TV Aerial Experiment

Lets be silly. Take a commercial yagi TV aerial, take a strip of
cardboard, and make a full size copy of the layout using bits of 2.5mm
T&E cable for the elements, and the cardboard to replace the spine.

How well would it work?


NT

wrote in message
...
Lets be silly. Take a commercial yagi TV aerial, take a strip of
cardboard, and make a full size copy of the layout using bits of 2.5mm
T&E cable for the elements, and the cardboard to replace the spine.

How well would it work?

See
http://www.wrightsaerials.tv/homemade2.htm
http://www.wrightsaerials.tv/homemade3.htm

Bill

In article
..com, scribeth thus
Lets be silly. Take a commercial yagi TV aerial, take a strip of
cardboard, and make a full size copy of the layout using bits of 2.5mm
T&E cable for the elements, and the cardboard to replace the spine.

How well would it work?


NT

It would work .. so would any bit of metal, question is by how much
relative to what;!..

The active elements don't have to be "connected" together. The diameter
of the 2.5. Elements would have an effect on the bandwidth..
--
Tony Sayer

"Bill Wright" wrote in message
...

wrote in message
...
Lets be silly. Take a commercial yagi TV aerial, take a strip of
cardboard, and make a full size copy of the layout using bits of 2.5mm
T&E cable for the elements, and the cardboard to replace the spine.

How well would it work?

See
http://www.wrightsaerials.tv/homemade2.htm
http://www.wrightsaerials.tv/homemade3.htm

Bill

Pleased that you are on this newsgroup. I enjoyed the aerial photos.

"John" wrote in message
...

"Bill Wright" wrote in message
...

wrote in message
...
Lets be silly. Take a commercial yagi TV aerial, take a strip of
cardboard, and make a full size copy of the layout using bits of 2.5mm
T&E cable for the elements, and the cardboard to replace the spine.

How well would it work?

See
http://www.wrightsaerials.tv/homemade2.htm
http://www.wrightsaerials.tv/homemade3.htm

Bill

Pleased that you are on this newsgroup. I enjoyed the aerial photos.

Thank you. I've always been here. They haven't found a way to eradicate me.
And I'm a cult you know. An absolute cult, that's what some of them on here
call me.

Bill

"Bill Wright" wrote in message
...

wrote in message
...
Lets be silly. Take a commercial yagi TV aerial, take a strip of
cardboard, and make a full size copy of the layout using bits of 2.5mm
T&E cable for the elements, and the cardboard to replace the spine.

How well would it work?

See
http://www.wrightsaerials.tv/homemade2.htm
http://www.wrightsaerials.tv/homemade3.htm

Bill


homemade 3 is a stairway to heaven..............

"Bill Wright" wrote in message
...

"John" wrote in message
...

"Bill Wright" wrote in message
...

wrote in message
...
Lets be silly. Take a commercial yagi TV aerial, take a strip of
cardboard, and make a full size copy of the layout using bits of 2.5mm
T&E cable for the elements, and the cardboard to replace the spine.

How well would it work?

See
http://www.wrightsaerials.tv/homemade2.htm
http://www.wrightsaerials.tv/homemade3.htm

Bill

Pleased that you are on this newsgroup. I enjoyed the aerial photos.

Thank you. I've always been here. They haven't found a way to eradicate
me. And I'm a cult you know. An absolute cult, that's what some of them on
here call me.

Bill


Bill,

For the first time ever I have explored some of the more obscure links on
your web site. I'm sad to say I found "Albert's Attic" especially
interesting.

I always knew I was a "latent" anorak. Now I know for sure.

David

tony sayer wrote:
In article
.com, scribeth thus
Lets be silly. Take a commercial yagi TV aerial, take a strip of
cardboard, and make a full size copy of the layout using bits of 2.5mm
T&E cable for the elements, and the cardboard to replace the spine.

How well would it work?


NT

It would work .. so would any bit of metal, question is by how much
relative to what;!..

Tony's right: the good news about yagis is that they "want to work".
Anything that is sufficiently yagi-like will tend to be directional and
have some forward gain, at some frequency or another.

Making them work *well*, and on the frequency that you want to use, is
quite another story.

The active elements don't have to be "connected" together.
The diameter
of the 2.5. Elements would have an effect on the bandwidth..

By removing the metal boom and element clamps, and also changing the
diameters of the elements, you have changed two things that affect the
resonant frequency of each element. This shifts the frequency response
of the whole array. And as for the changes in the driven element, and
how they might affect the transfer of signal into the downlead... you
have no way to know.

If you are aiming to copy an existing Yagi design, you must copy:
* all the element lengths
* all the element diameters
* the element mounting method.
That means: copy EXACTLY. If you change any of these details, you are
actually building a new design. The following page isn't specifically
about TV yagis, but it gives some idea of what's involved:
http://www.ifwtech.co.uk/g3sek/diy-yagi

Sorry, but this really isn't a subject that you can just wander into and
immediately succeed. Unless you have such a strong TV signal that none
of this matters, you'd be better off with a commercial yagi.



--
Ian White

On Thu, 7 Feb 2008 10:10:30 -0800 (PST), wrote:

Lets be silly. Take a commercial yagi TV aerial, take a strip of
cardboard, and make a full size copy of the layout using bits of 2.5mm
T&E cable for the elements, and the cardboard to replace the spine.

How well would it work?

Perfectly well on the single frequency it was designed for. The
diameter of the elements affects the range of frequencies the antenna
will remain effective on so its bandwidth would be less than the
commercial equivalent as the wire is thinner than the aluminium tube.

On Feb 8, 6:03 am, "tpow" wrote:
"Bill Wright" wrote in message

See
http://www.wrightsaerials.tv/homemade2.htm
http://www.wrightsaerials.tv/homemade3.htm

Bill

homemade 3 is a stairway to heaven..............

It is ! As a lad I took Dad's decommissioned Band I/III aerial,
chopped up its elements and converted it to a Group C/D UHF. I was
astounded to discover that simply by pointing out of my ground level
bedroom window, I could receive watchable pictures from Mendip (about
90 miles away).