Topband: 160m inv vee questions

[Bill Tippett]

FYI in response to two recent threads:

http://lists.contesting.com/archives//html/Topband/2018-03/msg00139.html
http://lists.contesting.com/archives//html/Topband/2018-04/msg00043.html

This plot shows my low inv-V (30m apex is only 0.19 wavelengths) compared
to my 3 element parasitic vertical.  Study the relative gain vs TOA plots
carefully:

http://lists.contesting.com/archives//html/Topband/2018-03/msg00139.html

My observations over the past 14 years comparing both:

1.  The vertical array is best 99% of the time.  Usually by ~10 dB to the
NE (e.g. EU/W1 from here).  From the plots you can see this equates to TOAs
(<20 degrees).

2.  The inv-V (wires running NNW/SSE) is occasionally (1%of the time) much
better to EU or other directions at my local sunset or sunrise.  This is
striking when it happens and is easy to detect since the inv-V is also
better for RX than either Beverages or an RX4SQ.  This is clearly some sort
of high angle mode around SR/SS and it usually lasts for <30 minutes.

3.  The inv-V BW is much broader than the vertical array which is very
narrow (~30 kHz).

4.  TX antennas are separated by about 100m on different towers and the 30m
inv-V height is near optimum for maximum radiation straight up
(intentionally).

5.  The inv-V also works well to the SE (Caribbean/SA) even without SR/SS
enhancement.  I have no idea whether how it would behave if rotated 90
degrees since my site doesn't allow for that.

Just FYI,

Bill  W4ZV