[Elecraft] How Long Is "Long Enough"?

[Sandy, W5TVW]

I agree with this logic!  After trying a raft of antennas QRP portable, the 
random wire is the best and most efficient for the amount of labor expended 
getting it up.
Be SURE to use radials!  Even if you are in a motel room and have to run 
them around the edges of the room!  Outside, I have found that two radials 
33' long seems to work very well on 40 thru 15.  Use four if possible, just
laid on the ground.  I use #24 gauge stranded MIL spec white hookup wire.
The kind with the tracer stripes on it.  WHITE wire aids in keeping people 
from stumbling on it.  For an 'antenna', I use a 25-33' wire strung up in a tree
or other support.  Normally I use a BNC to binding post adapter (Pomona)
connect the radials to the shell and the antenna to center conductor.  In most
cases, no need for any balun.  Use at least two radials.  The KAT1 tuner
will work OK without radials but the radiated power will suffer!
On 80 meters double all the wire lengths.  The shorter ones WILL work, 
but at much reduced performance.
    My "QRP portable" antenna kit consists of a spool of small nylon 
cord (Seine line), several 1/2 oz and 1 oz "teardrop" lead sinkers
painted Day-Glo orange (makes the easy to find in the grass!),
6-8 lengths of hookup wire 33' long.  With this you can toss the weights
over tree limbs by hand.  I sometime carry a collapsible spinning
rod and reel as well.  It works better than the simple "hand toss"
for getting the weights over high limbs.  Some people like the 
slingshot method.  What ever turns you on.
My portable QRP goes back to the TenTec ""Powermite" modules,
the PM2, PM3, Argonaut, Heathkit HW-7/8/9, now the Elecraft K1,
which is the best one I've used so far for a small rig!

73,
Sandy W5TVW
| Weymouth Walker wrote:
| 
| > The subject is: the "shortest" dipole I can get by with 
| > when operating portable with the K2 ...
| 
| 
| Weymouth,
| 
| One possible answer is: use a random-length vertical rather than a
| dipole. A piece of wire of any gauge (I use #26, usually) can be tossed
| into a nearby tree. In many cases this is simpler than putting up a
| dipole--you can get on the air in literally seconds if you keep a weight
| attached to the line. It will often outperform a low dipole on
| lower-frequency bands.
| 
| Another advantage of the random-length vertical is that you can get by
| with no feedline, especially if you have a balun available. Instead of
| using the balun to convert unbalanced to balanced, use it just as a way
| of providing some isolation between the K2's chassis and the antenna.
| Eliminating the feedline is the key to minimizing the fiddle-factor in
| getting an antenna up.
| 
| I've loaded wires as short as 20' on most bands using the KAT2. Avoid
| lengths that are an exact multiple of a half wave on any band you plan
| to use. Bring a few extra hunks of wire to lay out as radials. 
| 
| 73,
| Wayne
| N6KR