----- Original Message -----
From: "Steve Katz" <stevek@jmr.com>
To: "'Lamb'" <k7fm@teleport.com>; <JimMoci@aol.com>; <amps@contesting.com>
Sent: Tuesday, February 12, 2002 3:48 PM
Subject: RE: [AMPS] Thanks for BIRD meter info!
>
>
>
>
> > "Don't forget that to measure VSWR, you need a slug for "reflected"
> > reading
> > that's several times more sensitive than the one used for "forward"
power.
> > If you're a Bird user, you already knew that...!
> >
> > 73, Steve, WB2WIK/6"
> >
> > Do you mean that forward power is not supposed to equal reflected power?
> > I
> > thought 1:1 was what we were trying to achieve. How are we going to
heat
> > the shack if all the power goes elsewhere? If the power leaks out of
the
> > antenna, most of it is wasted - because it goes where no one is. If it
is
> > reflected, I know where all of it goes.
> >
> > Colin K7FM
> >
> ::Colin, you seem to have it all under control. But you might
> consider placing the short circuit directly at the amplifier output to
> realize the full benefit of this, thereby rendering the coax and antenna
> superfluous. By saving money on feedlines and beams, you can invest in
> higher powered amplifiers, no?
>
I have an even better spin on this... you can save even putting the short
circuit on the outside and even needing RF drive to energise it!
Disconnect the antennas, feeders, HF rig (driver) - you can sell them
all if you wish - just adjust the grid bias volts down to increase Izsac
until it reaches Pdiss for the output tube(s) of your amplifier.
No RF drive is required! No EMC/TVI problems! Plenty of heat for
the shack! I must try it with my 8877 6m amplifier - should equate to
about a 1.5KW heater (3000V @ 500mA).
Mike G8TIC/M0VHF
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