>> I was mobile QRP (5 watts) this past weekend, while crossing USA in
>> automobile. 10 meters was hot, lotta DX. I was was surprised by a
>> number of sounding stations. A lot of high powered stations in Europe,
>> Asia and Carribean were overdriven (obviously amplified) and had their
>> audio so compressed and overloaded that it was painful to hear. I
>> suppose that they believe that they have what it takes to crack
>> through the QRM. It was hard to hear stateside transmissions, but I
>> noted that they also tended to the same extreme.
>
>The FT1000MP's of a contestor I looked at had the internal power
>limit pots cranked up so the FT1000MP's would run 150 watts.
>
>SSB IM products were over fifteen dB worse in the radios at 150
>watts than at 100 watts, and I expect the radios are operated that
>way quite often during contests.
? Yea, verily, Tom. Such feculence is a common plague on CB as well. A
work-around is to increase the DC supply V to the radio *And* turn up
the ALC/ P-limit adj to increase current. This procedure keeps
Volts/Amps in the proper ratio so the that the Collector [or Drain]
waveform does not clip and make rotten splatter. Since 12VDC radios are
typically rated for 11V-min./16V max, and their output transistors are
typically 18VDC-rated units, this causes no problem.
- Editorial -- someday, car manufacturers may wake up and realize that
48VDC electric systems reduce the amount of copper needed by 75% compared
to 12V electric systems. With a 48V electric system, a 1.5 kW HF mobile
amplifier becomes a practicality.
- The transistors used in high power AM broadcast stations run on 70VDC
(W6RU)-- the same as the Apollo moon-lander. Mo' than 6 or 12 volts is
mo' betta.
>...
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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