[ARC5] Ceramic Beads

[Michael Hanz]

On 5/24/2018 11:39 AM, Craig wrote:
> Thanks for the info Glenn. I'll have to drop them a note and check on 
> availability.
>
> Mike: I've got to have the W-106-A for this installation. The external 
> antenna is made out of it also. 

I believe you.  All I know is that comparing modern Copperweld to the 
W-106-A I have on reels, the only difference seems to be a .001" larger 
outside diameter on the modern stuff.

> I haven't found the drawings for it yet, but from the maintenance 
> books, it appears that there are no tension springs in the 
> installation. It looks like the antenna is fabricated to a specific 
> dimension and hard bolted between the fuselage and the vertical fins. 

That's interesting.  I can't recall ever seeing an aircraft antenna that 
did not have _some_ kind of tensioning unit on it.  The photo below 
seems to show a conventional ceramic insulator and a tension unit on 
each leg of the wire antenna.  It isn't only wind pressure that needs to 
be compensated - it's temperature expansion and fuselage flexing.  
Evidently even with a tensioner, the antennas broke fairly frequently.



> At 200 mph, I would be wary of an 18 ga. all copper antenna stretching 
> and sagging and then fluttering.

I would too, but that's not what I get from The Wireman.  If you went to 
the link I provided, you'll see Type 501 wire is 18 gauge Copperweld 
with a steel core.

His website says "18 AWG solid copper-clad steel (30%).  The most 
economical and versatile antenna wire.  Strong enough for any HF dipole 
(break strength 280 pounds) and as light and easy to use as stranded."

You'll note the breaking strength of this exceeds the 170 pound strength 
supplied by Standard Wire and Cable.

But you should do as you think best.  I'm just offering ideas for 
consideration.

Good luck,

-Mike  KC4TOS
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