[HCARC] Antenna

[Kerry Sandstrom]

Hi Harvey,

Do you have a few details on the particular G5RV antenna you're thinking 
about.  There seem to be more than a few versions.  Also any info on the 
feedline/matching sections used.

I have a MiniNEC G5RV model that runs on NEC2 with no problems.  It is one 
someone else created and published.  It is a center fed 102' long and 50' 
off the ground.  Unfortunately, the SWR plot showed over 10:1 across the 
whole band on 80 meters..  By the digital portion of the band I assume you 
mean 3580 kHz and by the upper SSB band I assume you mean 3900 kHz and up.

3580 - 3900 kHz is an awful lot to expect.  My vertical which is about half 
size for 80 meters and is fairly simple design (HF2-V) does a good job from 
3500 - 3530 kHz.  If I feeling lucky I can sometimes get up to 3540 or so. 
Thats with a 2:1 SWR.  I think the best you could ever expect is about 100 
kHz bandwidth with a full size dipole on 80 m.  For a G5RV with its sub-size 
and crazy feed scheme, I believe you would be lucky to get 50 kHz for a 2:1 
SWR.

The broadband dipoles such as thye B&W broadband dipole is notoriously 
lossy, like -6dB and is fullsize on 80 m.  Loss appears to be from the 
"matching circuit" at the feedpoint.

If I was in your situation, I would have a two parallel dipoles connected at 
the center.  One would be cut for 3580 and the other for 3950.  Yoiu could 
probably cover 50 kHz or so around both those frequencies with a 2:1 SWR.

Have fun,

Kerry