SideBand wrote:
Reg Edwards wrote:

"SideBand" wrote in message
m...

Anyone out there know of any decent solution to getting 160M working in
a mobile? The application is a semi-truck. I've got the Iron Horses for
75, 40, 20, 15, and 10M, but I'd like to work something out for 160
meters that will work on the truck.

I know I'm going to take an efficiency hit, but you're doing that for
everything except 10M on a Semi anyway.. Just so I can get a signal out
there to be heard, in the off chance.

ANY suggestions or ideas would be greatly appreciated.

73 de AI8W, Chris


=============================

For design and performance of a 160 meter band vertical antenna, download
program HELICAL3 from website below. There are other loaded vertical
programs..

Use 1.5" or 2" diameter plastic pipe, with helical winding of thick
enamel
insulated wire, mounted on vehicle roof, as tall as possible, stayed,
with
short, top caapacitance tuning rod.

Range on 160m with a few hundred watts = 100 miles at noon on
groundwave.

1700 miles on very quiet, wiinter nights at midnight via F-layer.
----
.................................................. .........
Regards from Reg, G4FGQ
For Free Radio Design Software go to
http://www.btinternet.com/~g4fgq.regp
.................................................. .........


Reg:

Thanks for this.. it'll help allot..

Question, though.. What should I put down for "earth electrode loss
resistance"? I'll be using the truck's body as the ground plane.

I'd just thought about doing this with a 2 foot (or so) 2 inch PVC pipe
with end caps, feed point at the one end of the PVC, and a 102" whip out
the other end. Now that I know this program exists, it's easier to think
about! Since the SS whips are tapered, what would be a good guess for
the diameter of it? Average it to 3mm? Or will it make that much of a
difference?

Thanks

de AI8W, Chris

I know.. bad form to reply to your own post...

Got something here I think will work...

Resonant at 1.903
h=.61
d=510 (around 2", plus the insulation thickness.)
n=28
w=3
l=2.49
r=3
e=5 ohms

Makes for a 4.6kHz bandwidth (not wide, but I knew that going into
this...) with an efficiency of 2.4 %.. 16.2dB down from "ideal", and
50ohms (or close) with a 4.1uF cap.

Of course, this is assuming that the whip doesn't have to be
perpendicular to the centerline of the coil. If it can be parallel to
the coil (perpendicular to the winds), then this might work... I hope.

I'm gonna play with it some more, and see what I can dig up.. Maybe a
larger coil form will give a wider bandwidth?

de AI8W, Chris