Re: Portable antenna suggestions for forthcoming QCX mini


ajparent1/KB1GMX
 

There are at least 3 or more vendors making that style of antenna these days.
Generally for field use 10 is like 6M right now, line of sight use mostly.

The big two is 40 and 20, and that is fairly easy.  30M is popular for data
and CW so for some that has appeal.

The wide band transformer with either a linked wires or several cut to band
wires is light and easy.  Traps do not work for voltage fed antennas (EFHW)
unless you get lucky and put them at a high current location.  Then you will
go nuts getting the lengths right.  Stubs and chokes are generally used.

At home the ideas are different.  My PAR/LNR EF-quad at 66ft long 
and larger box for a 100W transformer makes sense there.

For laughs I built a QRP power level wide band transformer using FT68-61
for about 1:49, in a very tiny plastic box with BNC and thumbscrew to attach
the wire.  That  added to 10ft of RG316 with BNC, and two pieces of wire
for 20 with knife disconnects for adding length for 40.  Plus a two coils of
0.050 paracord about 50ft each.  All in a small pouch that can hang from
a belt or velcro to the back of the FT817 the Mic is in a similar pouch
velcroed to the radio. all up weight is maybe 6 ounces, maybe less.  A
pocket sized 5AH lipo and its a portable radio system.  QCX and key plus
battery would be lighter.

IF you making it the various recipes are well known and some work
better than others.  Built is for the application as its easy to make
a bigger or smaller one.  One note the differnce between a big airdux coil
and a wideband ferrite transformer is near impossible to determine from
communications distances.  The losses can be measured but rarely is
it enough to make a difference.  The overall height of the wire however
does makea differnce.

The thing to keep in mind is all that makes little sense if the location is a hike
to it and high with a small QRP monoband CW radio and a tiny battery!

IT was never clear is the users application save for monoband.

Allison
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