TopBand: 160 Flag & Pennant

[Bob Marshall-Read]

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Topbanders,

I sent this to Earl K6SE after a revamp of the receive antenna array.
Maybe it will be of some interest to those without a large antenna farm.

The flag and pennant both perform well and I am hoping to pick up some
southern hemisphere countries this summer using the new receive system.

73

Bob   G4VGO  EI7IU


Earl,

I have built a flag and a pennant for my 140' X 55' yard.  The pennant goes
to the west for the N/S America path, and I put the flag due south as the
pattern seems to cover all but the north pole and eastern GM's from the QTH
on the Suffolk coast north east of Ipswich.

Because of XYL issues, I have mounted them just off the ground, but the 9:1
transformers I made from ferrite rods and the RG59 seem to match everything
within a few tens ohms from 1.8 to 6.8 MHz.  The F/B on the western pennant
is apparently very good.  I use one of my former array of shielded loops as
a 'bench mark' and on A/B with stations in Europe and the USA the 4 S units
front to back are almost as predicted.  As far as the south facing flag, the
GM stations off the back, and some of the very western scandanavian stations
are well down, but Africa, Europe, and eastern Med stations are just as
strong as on the amplified and phased loop array, and the S/N is better as
there is no need for a pre-amp on the flag.

I use 20dB of pre-amp on the pennant with a 4-1.6 MHz bandpass filter at the
low impedence feed of the pennant and the S/N is still superior to the array
of phased loop.

With clutter as the attenuator/isolator (a house made of brick), the two
antennas do not appear to interact being 90 degrees to each other......and
the inverted L transmit antenna at the far corner of the lot has not caused
any problems with the pattern of the RX antennas.  Just guess I got lucky,
or haven't noticed.

US W7's are now plesantly readable as are the sometimes hard to hear W5's
and W0's. EL2WW was two S units stronger on the flag than the phased loops.

In short, down come the loops, and I will now be flagging and pennating
through the summer.




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