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[TowerTalk] TA-33 restoration

To: <towertalk@contesting.com>
Subject: [TowerTalk] TA-33 restoration
From: K2JAS@worldnet.att.net (Roger L. Elowitz)
Date: Mon, 28 Jul 1997 23:38:04 -0400
Hi Al,

I completely refurbished a TA-33 last fall. It looks and works beautifully.
Here are a few things you can do to make yours look and work like new too.

1. Write to Mosley at:

                                      Mosley Electronics, Inc.
                                      10812 Ambassador Blvd.,
                                       St. Louis, MO 63132
                                       Orders: 1 800-325-4016 or 1
800-966-7539

Ask them to send you the parts price list along with the assembly "manual."
 They will be glad to do so. I mention this so that if you should run
across parts that need replacing you can order them immediately. Their
order department will handle your order most expeditiously. I do not work
for the company nor am I in any way connected to their business. I also do
not work for 3M or Krylon.  In fact, I am fully retired and refuse to work
for anyone.

2. With the instructions in hand it will be very easy to completely
disassemble the 
    entire beam and put it back together making sure that the traps are
facing in the 
    correct directions and installed on the correct elements. We are NOT
talking about 
    rocket science here. The most you're going to need is a screwdriver and
perhaps a 
    socket wrench.

3. I would remove the sheet metal screws that hold the elements together
and    
    carefully clean the ends of the tubes where they mate. I use
Scotchbrite abrasive 
    pads. Before reassembling the tubes I would coat the mating surfaces
with an 
    antioxidant conductive grease. You can order Mosley's Penetrox to do
that job.  It's 
    dirty and I will guarantee it will get your clothes filthy. Be prepared.

4.  Disassemble the traps making absolutely sure you mark which end goes back 
     which way.  Reversing things here is a big NO NO.  Use masking tape
and a 
     marking pen to label things and work slowly and carefully. Again, this
is not rocket 
     science.  Just be reasonably careful.

5.  With the covers off the traps, inspect the coil forms for cracks. I
would replace any 
     coil with a cracked form.  You can order each coil separately. The
older TA-33's  
     had their coil ends secured with sheet metal screws that will
eventually loosen.  
     Remove the screws and scrape the wire clean and reinstall the sheet
metal screw.   
     If it strips... get the next larger size stainless steel sheet metal
screw.  Clean out 
     any spider webs.

6.  When you reassemble the traps, scrape the outside of the can clean
under the wire 
     and scrape the wire clean too before you secure it with its sheet
metal screw. 
     Make absolutely certain that the condensation drip holes end up on the
underside 
     of the beam (facing downward) because the last thing in the world you
want is 
     traps full of water.  Mark my words... IT HAS HAPPENED!

7.  I have been advised to insert wooden dowels loosely in the end tubes
from the 
     traps toward the tip of the elements.  The dowels (which I sprayed
liberally with 
     Krylon Crystal Clear lacquer) are only there for vibration dampening.
You can  
     accomplish the same dampening by getting some clothesline rope to lay
loose in 
     the element tip.  Again, we're not talking rocket science here.

8.  I replaced all the phospher-bronze star washers wherever you find them.

9.  I also found some of the black driven element insulator blocks cracked. 
     Replace those too.

10.  I particularly disliked the way Mosley connects the coax to the driven
element.  
       I believe that the screws that hold the elements to the insulators
also hold the  
       coax.  This means that when you unscrew your coax ...your elements are 
        dangerously supported in one place.  Either you must securely tape
the element 
        in place or better yet, do as I did.... drill separate holes to
attach the coax.  I 
        used stainless screws in the new holes and also small pieces of
stainless or 
        aluminum tubing inside the element ends that the screws go through
to keep the 
        screws from squeezing the element out of shape.

11.  Finally, with the coax attached, it behooves you to devise a way to
keep water 
       from entering the coax.  THIS IS CRITICAL.  Use Scotch 33 or 88 tape
and 
       carefully do a spiral wrap from the antenna attachment lugs to the
point where the 
       coax braid is separated from the center conductor.  Do NOT pull the
tape tightly
        for the last turn of the wrap.  Then coat the tape and the
attaching screws with 
        a sticky waterproof coating of Scotchkote.  DO NOT BREATH ITS FUMES
IN A 
       CLOSED- NON-VENTILATED LOCATION. To do so will instantly cause your  
        brain to be higher that any antenna you can ever
erect....permanantly.  

12.  And now for the final trick.  I bring my coax off the driven element
in an upward 
       spiraling loop making it IMPOSSIBLE  for water to run down, INTO the
coax, if, 
       heaven forbid, you neglected to perfectly seal it properly. DO NOT
bother using a   
       balun of any kind.  Mosley doesn't recommend it and neither do I.

That's basically all there is to it.  If you are as completely nutsy as I
am... and you have absolutely nothing better to do with your free time... I
would recommend that you take your Scotchbrite abrasive pads and shine
those dull elements until it hurts to look at them in the sunlight.  Then
give all the aluminum two and possible three coats of Krylon lacquer.  

Absolutely DO NOT DO THIS TO ANY ANTENNA YOU DO NOT PERSONALLY OWN. It is
so much work... the labor you have invested here far, far outweighs the
cost of a brand new beam... IF your time is worth anything!!!  I bought my
beam for $75 and I must have put $500 worth of labor and $50 in sundry
parts and stuff into it.  As I said..  one does NOT restore an antenna like
this to save money IF YOUR TIME IS WORTH ANYTHING!  

Of course you can totally skip the shining and lacquering part and see
absolutely not one iota difference in performance and consequently save a
tremendous amount of labor in the process.  But then, the antenna won't
glint in the sunlight nor will it make the JA's and ZK's run screaming from
their homes with their clothes on fire when they tune you in.

Good luck with your restoration project and of course....have fun.

Roger, K2JAS

s¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤øø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø¤º°`°º¤ø,¸¸

> PM 7/28/97 +0000, you wrote:
>I've been given on "perminant loan" a Mosley TA-33 tribander.  It is 
>supposedly in working condition, but some of the bolts, saddles, etc 
>look very corroded (they are workable).  Any hints/kinks for 
>refurbushing this antenna?  Thanks.
>-- 
>Al, KE1FO, ex. KE6BER    mailto:ke1fo@contesting.com or ke6ber@tiac.net
>Check out my web page, http://www.tiac.net/users/ke6ber for summaries 
>from the contest reflector and a growing list of amateur radio links.
>
>--
>FAQ on WWW:               http://www.contesting.com/towertalkfaq.html
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>

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