The apex was at about 50 feet on my tower, and the ends were about 20 feet off the ground. Not quite an inverted Vee, but close...
With the ends lower than the center, it certainly qualifies as an inverted vee in my book. But a 40m dipole
with a 30' drop between the center and the ends would mean the included angle was just a bit over 60 degrees,
making the wires too steep for good efficiency.
Am I off track here, or would I be better off with the simpler dipole/inverted vee?
As always, the answer is, "it depends".
The EDZ could be matched reasonably well with a 4 : 1 balun and about a 10uH coil in series with each
wire. (Adjust as needed.) If your primary interest is NVIS propagation for relatively local contacts, and
perhaps medium-distance contacts broadside to the antenna, then the EDZ might be a good choice. But
for DX the inverted vee is likely to be better. Here's why:
First, we'll assume that the EDZ is also installed with the feedpoint at 50' and the ends at 20', and the
comparison will be an inverted vee with the same support points. (That means that the ends of the wires
are extended with ropes and tied off in the same place as the EDZ.) The maximum current on the EDZ legs
will be 1/4 wave up from the ends, or about 32' (1/4 wavelength) off the ground. At this height maximum
radiation will be upwards due to ground reflections. By contrast the maximum current point is at the feedpoint
of the dipole - we have to reduce the effective height a bit due to the wires sloping downward, but that
still puts us around 40' or so. While the inverted vee is still capable of reasonable NVIS coverage at this
height, it will also have better low angle radiation due to the increased height.
If you have a specific interest in one direction and can install the EDZ broadside to that direction, it might
be an improvement at some distances. Likely it would also be better for NVIS at distances out to 100 miles
or so (when the ionosphere ever gets around to supporting such modes again...) But for general use I think
the inverted vee (with a flatter angle than the one you had) will be better overall. Whether it is better than
your slopers for DX will depend on ground losses, etc.
[edited to use coils instead of capacitors]