[600MRG] Trap-Loaded antennas

[Kenneth G. Gordon]

On 15 Sep 2015 at 16:15, dick.bingham wrote:

> Hello again Ken

Hello, Dick. :-)

> OK ON ALL . . .

Good.
 
> My reference to #1, #2, #3 and #4 wire ends was not related to the numbers in
> the articles, just a means to try to put identifiers on the beginning and
> end of each winding.b 

Oh. I have not read the article again, so I was off, but even so, you got the idea OK.

> Also w/r/t ===> "Also, the great care to wrap with tape or apply shrink-fit
> tubing over the resonator seem like a total waste. The inner part of the traps
> where the wires penetrate the coil-form appear not to be protected from
> moisture. I can envision lots of moisture being sucked into the sealed air
> space under the tape or shrink-tube thru those pass-thru holes. 

That may be, 
 
> Well, yes, but the reason for the shrink-wrap is to prevent the windings from
> forcing themselves apart. The windings must be very tight to control the
> capacitance. 
> 
> The insulation will have no holes in it if done correctly, so moisture
> will not
> effect (affect !) it."

I have NEVER been able to get "affect" and "effect" correct. Drives me nuts.

> ================== I still have concerns about moisture getting inside the
> shrink-tube or tape cover. There is no reference to making an effort to seal
> the holes thru which the wire passes thru the coil form. Having a build-up of
> water in amongst the turns would, I believe, change the dielectric
> environment inside the covered trap and possibly modify the trap resonant
> frequency. 

Well, I don't think that is going to bother the traps at all. The spaces between turns are very, 
very small, and I doubt there would be much ingress of water.

> Is this a valid concern ?

I don't think so, but, believe me, I am most certainly no expert on this either.

I think we are going to have to try it out and see what happens.

I sure intend to do so, at any rate.

vy 73, and thanks for the input.

I plan to begin building the traps next week.

Ken W7EKB