W dniu 2012-05-01 22:53, Stefan Schäfer pisze:
LF!
Has someone a very good link to basic understanding about LF? I mean
the LF amateur radio stuff, all which one has to learn when starting
rx-wise in our hobby! Maybe some ideas and examples, a good
compliation. Not to complex and focusing on 137 kHz amateur radio?
For newcomers in the "LF-transmit-world" i recommend ON7YD's page
http://www.strobbe.org/on7yd/136ant/
Is there maybe something for receive newcomers?
A collection of some links may help as well...
Thanks in advance.
73, Stefan/DK7FC
Hi Stefan, LF
In my opinion the basic info for ' LF receive newcomers' should be
divided into 3 topics.
While the first one shoud provide knowledge about propagation of long
waves the second one
should provide basic information about modulation techniques used at
LF. The third part might cover
technical ideas/schematics concerning receiving antennae ( either active
or passive), filters, pre/ampifiers
impedance matching issues etc... - here you are an expert... :)
Concerning the modulation techniques i would still recommend the
excellent Rik, ON7YD website but with different page:
http://www.qsl.net/on7yd/136narro.htm#QRSS
IMO, this is the best starting info i have ever found...
According to LF propagation effects - i would definitely ask Alan Melia
for the info upon this issue
For those who like to do little math ( just for fun or for more serious
purposes) i would advice to look at the following paper:
http://www.qsl.net/dk2fi/lw/lfprop1.pdf
those above are just first thoughts etc.... Yours,
Piotr, sq7mpj
qth:/Lodz/
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