PIC Based VTTC Staccato Controller

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Andy Cleary by way of Terry Fritz <teslalist-at-qwest-dot-net>" <cleara-at-twcny.rr-dot-com>

Hello All,

	As the subject suggests, I recently tried my hand at building a VTTC
Staccato Controller based on the Microchip PIC 16F84 microcontroller.
In it's current form, the PIC allows for a highly variable pulse
output by selecting one of 3 options, and then varying them up or down
(via 3 pushbuttons).  The options are:

1) Change % of AC cycle ON (pulse-width per cycle)
2) Change number of ON-cycles and
3) Change number of OFF-cycles.

where by "cycle" I mean the AC cycle at the input to the VTTC.

The microcontroller is very nice for reducing the complexity of the
board layout and thus easing construction time.  Another possible
advantage to the microcontroller approach is the improved noise
immunity, I had no problems at all with false triggering etc.  One
possible disadvantage, though, is a less intuitive user interface (no
knobs to twiddle).  I experimented with using a rotary encoder for
this, but it didn't pan out.  This difficulty could possibly be
remedied by adding an LCD or 7-segment display, which I plan to do
eventually.

I tried out the breadboarded version the other day on my (barely
working) VTTC and it did indeed alter the spark characteristics.  I
havn't actually built one of the "Original" staccto controllers
(Missed the bulk board-order, rats...) so I can't say for sure whether
or not it's working well.  As far as I can tell, it's doing the job.

For more information, Schematics, Code, etc. please see:
http://www.rpi.edu/~cleara/schematics/picstaccato.htm

All comments are appreciated!

Thanks,

-Andy C.

--------------------
Andy Cleary - KC2GVE
RPI Electronics Club President
AJAX Electronics
cleara-at-rpi.edu
GG# 1010
www.rpi.edu/~cleara/
--------------------