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Off-Topic - Antenna element repairs

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ae4pb

Off-Topic - Antenna element repairs

I have a vertical antenna to repair and install that I believe is the same
as or close to a hi-gain AV-18HT.
https://www.hy-gain.com/Product.php?productid=AV-18HT.
The main antenna vertical was cut so it could be taken down. I purchased it
used in hopes I could repair and install it.
I have two different places that require repair. Purchasing new parts for
the element appear to approach the cost of an entirely new antenna.
I'm thinking of three different methods of repair but lack experience.
1. I can braze the elements using aluminum brazing rods and flux.
2. I can get them welded back together but am concerned that the tubing is
very thin.
3. I can try to find tubing of sufficient size to put inside and then
pop-rivet/braze the pieces together.

What do you folks suggest?

Thanks in advance. I've collected about a fourth of the wire necessary for
the radials.

Jerry D. Moore
AE4PB

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k6dgw

Re: Off-Topic - Antenna element repairs

#3

73,
Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 3/15/2020 3:01 PM, [hidden email] wrote:

> I have a vertical antenna to repair and install that I believe is the same
> as or close to a hi-gain AV-18HT.
> https://www.hy-gain.com/Product.php?productid=AV-18HT.
> The main antenna vertical was cut so it could be taken down. I purchased it
> used in hopes I could repair and install it.
> I have two different places that require repair. Purchasing new parts for
> the element appear to approach the cost of an entirely new antenna.
> I'm thinking of three different methods of repair but lack experience.
> 1. I can braze the elements using aluminum brazing rods and flux.
> 2. I can get them welded back together but am concerned that the tubing is
> very thin.
> 3. I can try to find tubing of sufficient size to put inside and then
> pop-rivet/braze the pieces together.
>
> What do you folks suggest?
>
> Thanks in advance. I've collected about a fourth of the wire necessary for
> the radials.
>
> Jerry D. Moore
> AE4PB
>

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Elecraft mailing list

Re: Off-Topic - Antenna element repairs

DX Engineering probably has what you require for tubing repair. Given
that you are repairing from the inside a thicker wall would be useful,
easy with a length inside the first repair length.

Regards,

Mike VP8NO

On 16/03/2020 14:06, Fred Jensen wrote:

> #3
>
> 73,
> Fred ["Skip"] K6DGW
> Sparks NV DM09dn
> Washoe County
>
> On 3/15/2020 3:01 PM, [hidden email] wrote:
>> I have a vertical antenna to repair and install that I believe is the
>> same
>> as or close to a hi-gain AV-18HT.
>> https://www.hy-gain.com/Product.php?productid=AV-18HT.
>> The main antenna vertical was cut so it could be taken down. I
>> purchased it
>> used in hopes I could repair and install it.
>> I have two different places that require repair. Purchasing new parts for
>> the element appear to approach the cost of an entirely new antenna.
>> I'm thinking of three different methods of repair but lack experience.
>> 1. I can braze the elements using aluminum brazing rods and flux.
>> 2. I can get them welded back together but am concerned that the
>> tubing is
>> very thin.
>> 3. I can try to find tubing of sufficient size to put inside and then
>> pop-rivet/braze the pieces together.
>>
>> What do you folks suggest?
>>
>> Thanks in advance. I've collected about a fourth of the wire necessary
>> for
>> the radials.
>>
>> Jerry D. Moore
>> AE4PB

AI4NS

Re: Off-Topic - Antenna element repairs

Also Maxgain systems

On Mon, Mar 16, 2020 at 14:00 Mike Harris via Elecraft <
[hidden email]> wrote:

> DX Engineering probably has what you require for tubing repair. Given
> that you are repairing from the inside a thicker wall would be useful,
> easy with a length inside the first repair length.
>
> Regards,
>
> Mike VP8NO
>
> On 16/03/2020 14:06, Fred Jensen wrote:
> > #3
> >
> > 73,
> > Fred ["Skip"] K6DGW
> > Sparks NV DM09dn
> > Washoe County
> >
> > On 3/15/2020 3:01 PM, [hidden email] wrote:
> >> I have a vertical antenna to repair and install that I believe is the
> >> same
> >> as or close to a hi-gain AV-18HT.
> >> https://www.hy-gain.com/Product.php?productid=AV-18HT.
> >> The main antenna vertical was cut so it could be taken down. I
> >> purchased it
> >> used in hopes I could repair and install it.
> >> I have two different places that require repair. Purchasing new parts
> for
> >> the element appear to approach the cost of an entirely new antenna.
> >> I'm thinking of three different methods of repair but lack experience.
> >> 1. I can braze the elements using aluminum brazing rods and flux.
> >> 2. I can get them welded back together but am concerned that the
> >> tubing is
> >> very thin.
> >> 3. I can try to find tubing of sufficient size to put inside and then
> >> pop-rivet/braze the pieces together.
> >>
> >> What do you folks suggest?
> >>
> >> Thanks in advance. I've collected about a fourth of the wire necessary
> >> for
> >> the radials.
> >>
> This
>

Rick Bates, NK7I

Re: Off-Topic - Antenna element repairs

In reply to this post by k6dgw

If you can find a length of tubing one size larger (so that the pieces
to be repaired just barely fit inside); cut a length long enough to
provide lateral strength (side load), cut slits into the ends of the
patch lengthwise then overlay that to 'mend' the two pieces (make it
continuous again) and use worm gear clamps on the slits to bind it
together (making sure that the original two parts are close so you don't
have to trim to resonance).

The overlaid section will be stronger than the original (two layers) if
you do this correctly and have a long enough patch (which will depend on
the overall length since length gives leverage).

Some will suggest also adding conductive grease on the elements
overlapping. Other may also suggest adding two (at each end) small
bolts at 90 degrees to each other to back up or replace the clamps
(belts and suspender mode). I don't suggest bolts as they're hard to
realign next time and reduce the amount of material needed at the patch
(makes it weaker).

I've also (because it was available) taken fiberglass rod and put that
INSIDE the two aluminum ends, with bolts to keep it in place and a clamp
to span any distance between the ends. It worked but isn't as
electrically sound.

I would not use a pop rivet, it's not bonded hard enough to the elements
(you'd still need an overlaid section), isn't strong enough over time
and could create a weak enough contact point for RFI later. Brazing
also brings in a dissimilar metal and creates even more issues.

GL es 73,
Rick NK7I

On 3/16/2020 10:06 AM, Fred Jensen wrote:

> #3
>
> 73,
> Fred ["Skip"] K6DGW
> Sparks NV DM09dn
> Washoe County
>
> On 3/15/2020 3:01 PM, [hidden email] wrote:
>> I have a vertical antenna to repair and install that I believe is the
>> same
>> as or close to a hi-gain AV-18HT.
>> https://www.hy-gain.com/Product.php?productid=AV-18HT.
>> The main antenna vertical was cut so it could be taken down. I
>> purchased it
>> used in hopes I could repair and install it.
>> I have two different places that require repair. Purchasing new parts
>> for
>> the element appear to approach the cost of an entirely new antenna.
>> I'm thinking of three different methods of repair but lack experience.
>> 1. I can braze the elements using aluminum brazing rods and flux.
>> 2. I can get them welded back together but am concerned that the
>> tubing is
>> very thin.
>> 3. I can try to find tubing of sufficient size to put inside and then
>> pop-rivet/braze the pieces together.
>>
>> What do you folks suggest?
>>
>> Thanks in advance. I've collected about a fourth of the wire
>> necessary for
>> the radials.
>>
>> Jerry D. Moore
>> AE4PB
>>
>
> ______________________________________________________________
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