Presentation: DIY digital Theremin

Finished soldering the parts and testing the hardware. From the beginning i can hear something. Following with the scope the signal is clear until before the end, there i have to change  something. LFOs are working and i can change (first test!) with the antennas pitch and volume! Some things are not working yet, but they will

Do you have any ESD protection for the antenna circuitry?  If not, you might want to add it, or at least socket the IC's and such that are exposed to potential ESD damage.

"Do you have any ESD protection for the antenna circuitry?  If not, you might want to add it, or at least socket the IC's and such that are exposed to potential ESD damage."

 Sockets, are you serious?

"Sockets, are you serious?"

Plenty of Theremins have bit the dust over ESD. 

Testing the CV Outs i killed one OPAMP. Wrong part choosed, but the pinout of the new one is identical - easy repair. There i should have used a socket ;). The Midi In/Out is working and the Line Out/Headphones Sound is quite nice, but not finished yet.

In the future everyone can use socket if wished. I dont use sockets.

Everything works again. For testing I am sending at Midi Out a Value, receiving it at Midi In. This Value - an LFO - I am sending to the CV Outputs und modulate the frecuency of the Audio output. It seem to work perfect, disconnecting the Midi cable everything stops.

But I have to replace the optokoppler with another type because it is not suited for 3.3V although its working. I tested also the Midi In/Out with the computer and it worked.

One of the next steps is to build a platform with right dimensioned antennas to test the behaviour.

Here a first sound example, played on a 8cm big pitch antenna and a 1cm big volume antenna.

Yes, yes, there is still some noise in it - but I'm sure, i will get rid of it :).

You here a mix of 1/8 original signal an 7/8 pitch corrected signal. Its base frequecy is a sine wave. The second frequency is a sine-wave at 1/4 volume and double frequency. The third frecuency is a sine-wave at 1/16 volume, 4x frecuency and 25% phase. And the last frecuency is a sawtooth, 6x frequency at 1/64 volume.

The scale is major pentatonic.

https://soundcloud.com/user-522556810/theremin-first-sound-example

In my opinion a good result for one week debugging. :)

That is quite an accomplishment, are you sure you were not playing a piano?

You have good knowledge that I may tap into.

Christopher

Curby, your audio sample is way too pitch quantized for anyone to judge anything by it.

""Sockets, are you serious?" Plenty of Theremins have bit the dust over ESD."

 So... what's ESD???? Is this something I should worry about with any Theremin? Built, being built or otherwise?