Arrgh! I confused this thread with a recent one asking about UHF TV
antennas. My response wasn't at all appropriate to this discussion.

I agree completely with Richard Harrison, a quadrifilar helix is
probably a good choice for this application.

I sincerely apologize to Richard and other readers for my carelessness
and mistake.

Roy Lewallen, W7EL

Roy Lewallen wrote:

Because one of the very important functions of a TV antenna is to reduce
multi-path interference causing fading and ghosting, directionality is
essential. The quadrifilar helix I'm familiar with is a normal-mode
helix; that is, the maximum radiation or reception is broadside to the
helix, and it has an omnidirectional horizontal pattern when the axis is
vertical. That would be a poor choice for a TV antenna. . .

Roy Lewallen, W7EL wrote:
"I confused this thread with a recent one asking about UHF TV antennas."

I understand. My strugle with TV reflections involved antennas atop the
corporate headquarters. We had to have a perfect color picture in the
executive lounge and there was no cable yet. The founder, chairmman and
CEO was proud of his luxury and toys. We had a lot of signal, but too
many signals due to other skyscrapers around ours. With sharp enough
antennas we were able to clean up the mess. Better a hero than a goat!

I think I was very lucky today. I had typed the previous posting and was
about to hit the send button when the electric power failed. I was sure
it would mean retyping. However, when power was restored, I wert to the
archive and found it in storage. Hooray!

Best regards, Richard Harrison, KB5WZI

This is it ! http://members.aol.com/k5oe/ The Eggbeater2 guys, I
think ?

.. After reading Gerald's information on how to construct this antenna
I was left unclear about the dimensions table and all the digits shown
there.

1) What do they stand for, and how to apply them in the construcion of
the antenna ?

And another thing:

Is there any spacing between the loops when they cross eachother on
top and on the bottom ?

How about the reflectors, they must be spaced out if they cross
eachother inside the boom ? How much is the space ?

Thank you very much again.

Phil

"philnyc" wrote in message
oups.com...
This is it ! http://members.aol.com/k5oe/ The Eggbeater2 guys, I
think ?

. After reading Gerald's information on how to construct this antenna
I was left unclear about the dimensions table and all the digits shown
there.

1) What do they stand for, and how to apply them in the construcion of
the antenna ?

And another thing:

Is there any spacing between the loops when they cross eachother on
top and on the bottom ?

How about the reflectors, they must be spaced out if they cross
eachother inside the boom ? How much is the space ?

Thank you very much again.

Phil

Phil

You might search on "Cebik". He shows very good information on how to
build a Moxon Rectangle Turnstile.

Jerry

. After reading Gerald's information on how to construct this
antenna
I was left unclear about the dimensions table and all the digits
shown
there.

1) What do they stand for, and how to apply them in the
construcion of
the antenna ?

And another thing:

Is there any spacing between the loops when they cross eachother
on
top and on the bottom ?

How about the reflectors, they must be spaced out if they cross
eachother inside the boom ? How much is the space ?

Thank you very much again.

============================

Would you like him to come along and build it for you?

"Richard Harrison"
I understand. My strugle with TV reflections involved antennas atop the
corporate headquarters. We had to have a perfect color picture in the
executive lounge and there was no cable yet. The founder, chairmman and
CEO was proud of his luxury and toys. We had a lot of signal, but too
many signals due to other skyscrapers around ours. With sharp enough
antennas we were able to clean up the mess. Better a hero than a goat!
_____________

Here's another war story. Many Chicago TV stations moved to the new Hancock
Bldg to use one of the RCA antennas that were stacked there on two masts.
When one of the big network O&O stations flipped the switch to start using
this new site, the on-air picture at their studio turned to absolute
garbage, right in front of all the executive staff gathered in a boardroom
to celebrate. The studio was located about four blocks from the Hancock
Bldg, and close to the null in the elevation pattern of the new 2-bay
antenna they had switched to. Most of the RF they could pick up was from
reflections. I think they finally installed a very high gain antenna skewed
upward up at a large elevation angle focused at the top of the Hancock Bldg,
but the best picture they got was never very good.

RF (RCA field supervisor during the installation
and commissioning of the TV antenna systems)