[OZAPRS] Stupid question - keeping foldable antenna base clean?

Ray Wells vk2tv at exemail.com.au
Mon Aug 6 11:45:51 EST 2007


Damien Gardner Jnr wrote:

>So I think I've figured out why my D7 quite often goes quite deaf (i.e.
>I can 'hear' the digis repeating my posits as I drive from dandenong to
>frankston, but the D7 doesn't decode them).. - the antenna I have on it
>is a rather tall 2m/70cm dualbander that I bought from Andrews comms.. -
>it's made of lengths of stainless steel (?) with joiners (chokes?) at
>certain points up the length..  The base screws straight onto a PL259
>(dear god did that confuse me when I got it!), and at the top of the
>base, the antenna itself has a conical shaped bottom, which is held into
>an equally conical 'socket' by a spring - idea being that you can lift
>the antenna up, and fold it back (which I have to do every time I take
>dad to the hospital, or go into the city - what is it with 2.4m
>clearances?!?!?!).  The problem with this design, is that a) wind coming
>past the antenna tends to put enough force on it to lift it up a bit
>(Heading north up the hume will ALWAYS produce enough wind to have it
>lift up out of its socket and lay down on the bonnet.. - never does it
>coming south!), and make it wave around, and b) because of that, water
>gets in and it corrodes something horrid..
>
> 
>
>I gave it a damned good clean while cleaning the hilux the other day
>(first time it's had a wash in the 18 months I've owned it ;) ), and all
>of a sudden, the D7 has stopped being so 'deaf'..
>
> 
>
>Anyone else have one of these antennas and have a fix for this
>'problem'?  I would just fibreglass or epoxy it fixed in place, but
>because of the length of it, i need to be able to lay it down a couple
>of times a week..  But I figure that I can't be the only one who has
>this kind of problem with one of these antennas??
>
> 
>
>Cheers,
>
>
>Damien
>
> 
>
>--
>
>Damien Gardner Jnr
>
>VK2TDG/VK2DGJ. Dip EE. StudIEAust
>
>Home: rendrag at rendrag.net -  http://www.rendrag.net/
>
>Play: vk2tdg at pinegap.net  -  http://pinegap.net/
>
>--
>
>We rode on the winds of the rising storm,
>
>  We ran to the sounds of thunder.
>
>We danced among the lightning bolts,
>
>  and tore the world asunder
>
> 
>
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>
There used to be a "knock-down" adaptor available for commercial mobile 
whips (70-85 and 148-174MHz). One made by AWA (yes, I am going back a 
looong time) comes to mind. The arrangement had a spring loaded ball 
that rested in a vee when the antenna was upright.

Those adaptors were notorious for going open circuit on receive, from an 
oxide film that coated the metal parts. A quick burst of PTT was enough 
to break down the oxide ......... for a while.

Ray vk2tv
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