Hi Peter,
At open sea QRM (man made noise) levels are likely to be low (apart from
what you generate on your vessel). So I wouldn't worry about QRM.
But the main advantage of /MM operation is that the loss resistance (the
main factor that determines antenna efficiency at LF) is extremely low
By using the steel vessel as counterweight the loss can be less than a few
Ohms, at land it is in the range of 30 ... 150 Ohm at 136 kHz.
Your main problem might be to make a low loss loading coil, as the loss of
a typical loading coil (on 136 kHz) is in the range of 5 to 20 Ohm.
73, Rik ON7YD
At 14:44 14/01/2004 +0100, you wrote:
Hi all,
I am 100% new to LF.
I lack any LF experience at all at the moment.
Nevertheless, I consider to take a chance on LF.
Does it make sense when I try to start LF from my ship /MM ( steel
fishermen cutter ) instead of from my condo ?
Does sea again ( if any at all ? ) and low man made en evironment noise add
substantially to the LF performance ?
( Besides, on my vessel I could erect bigger aerials than at the home QTH ).
Where could I find explanations on (possible ) sea gain on LF ?
Where could I find information on the ( LF ) noise levels offshore ?
Thanks for your appreciated thoughts.
Peter, PE1ECM
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