"Harry H" wrote in
:

Some time ago I wrote to Hygain:

Sir,
Our Ham Radio Club owns 2 Hygain 18-AVT vertical antennas.
We are after 2 sets of black plastic shields which fit between the
vertical alloy tubing and the outer cover of the traps,
Can you supply them to us?

Harry



Hygain wrote back:

Sir,
The only parts available are tubing pieces.
Thanks,
Jim Shurden
Hygain Customer Service

Question is, what can I use as a substitute, I have tried truck wheel
cylinder boots, but the carbon in them upsets the apple cart.


Harry,

I had a 4BTV that suffered failure of the trap covers, a result of
destructive birds eating them.

I made replacement parts from PVC plumbing fittings, not because Hustler
couldn't supply parts, but there was little point repairing with same
fodder for the birds.

The repair is described at http://www.vk1od.net/H4BTV/hustler4btv.htm .
It might give you some ideas.

BTW, Hustler must have seen the article and sent me gratis a set of
original trap covers, they are still in the shed after twenty years...
the PVC works fine and the birds haven't attacked them (though they seem
to enjoy anthing else with exposed PE or vinyl).

Owen

"Owen Duffy" wrote in message
...
"Harry H" wrote in
:

Some time ago I wrote to Hygain:

Sir,
Our Ham Radio Club owns 2 Hygain 18-AVT vertical antennas.
We are after 2 sets of black plastic shields which fit between the
vertical alloy tubing and the outer cover of the traps,
Can you supply them to us?

Harry



Hygain wrote back:

Sir,
The only parts available are tubing pieces.
Thanks,
Jim Shurden
Hygain Customer Service

Question is, what can I use as a substitute, I have tried truck wheel
cylinder boots, but the carbon in them upsets the apple cart.


Harry,

I had a 4BTV that suffered failure of the trap covers, a result of
destructive birds eating them.

I made replacement parts from PVC plumbing fittings, not because Hustler
couldn't supply parts, but there was little point repairing with same
fodder for the birds.

The repair is described at http://www.vk1od.net/H4BTV/hustler4btv.htm .
It might give you some ideas.

BTW, Hustler must have seen the article and sent me gratis a set of
original trap covers, they are still in the shed after twenty years...
the PVC works fine and the birds haven't attacked them (though they seem
to enjoy anthing else with exposed PE or vinyl).

Owen


Thanks Owen,
I guess it was either the Galahs or the White Cockatoos that did the damage.

I know when I used to sell UHF CB to farmers out west, we used to have
trouble with them chewing on the top of the collinear antenna.

We used to slide some white PVC down over the vertical and anything over 3/4
to 7/8" in dia used to stop them.

It annoys me that Hygain will not supply them and must get a high enquiry
rate for these shields.

I will see if I can find the right diameter and machine them to fit snugly.

Thanks for the heads up on your experience!

Thanks to all those who have offered their advice too.

73
Harry

"Harry H" wrote in
:

....
Thanks Owen,
I guess it was either the Galahs or the White Cockatoos that did the
damage.

Sulphur Crested Cockatoos!

Still, I have sympathy for the ZLs where Keas eat the rubber seals out of
car windows.


I know when I used to sell UHF CB to farmers out west, we used to have
trouble with them chewing on the top of the collinear antenna.

We used to slide some white PVC down over the vertical and anything
over 3/4 to 7/8" in dia used to stop them.

Yes, I have built radomes from white PVC plumbing fittings to protect
antennas, eg MobileOne's 2m end fed which has a balun made from coax
wound around the outside of the antenna... good tucker for birs.

It annoys me that Hygain will not supply them and must get a high
enquiry rate for these shields.

I have had experience with Hy-Gain, and it was very poor... wound up
making the parts myself... http://www.vk1od.net/VB214/index.htm .

Mindful of that, I limit my exposure to products of the MFJ group.


I will see if I can find the right diameter and machine them to fit
snugly.

I am sure you will come up with a working solution, and possibly a better
one.


Owen

Dear Owen:

Experience here in the Upper Midwest is that ground dwelling animals will
chew PVC. but not PE. Had to replace a vast amount of PVC covered cable,
but PE covered coax and cable was untouched.

What have others found? 73, Mac N8TT

--
J. McLaughlin; Michigan, USA
Home:
"Owen Duffy" wrote in message
...


snip

I made replacement parts from PVC plumbing fittings, not because Hustler
couldn't supply parts, but there was little point repairing with same
fodder for the birds.

The repair is described at http://www.vk1od.net/H4BTV/hustler4btv.htm .
It might give you some ideas.

BTW, Hustler must have seen the article and sent me gratis a set of
original trap covers, they are still in the shed after twenty years...
the PVC works fine and the birds haven't attacked them (though they seem
to enjoy anything else with exposed PE or vinyl).

Owen

"J. Mc Laughlin" wrote in
:

Dear Owen:

Experience here in the Upper Midwest is that ground dwelling animals
will chew PVC. but not PE. Had to replace a vast amount of PVC
covered cable, but PE covered coax and cable was untouched.

Hi Mac,

I know that some animals (eg rats) will eat soft PVC. That motivates cable
sheaths impregnated with arsenic... which is worse? We don't have some of
the critters that you have, thankfully.

The other commonly used plastic I didn't mention was polypropylene, and I
think the trap covers may be polyprop... .

All in all, vermin resistance components, and ready availability are
important factors in the life of antennas etc... but we are tame buyers who
generally don't consider that until we need to repair the things.

Owen

Dear Owen: I just realized that I sent you a message but it will not
arrive for you do not use a real E-mail address.

73, Mac N8TT

--
J. McLaughlin; Michigan, USA
Home:
"Owen Duffy" wrote in message
...
"J. Mc Laughlin" wrote in
:

Dear Owen:

Experience here in the Upper Midwest is that ground dwelling animals
will chew PVC. but not PE. Had to replace a vast amount of PVC
covered cable, but PE covered coax and cable was untouched.

Hi Mac,

I know that some animals (eg rats) will eat soft PVC. That motivates cable
sheaths impregnated with arsenic... which is worse? We don't have some of
the critters that you have, thankfully.

The other commonly used plastic I didn't mention was polypropylene, and I
think the trap covers may be polyprop... .

All in all, vermin resistance components, and ready availability are
important factors in the life of antennas etc... but we are tame buyers
who
generally don't consider that until we need to repair the things.

Owen