First of all please let me introduce myself. My name is Des (M0AYF) and
am currently a qrp H.F. operator (just a hint of qro :-) with an interest in
L.F. I have only been on the mailing list for a few days since I only
learned of its existence quite recently.
If I may I should like to ask one very important and practical question, is
it possible to make contacts effectively at 160 kHz with a proposed antenna
which would only be about 25 feet high and about 50 foot long (horizontal
wire or "T" resonated against ground) as this is about as much as I could
ever manage within the garden of my town semi. In other words are there any
operators on the list who are currently working with an antenna system with
these sort of dimensions.
Des,
Several successful LF operators use small antennas, though it can
be frustrating when listening to the big boys working DX. A Marconi
T antenna will work well when tuned against a good earth. If you
are able to get a light weight loading coil at the top of the vertical
section this will help (use a 3 litre coke bottle). You will benefit
from running high power - the beauty of the limit being ERP is that
you can compensate for an inefficient transmit antenna by
increasing power. The BK Electronics amps are useful for instant
QRO, though the G3YXM and G0MRF amps are more elegant.
Although a basic T will work, there is lots of scope for ingenuity in
bending an antenna to get the maximum amount of wire, carrying
the maximum amount of current. Mine is triangular!
Also, spend as much time on the Rx system as the Tx. The most
successful stations can hear well - and there are lots of 'deaf'
stations out there - and some of those with smaller antennas have
succeded by being able to hear lots of possible QSO partners.
You are unlikely to do well from Day One, but patience and
persistence in gradually improving your station will bring great
rewards. I have twice heard people describe LF contacts from small
antennas as "the most exciting in years of operating" and this is
my experience, too.
My own antenna is bent into 60ft long by 40ft high - bigger than
yours but smaller than many - and I have had more than a year of
very exciting experimenting, making improvements and ultimately
working several countries.
Good luck and I look forward to working you.
73
Mike, G3XDV (IO91VT)
http://www.dennison.demon.co.uk/activity.htm
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