"Chuck James" wrote in message
t...
I know I could just go buy a mag-mount mobile antenna, but would it be
possible or even practical to build a J-pole type or vertical (without long
radials) antenna for 2m/70cm, out of welding rod, which could be small
enough to be easily portable and used inside different rooms? Our local
RACES is trying to set up a volunteer communications network inside several
different city and county offices to assist in emergencies. I have
searched (a little) for such a design, and found something similar, made
out of TV line, but would prefer something that could be made free standing
and as small as practical. The Welding Rod antennas made with 45 degree
radials are a little bulky to move through congested hallways. The idea is
to make it portable enough to move from room to room as needed. Long
radials would impede moving through hallways.
Thanks in advance, KE5GEO



Yes you should be able to build one out of welding rod. I built mine out of
brazing rod and an N connector. It is an open stub design where the bottom
end of the matching section is open instead of shorted like most designs and
is fed from the bottom. 3/4 wl part is connected directly to the center pin
of an N connecter, short side is connected to the outside of the N
connector. Seems to work OK but it got to be a real pain and probably a
saftey hazard "put your eye out kid". Finally made an in-door antenna
modeled after a 60s 70s style pole lamp. SImplest version was a piece of PVC
pipe about 8 ft long that you wedge between ceiling anf floor and tape a
dipole to the antenna. I think I still have a wooden one around somewhere
that uses pieces of a tape measure for elements..