[AMRadio] AM IARU Bandplan


D. Chester k4kyv at charter.net
Wed Mar 10 23:41:46 EST 2010


> I have enough of a time keeping the BEASTs reined in at 1500W PEP.  If I
> set the microphone resting current at the specified in the TM at 40ma,
> the darn thing WILL hit 2500W PEP.
>
>
> Bob - N0DGN


Bob, what are you using to measure your PEP?

All the stock BC-610's I ever worked on back in the 60's and 70's would just 
about make 100% on positive modulation peaks before flat-topping. This is 
inherent to the factory design because of the modulation transformer 
step-down turns ratio.  If the 610 is run according to the TM's instructions 
(also saving the 250TH from premature failure), you run 2000v on the final 
at 250 milliamps for 500 watts DC input.  This optimistically gives about 
350 watts carrier out, based on the (optimistic) assumption of 70% 
efficiency. No way that stock BC-610 could even make 1500 watts peak power, 
let alone 2500 watts.

That's why the FeeCee deleted the requirement that hams have "accurate 
instruments" to measure power when they changed over to the p.e.p. 
bullshi'ite.  As stated in their own Report and Order, they knew it would be 
unrealistic to expect the average hammy hambone to be able to accurately 
measure power output with commonly-used instruments and typical hammy 
technical knowledge (and remember, that was during the era when the average 
amateur radio operator was still expected to actually know something about 
what was inside his "box" and how it worked).

>From what I constantly hear over the air, to-day's hams seem about equally 
obsessed with two things: peak power and SWR. Both are way overblown beyond 
their actual significance.  I suspect a lot of hams have an inflated idea of 
how much power they are actually running, using a typical el-cheapo hammy 
hambone wattmeter, combined with grand delusions of "Strap".

Don k4kyv
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