[ARC5] Best coupling method.

[Mike Hanz]

Kenneth G. Gordon wrote:

>My personal opinion on the BEST method of coupling the 
>ARC-5 to a "real" antenna is Mike Hanz' Un-Un.
>

Well, I can't claim it as mine, but it works well for me because all I 
have in the shack are WWII aircraft sets, which tune a relatively small 
and well understood parameter window.  Note that it doesn't preclude the 
need to condition the typical ham antenna to something approximating a 
resistive condition - the series cap or other tuner is still needed to 
minimize losses in the UNUN and feedline.

They are certainly not the only way to do the job...even with a 
broadband core and <100 watt power levels there are small losses in the 
transformation.  The main reason I like them is that running open wire 
with a lot of RF around the shack isn't such a good idea for a number of 
reasons.  For authenticity' sake I can run a short section of ceramic 
bead covered Copperweld wire to a black wrinkle painted box containing 
the 4:1 UNUN and then use RG-231 to the antenna patch bay, where it 
transfers to hard line out of the shack.  I use the 4:1 ratio because it 
is the least lossy of the various ratios available that gets the 50 ohm 
impedance down to a manageable 12 ohm value that all the transmitters 
can tune.  That makes the RF ammeters in most of them sit up and dance 
again, as well.  YMMV, especially if you have no interest in the 
authenticity perspective.

Best 73,
Mike  KC4TOS