Software signal generator ...

[poynt99]

There are many small signal high voltage NPN transistors that would do the job. The 2N3904 is probably not the best choice here anyway with its relatively low VCE of 40V.

I might try the MPS8099, as it has a VCE of 80V, similar to the 2N3055. If you are not using a flyback diode across the coil, be sure to use protection across the transistor C-E so as not to exceed the VCE rating. Bedini uses neon bulbs, but they fire at about 90V if I am not mistaken.

.99

[allcanadian]

@deepcut
Sometimes the simplest answer is the best one, buy a set of cheap computer headphones then cut one of the speakers off and glue it onto the other one so they are facing one another with a spacer tube between them. When the output speaker from your computer moves the speaker you just glued onto it must move with it and acts as an AC generator, a coil moving in relation to a magnet. Use a signal diode off the second speaker to produce a DC output which can be used to energize a signal transistor or mosfet. Now this may seem rather crude but it does one thing exceptionally well, it offers a means of complete electrical isolation as the energy transfer media is air between the speakers. If you are triggering HV impusive currents it is only a matter of time before a HV transient wipes out your electronics, your sound card and possibly the motherboard of your computer through the most unlikely of paths and this simple system will protect your computor like few other circuits can. I have seen 1/2" arcs across isolation transformers which have wiped out my triggering electronics and they will also wipe out most all other electronics within the common ground path. In fact some of my circuits have produced violent cracking noises inside my old oscilloscope a few feet away when the scope leads were not attached to anything which was a little scary,lol.
Regards
AC

[poynt99]

Here is something that should get you in the ballpark.

Neon2 is an extra line of protection for your PC or generator in case Neon1 does not fire. I would also recommend incorporating the flyback diode, unless the design calls for this being absent.

.99

[nievesoliveras]

@allcanadian

Is this what you mean?

[DeepCut]

Thanks AC that's a highly-inventive solution. I'm not yet using HV but when i do i'll remember your post.

.99 thanks very much for that, i'll set it up tomorrow and tell you how it went.


Thanks again,

Gary