Ham Radio . Magnum Experimentum
Antennas, experiments, engineering and other articles of interest to radio folks.
The topic of lightning protection of our radio equipment and everything else in our homes wisely comes up often in the various ham related email lists on the Internet.
A particular thread on one of these lists spoke of ways to disconnect coax, rotator control lines, etc. at or near where they come into the building. One implementation described by some fellow used relays to disconnect things so he could through one switch and instantly isolate his radios from the antennas.
An amusing video is on YouTube describing the state of affairs of ham radio and its operators.
Note the shifty, or perhaps thoughtful, eyes of Burt.
The topic of balanced to unbalanced converters is broad, detailed and deserving of study to apply them where needed. However, this post will discuss the simplest balun of all… the Choke Balun.
Many balun designs convert impedances 1:1, 1:2, 1:4, 1:9 and up.
A close look at the DX Engineering RR8-HP eight port coax switch with lots of pictures including interior views.
If you are fortunate enough to have equipment to measure return loss of your antenna system here is a chart that will convert the return loss in dB to SWR…
The BigIR antenna from Fluid Motion looks like a winner, but there are some concerns about the 80 meter option.
During Field Day 2008 we carefully observed what operating modes the young teens did and did not enjoy while they operated. Without a doubt the digital modes, especially PSK31, got their attention.
The older of the two, KJ4FAJ, in the picture above said this when he made his first PSK31 contact just after midnight during Field Day…