Hi Dave: One look at the specs for WD-1A scares me. I do not see how one
could successfully send any RF down one of these wires as a differential
transmission line. That is exactly what happens, and what you need in the
reverse Beverage mode. The loss of WD-1A at 4kHz can be as much as 5 dB per
mile by spec. Lets see thats about 1dB at 4kHz for the average length Beverage.
1000/5280 * 5 dB=~1dB. Using a simple 1 dB for each doubling (2^9 * 4khZ) of
the frequency as the spec chart shows, one can expect 9 more dB for a total
loss of at least 10dB. It would likely be much worse than this in real loss
figures for the cable at 2Mhz. 10dB loss or more in the reverse direction
would be very noticeable. I am not certain what it would do to the expected
operation/pattern but I am sure it would affect the real versus theoretical
termination resistance of the antenna as well. Some real loose approximations
here! It is not hard to expect this when it has an approximate 70 ohm trans
mission line impedance (my guess) and a pure DC loss resistance of 46 ohms in
1000 feet per side!
So let me guess, you see 1 to 2 S-units (6 to 12 dB) difference in antenna gain
forward to reverse?
Here is the specs when it was new. What it might be after 10 or 20 years maybe
more is anybodys guess.
Oh, and SWR would likely look pretty good as there is a lot of resistive loss
here.
"http://www.dscc.dla.mil/Downloads/MilSpec/Docs/MIL-DTL-49104/dtl49104.pdf";
Personally, I would not use this wire.
Lee K7TJR Oregon
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