In the
past and maybe still, 27 MHz was used in diathermy machines.
Effect????
?
David
KC2JD
?
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There is very little tissue heating at HF.
As you start passing
through Vhf to UHF you have severe issues. Some very
serious tissue effects
can happen at 432. My 432 amp can generate 2KW out.
With big antennas at
those frequencies ERP's in the mega watt range are
possible at ham power
levels.
The original microwave ovens ran around 900MHz well there's
another ham band
too.
You have more problems stopping pacemakers at
HF. I wonder if there could
be any liability at a stop sign if the person
in the car next to you keeled
over because you were trying to work the
7Alpha on 20 meters from the car?
At the old WB0DRL VHF/UHF contest
station they tuned the amps with microwave
leakage detectors, you know the
tool for testing ovens. All the stations
had them. The shack was RF tight,
however when the door was opened the
detectors would all start banging off
the pegs to the CW. Everybody would
scream "Shut that door"
I
declare Ham Radio is completely safe. What? (Battle Cry heard from the
LT
as you charge the enemy with only a knife in your teeth) YOU WANT TO
LIVE
FOREVER?
BOB DD
-----Original Message-----
From: ham_amplifiers@yahoogroups.com
[mailto:ham_amplifiers@yahoogroups.com]
On
Behalf Of badgerscreek
Sent: Wednesday, January 10, 2007 5:34 AM
To: ham_amplifiers@yahoogroups.com
Subject:
[ham_amplifiers] Re:hi power mobile
I think those Yellow Top Batteries
are called Optima Batteries?
I dont know why nobody is concerned about
having their brains so
close to the antenna? I mean sitting in the near
field of the antenna
running 1 or more kilowatts at the higher frequencies
would have me
worried. Maybe the adrenalin rush is more potent than
worrying about
your health, or maybe theres no
danger?
Greg
--- In ham_amplifiers@yahoogroups.com,
"craxd" wrote:
>
> --- In ham_amplifiers@yahoogroups.com,
"pentalab" >
> wrote:
> >
> >
--- In ham_amplifiers@yahoogroups.com,
1800 Toll Free
> > > wrote:
> >
>
> > > It's kind of funny watching the thread about the mobile
> amplifiers
> > and
> > > voltage
requirements.
> >
> > ##### I have zero experience with it.
I was just waiting for
> you
> > to come out of the wood
work.... since I knew you guys had this
> down
> > pat... and
was all old news. The deep cycle communications
> > batteries work
pretty good.
>
>
> Right now, they're running those yellow
top batteries with the spiral
> cells. They claim these to be the best.
Also, there's really no limit
> to the batteries that you parallel
together to get the power required
> you need. The more batteries, the
longer you can run. I've seen the
> big 24V batteries used in diesel
rigs too ran in these set ups. The
> ones you want have the largest
amp-hour ratings.
>
>
> >
> > ### I also read
in an old QST... where they would use 2 x
> > batteries in
series.... like those used in golf carts..... but one
> > was 6 V...
and the other was 8 V. [didn't even know u could get
> > deep cycle
batteries... big ones... in 6 + 8 V ] Then ur car
> > regulator
would charge em to 14 .3 V.... then with engine OFF....
> > ur
small 706-mk-2-G would last way longer. That setup was also
> > used
in some Field day event's.
> >
> >
> >
>
>
> > > They use a charging system consisting of a 24 volt
alternator,
> and
> > run
> > > parallel /
series combos of standard car batteries (or standard
> > and deep
> > > cycle, if they are smart) to have a 24 volt electric
system.
> One
> > > alternator, and a pair of batteries
will power quite a large
> > system, as
> >
> >
### Don't some of em use train alternator's ??? Think they
> > were
split stator, dual rotor.... or split rotor, dual stator...
> > made
by Neville Leece.... at 1000 A per stator ?? Or was this
> > for the
tube setups ??
>
>
> They'll use like 6 of the Leece
Neville alternators under the hood to
> power the big solid state amps.
Some have used generators that can
> provide 115/230 Vac too ran off
the belt.
>
>
> >
> > ### I still haven't
seen any detailed website on this hi power
> > mobile stuff. Trying
to generate the power is a huge project in
> > itself. RFI, etc...
Rf decks... is another issue. You are
> > right... hams are just
trying to reinvent the wheel.
>
>
> Right, not a lot has
been published on this as it was all done sort
> of under the table
away from the FCC.
>
>
> >
> > Later... Jim
VE7RF
> >
> >
> > > --Toll_Free
> >
>
> >
>
>
> Best,
>
>
Will
>
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