SIDAC Spark Substitute

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Peter Terren" <pterren@xxxxxxxxxxxx>

This is a proof of principle coil rather than a big performer. It uses 
SIDAC's in place of a spark gap (As I use spark gaps, which is with the 
tank cap across the supply rather than the spark gap across the supply). 
These are symmetrical breakdown devices which act similarly to a sparkgap.
Info: 
<http://www.onsemi.com/pub/Collateral/MKP3V120-D.PDF>http://www.onsemi.com/pub/Collateral/MKP3V120-D.PDF 

The SIDAC's cost US$1.33 each in 10 quantity at Digikey. 
<http://dkc3.digikey.com/PDF/C041/0618.pdf>http://dkc3.digikey.com/PDF/C041/0618.pdf

As set up at present it is driven by a MOT transformer with the associated 
11kV diode and 0.95 uF 2KVAC cap wired as a voltage doubler to provide 5.6 
KV or so. This is dumped by a SIDAC or rather 22 in series each shunted by 
1 megOhm.  Each SIDAC is rated to breakdown at 240V and has a 1A RMS or 20A 
pulse capacity.  The string of 22 SIDAC's will nominally breakdown at 5280V.

Also shown running ignition coils (with much better performance) 
<http://tesladownunder.iinet.net.au/Other_HV_stuff.htm#Ignition coil 
sparks>here.

This might have application for small coils running low voltages where 
spark gaps become problematic, but without the complexity of an SSTC.

Pics at 
<http://tesladownunder.iinet.net.au/Solid%20State.htm>http://tesladownunder.iinet.net.au/Solid%20State.htm 
showing 2 inch sparks.

I guess this could be called a SIDAC Spark Substitute Solid State Tesla 
coil. (SSSSSTC!)

Peter (Tesla Downunder)
<http://tesladownunder.iinet.net.au>http://tesladownunder.iinet.net.au