An interesting number:
If Jim's measurement of MM0ALM's field strength is right, at 50 uV/m, and
assuming the distance between them is 600 kms mainly over a standard
medium-conductivity land path then :
According to the CCIR standard propagation curves (Vol 5, "Propagation in
non-ionised media", Recommendation 368-4) a radiated power of 1 kW at 136
kHz from a short vertically-polarised monopole would produce a field
strength at Jim's distance of 500 uV/m.
Jim measured 50 uV/m so MM0ALM's radiated power must be 10 dB below 1 kW -
100 watts. Jim's measurements I have found to be pretty accurate in the
past but if anyone else can make accurate field strength measurements
perhaps they would do so next time MM0ALM comes on.
I've made my own measurements and they agree with Jim's. I've also measured
field strengths of a number of "local" stations and knowing exactly what
they're using for transmitters and antenna systems the results tie up
pretty closely (including, by the way, confirming G3AQC's statements about
his power). NONE of the locals I measured were exceeding 1w radiated.
What people choose to radiate is up to them and the RA but let's not have
any boasting about DX worked when they've been using illegal powers. They
should note that, as per above, and unlike HF, it is not that difficult to
estimate pretty closely what they're radiating - one advantage of basing
the licence on radiated and not "DC input" power. Of course, if MM0ALM
holds a "high-power" NOV then good luck to him but he should declare it.
Might also be worth noting that any DX records made while using illegal
powers are invalid and will not be recorded.
Perhaps anyone who thinks he's being slandered would publish full details
of his transmitter, antenna and earth system and let others make their own
judgements. Far better than just hurling insults around.
Walter G3JKV.
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