[Prev][Next][Index][Thread]
RE: Laser Triggered Spark Gap
A diode laser is unlikely to trigger a gap. The cheapest thing I know of
that would do the job is a nitrogen laser, which emits very short, powerful
pulses of UV light. UV would cause ionization and photoemission where red
light would not. See Bert Pool's homegrown N2 laser at
http://www.ticnet-dot-com/bertpool/n2laser.htm or maybe we can get Bert to shine
his laser on his gap !
Alternatively, UV is produced in a hot electrical spark, like from an
ignition coil. Light from a small spark gap triggering a big spark gap is a
viable design, we used it in the 1980's to trigger CO2 TEA lasers.
Will
> ----------
> From: Tesla List[SMTP:tesla-at-pupman-dot-com]
> Sent: Tuesday, November 03, 1998 00:49
> To: tesla-at-pupman-dot-com
> Subject: Laser Triggered Spark Gap
>
> Original Poster: "Steve Young" <youngs-at-konnections-dot-com>
>
> To fellow sparkers,
>
> This list has a lot of discussion about spark gap performance, quenching,
> etc., which certainly is valuable and needed. For static gaps,
> discussions
> seem to indicate quenching is improved for wider gaps. But a point is
> reached where the gap is too wide for spark initiation. Thus the need for
> a means to "help" a wider gap initiate a spark.
>
> Occasionally the use of triggered spark gaps is mentioned, but the thread
> soon dies. I would think this is an area for experimentation which could
> yield a LOT of benefits. For one thing, the bps could be under our
> precise
> control simply by varying the trigger frequency. If one chose to lock the
> trigger frequency to the AC line frequency and adjust the phase
> relationship, one would in effect be able to duplicate the performance of
> a
> RSG without having to mess with high RPM balanced rotors, etc. Having the
> gap fire when WE want it to instead of when it can no longer resist firing
> itself would make for much better control and scope pictures for some of
> the other testing Terry and others are doing.
>
> The various triggering mechanisms have been touched on in this list.
> These
> can range from pulse generator driven ignition coils to lasers. My
> experiments with SCR driven crummy ignition coils indicates they are good
> for break rates up to at least 800 bps. I don't know how the good GM
> ignition coils perform at higher break rates - anyone have some
> experience?
>
>
> Lasers would have the advantage of being able to simultaneously trigger a
> bunch of aligned series gaps by aiming the beam through all the gaps. I
> suspect some Marx generators are fired that way. But where can the
> cash-strapped experimenter find a suitable laser which can sufficiently
> ionize the air to initiate spark breakdown? The only potential cheap
> sources I am aware of would be to use a $15 laser pointer in a pulse mode.
>
> Would this work? Specifically, can the laser diodes handle microsecond
> pulses of a much higher energy without self destructing? If so, could
> they
> produce enough pulse energy to trigger spark gaps? If so, what would the
> pulse width and peak power need to be? Does anyone know what the laser
> diodes used for tattoo removal, etc. cost and where to get them?
>
> In summary, isn't it time to move toward triggered spark gaps for
> disruptive TCs?
>
> Thanks in advance for your comments.
>
> --Steve
>
>