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Pic chip interlock to midi interupter board only.

PostPosted: Mon Mar 18, 2013 3:12 pm
by E.TexasTesla
You could put a small pic 12f629 between fiberoptic input and the rest of the one tesla board.
It could be programmed to wait for a specific data signal from the midi board.
When it saw the correct midi board it would start to pass thru all signals.
Else it would lockout coil. Would be good if you wanted to reduce possible abuse from incorrrect interrupt.

Re: Pic chip interlock to midi interupter board only.

PostPosted: Mon Mar 18, 2013 9:12 pm
by Bayley
If you're concerned about ambient light triggering the coil, we haven't found that to be an issue (though obviously you should still take appropriate safety precautions, e.g. plug in the interrupter cable on both ends, then plug in the main power cord). Otherwise, you should only tinker with the interrupter (or use your own interrupter) with the full knowledge that it might destroy the coil.
We could add a hardware limiter on the coil end, but that reduces the versatility of the board; e.g. with a change of transistors, the driver might be able to drive a much larger, slower coil at low BPS and high currents - something that couldn't happen if we added hardware PW limiting to the interrupter input. Similarly, a hardware PW limit on the interrupter end would limit the board's versatility; right now, it is a pretty general optocoupled interrupter that you can use for a DRSSTC, or for a high-duty-cycle SSTC, or for something else (I've used it to modulate a YAG laser before!)

Re: Pic chip interlock to midi interupter board only.

PostPosted: Wed Jun 12, 2013 10:07 pm
by Bill Porter
I mentioned this to the team during the kickstarter run. They are confident in their fuse protection and additional parts would drive up the kit cost.

Though better than a PIC or any uC, would be a simple Low-pass filter and compator for over-duty cycle protection. Adjusting the 'trip point' would be a simple trim pot, allowing future upgrades to beefier parts without being limited by safety hardware.

I've used the exact same fiber parts in coil control before, have had it activated by light and my coil was safely shutdown by the above mentioned duty cycle safety system. Though it was during an outdoor event and it was triggered by sunlight.

Re: Pic chip interlock to midi interupter board only.

PostPosted: Sat Aug 17, 2013 8:39 pm
by E.TexasTesla
I'm expanding on the pic chip ideal.

What if the pic chip looked for a certain signal which would tell it to turn on an aux. igbt or scr to bypass the tank capacitor. This could switch the coil from drsstc to sstc mode for higher frequency notes.

Just a thought.