Subject: Re: Power, signal surges in home...
From: emd@ham.almanac.bc.ca
Distribution: world
Organization: Robert Smits
Lines: 48

clewis@ferret.ocunix.on.ca (Chris Lewis) writes:

> In article <1r1jmoINN8mb@rave.larc.nasa.gov> kludge@grissom.larc.nasa.gov (Sc
> >In article <DRAND.93Apr20150701@spinner.osf.org> drand@spinner.osf.org (Doug
> >>In article <randall.735251839@woof> randall@informix.com (Randall Rhea) wri
> 
> >>   Hams can legally run up to 1500 watts.  It is very unlikely, however,
> >>   that a ham would be running that kind of power from a car.  Ham rigs
> 
> >>Not possible either.  You'd need about a 300 amp alternator for
> >>just the amplifier.  I can just see it.  You need to slow
> >>down on a downgrade,  so you hit the push to talk button.
> 
> >Now, that indeed is possible.  A good friend of mine is running about 1 KW
> >PeP from his car.  Yes, he does have a second alternator.  Yes, he calls
> >the rig an "electronic brake" since the engine noticeably slows when the
> >key is down.
> 
> It has been a while since I knew the electronics of ham radio, but I seem
> to remember that PeP is actually 4x the "real" power.  Which makes 1KW PeP
> actually around 250W.  Or was it 2x?  I disremember.
> 
> "Effective transmitted power" is also "odd", in that it takes into account
> antenna height and geometry.  Which is why a TV station with a 50KW Klystron
> might advertise a megawatt (if their antenna is on the top of the
> CN tower ;-).
> 
> This is like Sears HP ;-)
> 
> Though, 1500 real watts still isn't impossible.  About 125-150A with
> a 12V alternator, less if the alternator produces higher voltages.
> 
> It's only three horsepower (taking into account inefficiencies).  You'll
> feel it when you hit the key.  But not too much.
> -- 
> Chris Lewis; clewis@ferret.ocunix.on.ca; Phone: Canada 613 832-0541
> Psroff 3.0 info: psroff-request@ferret.ocunix.on.ca
> Ferret list: ferret-request@ferret.ocunix.on.ca


It sorta depends on what you drive. I remember running a two channel 
Motorola with a vibrator power supply and about 40 tubes in a 1958 
Volkwagen. The poor little 6 V generator had a heck of a time, and if you 
keyed the mic at night, you needed to be stationary, because your lights 
got AWFUL DIM. Isn't progress wonderful?


emd@ham.almanac.bc.ca (Robert Smits Ladysmith BC)
