[TowerTalk] Fwd: Protecting Aluminum Antennas

[George Dubovsky]

On Sat, Mar 19, 2016 at 11:53 AM, David Gilbert <xdavid at cis-broadband.com>
wrote:

>
> I'm not advocating anodizing antenna elements, only disputing that it
> makes any difference electrically,


​Of course it makes a difference electrically; otherwise, why would you
have to remove it? Properly done, it's more than just a few microns in
depth, it's a mil or more, depending on the current used in the process and
the length of the process. So by the time you remove it, you've done
significant dimensional damage to the element​. That's assuming you anodize
only the outside of the tubing, and it costs a lot to protect one surface
of the product from the acid. So now you've got twice the amount of
material removed in the joint.

And anodizing doesn't impart any color to the aluminum; it's clear to
perhaps very, very light beige on some alloys. The die is added afterwards
for cosmetic effect.

Now, alodine (a chromate conversion) has been used on tv antennas back in
the day; it's conductive.

Anybody not capable of abrading the anodizing at the joints shouldn't be
> putting up antennas anyway.
>

​Really? Really?

73,

geo - n4ua
​


>
> Dave   AB7E
>
>
> On 3/19/2016 12:37 AM, J Chaloupka via TowerTalk wrote:
>
>> Anodize is an insulating surface coating.  Take it from there on what
>> that means to joing the elements of an array electrically.JIM W4QBQ
>>
>>        From: David Gilbert <xdavid at cis-broadband.com>
>>   To: Jim Miller <jtmiller47 at gmail.com>; Larry Loen <lwloen at gmail.com>
>> Cc: TowerTalk <towertalk at contesting.com>
>>   Sent: Saturday, March 19, 2016 1:06 AM
>>   Subject: Re: [TowerTalk] Protecting Aluminum Antennas
>>
>> That's not true at all.  Anodizing merely adds a dye to a very thin
>> surface oxide.    Aluminum oxide is going to grow naturally anyway, and
>> is essentially an insulator.  Skin effect doesn't apply to a surface
>> insulator.
>>
>> Dave  AB7E
>>
>>
>>
>> On 3/18/2016 8:07 PM, Jim Miller wrote:
>>
>>> Electrical resistance
>>>
>>> On Mar 18, 2016, at 10:47 PM, Larry Loen <lwloen at gmail.com> wrote:
>>>
>>> Yes, I have often wondered why annodized aluminum couldn't be used.  I
>>> assume there is a reason.  But it would sure help make antennas less
>>> conspiculous.
>>>
>>>
>>> WO7R
>>>
>>> On Fri, Mar 18, 2016 at 5:03 PM, David Gilbert <xdavid at cis-broadband.com
>>> >_______________________________________________
>>>
>>>>
>>>>
>>>> t <http://lists.contesting.com/mailman/listinfo/towertalk>
>>>>
>>>