[MRCA] NVIS antenna for Gilbert

[ersmar at comcast.net]

Gents:

     I tried out the 80M wires of my NVIS inverted V system this afternoon. 
I erected the thing in my ENTIRE front yard, spanning from one street corner 
(I"m on a corner lot) to the fence around my back yard, across the front of 
the house.  I used dacron guys for the other two legs.

     After a bit of trimming, the final wire lengths were 59 feet each.  SWR 
BW (2:1) was about 90 kHz, centered on 3.850 MHz.  I had to use a couple of 
additional fiberglass mast sections underneath the plastic chain that I use 
as end insulators to raise the wire ends farther off the ground.  I think 
Dale or Rob suggested I do that anyway for RF safety.

     At around 4-5 PM today from my Rockville, MD home (a bit north of DC) I 
was able to work into PA (57) and throughout VA (59 - 59+10) with 80 W 
output (my TS-570 was on battery power) on the high end of 80M.

     I haven't tried the antenna with both 40 and 80M wire sets installed 
simultaneously; guess that will have to wait until Gilbert.  If we have to 
save space, I can erect the mast as I did today - only the 80M wires.  It'll 
still be a long antenna system that we'll have to fit in somewhere.

     One other thing:  As I wrote last year, we might have trouble with 
skywave/NVIS propagation on 80M during mid-afternoon on Friday and 
mid-morning on Saturday.  D-layer absorption will be a bear at those times. 
What we really need for 80M is a good ground-wave launching antenna for 
3.885.  Maybe a full-wave, terminated delta loop pointed at the mountaintop 
field site.  But that's for next year.


BCNU es 73 de
Gene Smar  AD3F
P.S  Anybody have the 4-pin MALE DC power connector for my AM-65 amp's power 
cable?  The only place these things were found in gummit equpment was on the 
M-300 mounting base for the AM-65/RT-70 combo.