Starting point for the inverted L with sloping top loading wire.

45' high, 25.8' sloping wire at the top, 29 feet high at the far end. #12
THHN Insulated copper wire, stranded. Mounted 7" above the earth, directly
to a 3' ground rod (strictly for mechanical support, as I had a prefab mount
with 3/8x24 on one end and SO-29 on the other)

Predicted Radiation Resistance (Devoldere): 25.8 ohms, very good ground
(rich pastoral, midwest).


I see I had confused feedpoint impedance and radiation resistance (after
reading some more in Devoldere's "Low-Band DX'ing")

According to Figure 9-94, the radiation resistance for my inverted L is
approximately 25 ohms. According to EZnec 4.1, source data says:

Impedance = 25.58 + J 1.872 ohms at 3600 khz.

When I measure the antenna with the MFJ-269, I get:

R=37 and X=0

If Devoldere and EZNEC are correct (although EZNEC may or may not be
measuring radiation resistance), then my radial-less inverted L is showing
ground losses of 37-25=12 ohms. If so, then my efficiency, without radials
is:
25/(25+12) or 25/37 or approximately 67%.

Before installing radials this morning, I just want to make sure I'm looking
at the right variables and interpreting them properly. 4 radials, laying on
the ground, will be ready to install when the sun comes up. 4 more later in
the day, etc., up to a total of 16 (the amount of wire I have ready to go).
Each time I put down 4, I'll take another measurement with the 269. For
kicks, I might take a measurement with just one or two first.

....hasan, N0AN