Dear JB (no call sign): The objective was in no way intended to stifle,
only to describe.

Here is the essence of my message about the 1080 of about a month ago:

It is deceptive to put numbers on the size. The reflector consists of five
doublets each with a tip-to-top length of 26.5 inches and a total height of
a little over 16 inches. The twin "driven" elements are spaced about 6.6
inches in front of the reflectors (obviously the reflectors are only
effective for UHF). The tip-to-tip length of the driven elements is about
34.5 inches (giving a predicted 0.5 WL resonance towards the bottom of the
higher VHF TV band). Each driven element is coaxial with a fan dipole that
should have a resonance somewhere in the UHF band. Thus one expects a small
gain with a small F/B in the higher VHF band and fair gain with good F/B in
the UHF band.

Regards, Mac N8TT

--
J. McLaughlin; Michigan, USA
Home:
"JB" wrote in message
news:F7vnk.521$EL2.235@trnddc01...
Sorry about that. I did get them mixed up not having the photos in front
of
me when writing. Roy is also correct. All that is in the ARRL Antenna
Handbook. I believe impedance is lowered though at the dipole elements
apex. to some extent. The dipole vs. Inverted V comes to mind, but the
feedpoint impedance of a LPDA is really about the spacing of the feeders
and
matching system. .

I'll shut up now

"J. Mc Laughlin" wrote in message
.. .
I am looking at a 1080. It is being used in the computer room. All of
the
elements are in two, parallel planes that are each normal to earth. In
other words, flat. On high-VHF (channel 12, here) there is little F/B
ratio, but that has not been a problem. The chances of needing to reject
a
high-VHF station (at 180 degrees) on the same frequency is slim. The
antenna is a stout, little, two-bay broadside array with reflector mostly
effective on UHF.

I provided a detailed set of measurements in another message. 73, Mac
N8TT

--
J. McLaughlin; Michigan, USA
Home:
wrote in message
news
"JB" wrote:

While the 1080 UHF is fairly sharp with some potential gain, the VHF
elements seem to be little more than "rabbit ears" - In fact it is a
swept
dipole, so will be bi-directional and easily pick up reflections from
behind
and around you..

I'm a bit confused on your remark above.

Looks to me like the 1080 is perfectly flat antenna.
Where do you see any bending or sweeping of elements?