zamproject
Well-known member
- Joined
- May 11, 2010
- Messages
- 1,597
Hello
This is a side question topic about the Ondioline I'm currently restoring.
Late 50' tube... who guess ! (The Ondioline)
There is a "percusive" element consisting of a coper braid that you push to a copper bar in front of the keyboard assembly, work just like a contact switch.
The safety issue is that this system directly drive the control grind of the preamp pentode,
meaning the voltage going to this "switch" users can touch is directly derivated from HT, with two 500k voltage divider, HT/2, 140VDC....
I don't want to rewire it as original and I'll probably mod the circuit I design few years ago for the touch detection of my moving fader system. I can easy hook a relay or an optocoupler on this system.
What would be your suggestion to do a remote SPST switch on a 140VDC control signal ? I suppose it need to be fast, below ms response, and without possible bounce
Best
Zam
This is a side question topic about the Ondioline I'm currently restoring.
Late 50' tube... who guess ! (The Ondioline)
There is a "percusive" element consisting of a coper braid that you push to a copper bar in front of the keyboard assembly, work just like a contact switch.
The safety issue is that this system directly drive the control grind of the preamp pentode,
meaning the voltage going to this "switch" users can touch is directly derivated from HT, with two 500k voltage divider, HT/2, 140VDC....
I don't want to rewire it as original and I'll probably mod the circuit I design few years ago for the touch detection of my moving fader system. I can easy hook a relay or an optocoupler on this system.
What would be your suggestion to do a remote SPST switch on a 140VDC control signal ? I suppose it need to be fast, below ms response, and without possible bounce
Best
Zam
