Dear Cecil,
Here is something very nice you could do for all of us. How about making
a table of xmission line lengths and capacitor values for folded dipoles
fed with 300 ohm twin lead? I used to build these when I was a kid (many
moons ago) and used a parallelmica xmitting cap (surplus of course) to
match the line to 50 ohms. It could then be easily fed with a 1:1 balun.
Honestly though... I never used baluns in those days. I just wound up
the coax around a coffee can and fired away.
Makes a nice broad antenna... easily matched and very cheap to build. TV
twinlead is
certainly fine at QRP levels and available everywhere. What could be
easier?
I made such a table a few years ago but I lost it. I can see how much
you enjoy antenna building (hot stove and otherwise) and I thought you
might enjoy providing this table to some of the younger folks who may
never have heard of this 'trick'.
By the way, those folded dipoles were fairly easy to tame with a matchbox
so one cut for 80 would work pretty well on all bands. How about giving
it a go, Cecil?
Something like:
Frequency Dipole length(twinlead) Xmission line length
(twinlead) Cap value
-------------- -------------------------------
------------------------------------------ -------------
You get the idea... I am sure. Thanks in advance.
vy 73,
Martin QRP-L # 998
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