Re: SSTC As a transmitter.

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

Original poster: "Gary Peterson by way of Terry Fritz <twftesla-at-qwest-dot-net>" <glpeterson-at-tfcbooks-dot-com>

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Tuesday, July 23, 2002 8:22 AM
Subject: Re: SSTC As a transmitter.


>
> Original poster: "Jan Wagner by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<jwagner-at-cc.hut.fi>
>
>
> > Original poster: "Mike Panetta by way of Terry Fritz
> <twftesla-at-qwest-dot-net>" <ahuitzot-at-mindspring-dot-com>
> > Now that would be cool!  I had actually had a similar thought, working a
> > ham band with an SSTC, but I was not sure of the legality of it.
>
> A sstc qso would be great, Tesla would've probably liked that. :)
>
>  http://www.amrad-dot-org/projects/lf/
>
> At least doing CW with the TC is something that should work extremely
> well!! Keying done by switching the mains supply (switch before the
> rectifiers and small smoothing caps) on and off => no key clicks.

I'd think a well filtered DC power supply or a bank of batteries would be
better than an AC supply.

> The ham available LF bands are between 70 and 190kHz (depends on your
> country), so that'd be very well "reachable" with any medium-to-larger
> sized TC secondary coil.

Here in the U.S. we have the license-free 160-190 kHz band for QRP
experiments--right now.  Input to the final stage must be limited to one
watt and there are antenna height restrictions as well.

> Does anyone know what power levels are allowed? If it is 120W or more,
> then we're talking business!  :-)
> SSTC-DX, the new way of intercontinental DX. That'd be cool... :o)))

They're talking about 100 watts peak envelope power (input to the antenna
transmission line).  BWT, does anyone know what the impedance of a typical
master oscillator might be?, i.e., what impedance does the lower end of a
magnifying transmitter's extra coil see, looking towards ground?  Richard
Hull says it's low, but how low?

> For voice transmission, I'd "think" that power modulation (corresponds to
> AM modulation, right?) by pulse width modulation of the SSTC drive signal
> would give the narrowest output bandwidth and "cleanest" signal. I might
> be wrong, of course, as I've never tried this out. :-)

I've never tried modulating my SSTC either.

> By the way, the TC should better not produce any streamers, because
> then Q would be abysmal i.e. loaded TC sec == broadband band pass filter.
> And the resonant frequency ("carrier") would be pretty unpredictable too.
:-(

I concur.

> hmm...
>
> cheers,
>
>  - Jan
>
> --
> *************************************************
>  high voltage at http://www.hut.fi/~jwagner/tesla
>
>
>
>

Regards,
Gary