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).

Good till it rained.

I built many yagis in my youth, and as long as the main dimensions and
connections were right, they all worked. However wood as a boom did tend to
dampen the performance....)ouch)

Brian

--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email:
__________________________________________________ __________________________________________________ __________


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?


NT

"John" wrote:

"Bill Wright" wrote in message
See
http://www.wrightsaerials.tv/homemade2.htm
http://www.wrightsaerials.tv/homemade3.htm

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

It's a crossposted thread doncha know.

--
Dave Farrance

In message
,
Mark Carver writes
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).

In 1967(ish), my parents old 3-element Channel 5 (Band 1) aerial got
trimmed down for the amateur 4m band (~70MHz). I the furthest contact I
made with it was Gibraltar.
--
Ian

On Feb 7, 11:20*pm, "John" wrote:
"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.

Which group?

MBQ

"Mark Carver" wrote in message
...
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).

You should try the one in my loft.. I need 24db of attenuation to avoid
overloading the Philips set's receiver.
Mind you I am only about 6 miles from Sutton and you get a decent digital
picture using a screwdriver as an aerial.

"dennis@home" wrote in message
...


"Mark Carver" wrote in message
...
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).

You should try the one in my loft.. I need 24db of attenuation to avoid
overloading the Philips set's receiver.
Mind you I am only about 6 miles from Sutton and you get a decent digital
picture using a screwdriver as an aerial.

I bet that's because it's a Philips screwdriver...........;-)

Chas

On Thu, 07 Feb 2008 18:17:51 +0000, Bill Wright wrote:

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



Brilliant site Bill!
Hmmm... I guess I must qualify for an anorak myself.

gets coat...
--
Mick (Working in a M$-free zone!)
Web: http://www.nascom.info http://mixpix.batcave.net

"Vortex3" wrote in message
...
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.

Thank you.

Bill

On Thu, 7 Feb 2008 18:17:51 -0000, "Bill Wright"
wrote:


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


I remember making a horizontal yagi to receive RTÉ in Liverpool
on channel 7 back in the sixties.

I'm sure I got the dimensions from Practical Television.

It only worked in the summer the opening season.

That's tropo not pub opening.

"mick" wrote in message
. ..
Brilliant site Bill!

Thank you. Anyone who has pictures of particularly
interesting/wierd/inexplicable/dodgy aerials please send them in.

Bill

"XxXxXX" wrote in message
...
I'm sure I got the dimensions from Practical Television.

It only worked in the summer the opening season.

That's tropo not pub opening.

I see from your signature that you have an interest in quality ales.

Bill

Brian Gaff wrote:

Good till it rained.

I built many yagis in my youth, and as long as the main dimensions and
connections were right, they all worked. However wood as a boom did tend to
dampen the performance....)ouch)

Brian


Thanks everyone! Now I know.


NT

wrote:
Brian Gaff wrote:

Good till it rained.

I built many yagis in my youth, and as long as the main dimensions
and connections were right, they all worked. However wood as a boom
did tend to dampen the performance....)ouch)

Brian


Thanks everyone! Now I know.

Something no-one mentioned here was the lack of a balun which could wreak
havoc with weak digital signals due to standing waves on the cable. The most
popular home-made types these days seem to be the bow-tie + reflector +
balun design.

(kim)

In message , kim
writes
wrote:
Brian Gaff wrote:

Good till it rained.

I built many yagis in my youth, and as long as the main dimensions
and connections were right, they all worked. However wood as a boom
did tend to dampen the performance....)ouch)

Brian


Thanks everyone! Now I know.

Something no-one mentioned here was the lack of a balun which could wreak
havoc with weak digital signals due to standing waves on the cable. The most
popular home-made types these days seem to be the bow-tie + reflector +
balun design.

(kim)

Does the lack of a balun actually cause standing waves on the cable?
--
Ian

Ian Jackson wrote:
In message , kim
writes
wrote:
Brian Gaff wrote:

Good till it rained.

I built many yagis in my youth, and as long as the main dimensions
and connections were right, they all worked. However wood as a boom
did tend to dampen the performance....)ouch)

Brian


Thanks everyone! Now I know.

Something no-one mentioned here was the lack of a balun which could
wreak havoc with weak digital signals due to standing waves on the
cable. The most popular home-made types these days seem to be the
bow-tie + reflector + balun design.

(kim)

Does the lack of a balun actually cause standing waves on the cable?

No but it helps eliminate them )

(kim)

kim wrote:
Ian Jackson wrote:
In message , kim
writes
wrote:
Brian Gaff wrote:

Good till it rained.

I built many yagis in my youth, and as long as the main dimensions
and connections were right, they all worked. However wood as a boom
did tend to dampen the performance....)ouch)

Brian


Thanks everyone! Now I know.

Something no-one mentioned here was the lack of a balun which could
wreak havoc with weak digital signals due to standing waves on the
cable. The most popular home-made types these days seem to be the
bow-tie + reflector + balun design.

(kim)

Does the lack of a balun actually cause standing waves on the cable?

No but it helps eliminate them )

(kim)

Is there a way to make a balun that wouldnt cost more than 10p?


NT

wrote:
kim wrote:
Ian Jackson wrote:
In message , kim
writes
wrote:
Brian Gaff wrote:

Good till it rained.

I built many yagis in my youth, and as long as the main dimensions
and connections were right, they all worked. However wood as a boom
did tend to dampen the performance....)ouch)

Brian

Thanks everyone! Now I know.
Something no-one mentioned here was the lack of a balun which could
wreak havoc with weak digital signals due to standing waves on the
cable. The most popular home-made types these days seem to be the
bow-tie + reflector + balun design.

(kim)
Does the lack of a balun actually cause standing waves on the cable?
No but it helps eliminate them )

(kim)

Is there a way to make a balun that wouldnt cost more than 10p?


NT
Suyrem if you buy the toroids in bulk. Or nick them from scrap items.

wrote:
kim wrote:
Ian Jackson wrote:
In message , kim
writes
wrote:
Brian Gaff wrote:

Good till it rained.

I built many yagis in my youth, and as long as the main
dimensions and connections were right, they all worked. However
wood as a boom did tend to dampen the performance....)ouch)

Brian


Thanks everyone! Now I know.

Something no-one mentioned here was the lack of a balun which could
wreak havoc with weak digital signals due to standing waves on the
cable. The most popular home-made types these days seem to be the
bow-tie + reflector + balun design.

(kim)

Does the lack of a balun actually cause standing waves on the cable?

No but it helps eliminate them )

(kim)

Is there a way to make a balun that wouldnt cost more than 10p?

Yes. I think the ones sold by Maplin cost less than 10p each to make )

(kim)

In article ,
kim wrote:


Yes. I think the ones sold by Maplin cost less than 10p each to make )

I'm sure there was a Wireless World article called "a balun for 10p" - some
40 years ago, I suspect.

--
From KT24 - in "Leafy Surrey"

Using a RISC OS computer running v5.11

On Mon, 11 Feb 2008 14:03:47 +0000 (GMT), charles
wrote:

I'm sure there was a Wireless World article called "a balun for 10p" - some
40 years ago, I suspect.

In that case wouldn't it have been "for 2/-"?

;-)
--
Frank Erskine

In article ,
Frank Erskine wrote:
On Mon, 11 Feb 2008 14:03:47 +0000 (GMT), charles
wrote:

I'm sure there was a Wireless World article called "a balun for 10p" -
some 40 years ago, I suspect.

In that case wouldn't it have been "for 2/-"?

;-)

make it 36 years ago.

--
From KT24 - in "Leafy Surrey"

Using a RISC OS computer running v5.11

"Man at B&Q" wrote in message
...
On Feb 7, 11:20 pm, "John" wrote:
"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.

Which group?

This one of course!



MBQ

"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.

Oh dear, my brain, such as it is, substituted the 'l' for an 'n'!

alan holmes wrote:
"Man at B&Q" wrote in message
...
On Feb 7, 11:20 pm, "John" wrote:
"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.

Which group?

This one of course!



MBQ

Which one? This thread is crossposted.

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?


NT

Well I finally got a few minutes to spare and made one. Didnt have
time to measure an existing one, so just vaguely guessed. It works,
albeit rather badly. Picture is quite a lot better than it was with
no
gain though, so there must be a handful of dB there. Unfortunately
me camera's broke though.


NT

wrote:
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?


NT

Well I finally got a few minutes to spare and made one. Didnt have
time to measure an existing one, so just vaguely guessed. It works,
albeit rather badly. Picture is quite a lot better than it was with
no
gain though, so there must be a handful of dB there. Unfortunately
me camera's broke though.

A Yagi design isn't the best basis for a home made aerial, particularly if
it's to be used indoors. The bi-square is a lot better for analogue and the
bow-tie plus grid-reflector seems to be very popular for digital.

(kim)