Senior
  • *****
  • Posts: 851
  • Karma: +7/-0
  • Denmark
    • View Profile
    • Kaizer Power Electronics
Re: OpenTheremin v3 for Tesla Coil
« Reply #1 on: June 01, 2018, 03:16:23 PM »
Did you get any videos done of using the RC theremin on a DRSSTC?

Did you use the MIDI "hack" that someone else already made for the OpenTheremin?
http://www.kaizerpowerelectronics.dk - Tesla coils, high voltage, pulse power, audio and general electronics

Offline profdc9

  • High Voltage Technician
  • ***
  • Posts: 186
  • Karma: +6/-0
    • View Profile
Re: OpenTheremin v3 for Tesla Coil
« Reply #2 on: June 01, 2018, 04:12:22 PM »
I haven't got any video yet, I am behind in my work because I have been playing too much :) but maybe this weekend if the weather cooperates I can get some video.

I added a couple of things to the board.  One is an output for the MIDI using the TX of the AVR (which does double duty as if the ATmega328p is flashed with the Arduino bootloader, you can use a serial port interface to flash the mega as well).  I also added a LM386 to the board so you can get a low power amplified output directly from the board, and you don't need an external amplifier if you just want to use it as a portable Theremin.



The revised project is attached.

Dan

Offline profdc9

  • High Voltage Technician
  • ***
  • Posts: 186
  • Karma: +6/-0
    • View Profile
Re: OpenTheremin v3 for Tesla Coil
« Reply #3 on: June 28, 2018, 04:01:13 AM »
Hello,

I built an OpenTheremin v3 based on only thru-hole parts.  The PCB is below.



It works, but I had to experiment a bit to find diodes that work as varactors.  Unfortunately, there are no available thru-hole varactors anymore.  I figured out that I could use three 10A10 diodes in parallel in place of the varactor.  I'm sure it wouldn't work for RF, but it seems to do ok for the Open Theremin.  I had to use three 10A10 diodes and then add 50-100 pF of capacitance in parallel with that, and then the autotune works.  I modified the board so it can take large diodes in case these are needed as the varactors.

The board I laid out also includes MIDI output (hooked up to a DIN-5 connector) and a small amplifier (LM386), as well as putting the ATMEGA328P on the board so an Arduino Uno is not required.  There is also a place for a IFE97 fiber optic LED which will be used for generating an interrupter output.  It should be possible to modify the standard OpenTheremin v3 to have an interrupter output, as I'm just going to retask one of the LEDs as the interrupter output (the green one).

Probably the 10A10's are less temperature stable than the BB914 diodes but after 15 minutes or so of being turned on the calibration stabilized.

One question I have about the OpenTheremin is that it seems like the volume is muted by putting one's hand closer to the volume antenna.  Is this the way it is supposed to be?

Anyways the Kicad project is attached.

Dan





Offline futurist

  • Global Moderator
  • High Voltage Technician
  • *****
  • Posts: 116
  • Karma: +0/-0
    • View Profile
Re: OpenTheremin v3 for Tesla Coil
« Reply #4 on: July 01, 2018, 03:00:17 PM »

One question I have about the OpenTheremin is that it seems like the volume is muted by putting one's hand closer to the volume antenna.  Is this the way it is supposed to be?

Yes, it should work like that

Firmware has debug mode and I think it's still not documented, but it might help you to see if everything is working correctly. If you open the serial window in Arduino IDE and set 115200 baud rate and then start the calibration of your theremin you should get the calibration data.  Calibration range is from 0-4096 and you can check if your oscillators are in the range

Did you test it with your DRSSTC?


High Voltage Forum

Re: OpenTheremin v3 for Tesla Coil
« Reply #4 on: July 01, 2018, 03:00:17 PM »

 


* Recent Topics and Posts

post Re: My First DRSSTC
[Dual Resonant Solid State Tesla coils]
Hydron
Today at 11:07:22 AM
post Re: My First DRSSTC
[Dual Resonant Solid State Tesla coils]
sjsimmo
Today at 08:08:58 AM
post Re: How to calculate VA rating and other things for Ferrite Core? (SMPS)
[Transformer (ferrite core)]
sjsimmo
Today at 01:24:15 AM
post How to calculate VA rating and other things for Ferrite Core? (SMPS)
[Transformer (ferrite core)]
FilipŠebík
January 18, 2019, 07:32:38 PM
post Re: How to design a 7.5kV AC source?
[Transformer (ferrite core)]
profdc9
January 18, 2019, 04:25:14 PM
post How to design a 7.5kV AC source?
[Transformer (ferrite core)]
CristianM
January 18, 2019, 03:48:06 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
the_anomaly
January 17, 2019, 02:01:36 AM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
petespaco
January 16, 2019, 04:26:38 AM
post AC vs DC fuses, high current, explosive destructive testing and theory
[Capacitor banks]
Mads Barnkob
January 15, 2019, 09:48:48 PM
post Re: My X-Ray Machine
[X-ray]
neukyhm
January 15, 2019, 10:51:46 AM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
petespaco
January 14, 2019, 05:08:38 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
the_anomaly
January 14, 2019, 01:15:53 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
Mads Barnkob
January 14, 2019, 12:22:07 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
petespaco
January 11, 2019, 05:10:39 AM
post Re: My X-Ray Machine
[X-ray]
Max
January 10, 2019, 10:59:25 PM
post Re: 迎词、来
[General chatting]
profdc9
January 10, 2019, 06:56:59 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
petespaco
January 10, 2019, 05:33:48 PM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General chatting]
black.yang
January 10, 2019, 02:11:58 AM
post Re: My X-Ray Machine
[X-ray]
Mads Barnkob
January 09, 2019, 09:14:59 PM
post Acoustic spectra of sung vowels by the FFT analyzer HP 3561A
[Electronic circuits]
Physikfan
January 08, 2019, 08:44:16 PM
post Re: IGBT failure in DRSSTC
[Dual Resonant Solid State Tesla coils]
Felix Bieri
January 08, 2019, 05:33:55 PM
post Re: Huawei RRU3928 1800MHz radio base station teardown (part 1 of 2)
[Radio frequency]
Mads Barnkob
January 08, 2019, 08:25:08 AM
post Re: SimpleDriver v2.3, my phase-shifting QCW DRSSTC controller
[Dual Resonant Solid State Tesla coils]
flyglas
January 08, 2019, 08:25:02 AM
post Re: SimpleDriver v2.3, my phase-shifting QCW DRSSTC controller
[Dual Resonant Solid State Tesla coils]
Hydron
January 08, 2019, 02:01:50 AM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Hydron
January 07, 2019, 10:23:38 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Laci
January 07, 2019, 08:53:32 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
petespaco
January 07, 2019, 08:17:44 PM
post Re: SimpleDriver v2.3, my phase-shifting QCW DRSSTC controller
[Dual Resonant Solid State Tesla coils]
Netzpfuscher
January 07, 2019, 07:37:53 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Uspring
January 07, 2019, 01:30:36 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Laci
January 07, 2019, 12:43:26 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Hydron
January 07, 2019, 08:09:49 AM
post Re: SimpleDriver v2.3, my phase-shifting QCW DRSSTC controller
[Dual Resonant Solid State Tesla coils]
NEYi
January 07, 2019, 07:43:50 AM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General chatting]
Mads Barnkob
January 07, 2019, 06:48:06 AM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Mads Barnkob
January 07, 2019, 06:39:56 AM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Laci
January 06, 2019, 09:23:19 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
petespaco
January 06, 2019, 07:11:25 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Uspring
January 06, 2019, 07:02:14 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
flyglas
January 06, 2019, 12:43:46 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Laci
January 06, 2019, 11:55:09 AM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
TDAF
January 06, 2019, 09:48:06 AM
post Re: First SSTC build, need help troubleshooting
[Solid state Tesla coils]
TDAF
January 06, 2019, 09:45:17 AM
post 关于: 这个便宜的 drsstc 驱动程序从 aliexpress 1.3 b 类型?
[Dual Resonant Solid State Tesla coils]
black.yang
January 06, 2019, 08:34:46 AM
post 迎词、来
[General chatting]
black.yang
January 06, 2019, 08:20:21 AM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
flyrod
January 06, 2019, 12:34:15 AM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
petespaco
January 05, 2019, 05:27:23 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
flyrod
January 05, 2019, 03:46:29 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Laci
January 05, 2019, 09:51:10 AM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Mads Barnkob
January 04, 2019, 11:02:25 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Laci
January 03, 2019, 08:38:15 PM
post Re: SimpleDriver v2.3, my phase-shifting QCW DRSSTC controller
[Dual Resonant Solid State Tesla coils]
flyglas
January 03, 2019, 08:15:48 PM

Sitemap 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30