Dual Band Verticals for 80 and 40 meters - de N4KG
The HF-2V is full size (or nearly so) on 40M but base loaded on 80M.
Base loading is the LEAST efficient method of loading, resulting in a
low feed impedance and narrow bandwidth. My friend KZ4V has an
HF2V with 120 radials 33 ft long which works well on 40M but she
struggles on 80M with this antenna. Her new 90 ft high inverted vee
and vertically polarized Delta Loop are much more competitive on 80.
I like the design of the relatively new and unknown MFJ-1792 80 / 40
vertical. It is full size on 40M with a loading / isolating coil and
tophat
on top for 80M. Top loading is the most efficient form of loading.
This antenna is reasonably priced at $160. Two users have reported
good results with this antenna on Towertalk.
The GAP verticals are inductively loaded by a "transformed" reactance
on the lowest band of operation which reduces efficiency on that band.
For an excellent review see page 75 in the January 1995 issue of QST.
Most users express displeasure with performance on the lowest
band of operation.
( I have no affiliation with any antenna manufacturer or retailer. )
de Tom N4KG
............................
On Wed, 26 Nov 1997 00:19:42 -0800 "KE8RO" <ke8ro@comp-res.com> writes:
>Would like to receive comments from anyone currently using this
>vertical or
>anyone with past experience with it, good or bad. I only have a small
>lot
>and my crank-up tower is maxed out and I would like to purchase a
>vertical
>just for 40 and 80 meters, having a beam for the other bands. I would
>like
>to take it on my next trip to Iceland also, for operation up there.
>Any
>comments would be much appreciated!! Please send any suggestions or
>comments to my address listed below.
>
>Thanks!
>
>73,
>Phil KE8RO
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