[Lf] [Fwd: LF: Tesla Coil as an antenna]

[Andre Kesteloot]

Tom Tishken KD4WOV wrote:

> Yes, keeping the sparks from flying  is one major concern i was having. I
> had a primary coil that resonated very well at 138 KHz, but I never finished
> making a secondary coil. Other than a Large globe atop a large secondary
> coil, has anyone else found a way to keep it from arcing?
>
>   Second question, should we try to drive it with high voltage (400 to 1200
> volts and very little current) or should we drive it with low voltage (12 to
> 24 volts and 10 to 40 amps). The primary coil I was using would withstand 12
> volts and 30 amps, I cooked it when I went to 37 amps.
>
>   Third question, For all you LF antenna guru's. should I use stranded or
> solid copper, steel, or aluminum wire. I know each one has good and bad, but
> what have you all had better luck with?
>
>   I have thought about keeping the primary coil in mineral oil for heat
> dissipation, any suggestions about cooling of the primary? What do you all
> use to keep your LF antennas cool?
>
> -----Original Message-----
> From: majordom at post.thorcom.com [mailto:majordom at post.thorcom.com]On
> Behalf Of James Moritz
> Sent: Tuesday, January 29, 2002 11:05 AM
> To: rsgb_lf_group at blacksheep.org
> Subject: Re: LF: Tesla Coil as an antenna
>
> At 09:14 29/01/2002 -0500, you wrote:
> >Hello,
> >   I have not experimented in a while with my partially built tesla coil,
> but
> >has anyone used their Tesla coil as an antenna for ELF or other Freqs? If
> we
> >try to use it for 137 KHz how do you determine ERP?
> Dear Tom, LF group,
>
> Well, occasionally I have inadvertently used my LF antenna as a Tesla coil
> :-) But seriously, The Tesla coil is essentially a helical antenna (see
> ON7YD's LF antenna web pages  http://www.qsl.net/on7yd/136ant.htm ). So if
> it is several metres tall, and you can persuade it to resonate on 136kHz,
> it might make a usable LFantenna. Of course, you would want to avoid the
> discharges that occur in the normal Tesla coil mode of operation, since
> these generate QRM and absorb lots of RF power.
>
> Cheers, Jim Moritz
> 73 de M0BMU