Running a tracker ant thru metal washer?

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fyrwrxz

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Okay- newb question here. For reasons only known to the rocket gods and this poor sod, I need to run a ComSpec antennae (ch 345) thru a metal washer about 25% down the length. Will this act as a ground plane or just interfere with the signal? IDK-but it's flying in two days. We have a little more wind than normal, so I'm stepping down in motor, but it's a performance bird, so the feathers need the speed. Hence the tracker. Bad idea? Just tape it to the Kevlar?
 
Not a problem as long as the washer is not connected to the tracker ground.
 
The washer will act as an RF choke of sorts, attenuating the signal. It will likely also detune the antenna. Not a good idea.

Gerald
 
It will likely also detune the antenna. Not a good idea.

That assumes the antenna was in tune to begin with. The washer may actually "tune it".

Very easy to test. Setup tracker without antenna going through washer. Turn-on. Walk a some distance away with your Handheld with no antenna connected. Read the s-meter versus distance.

Put the antenna through the washer. Repeat. Compare s-meter readings. Each s-unit is about 6db.

Please post the results!
 
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Good input guys! Thanks- I was worried about the 'choke effect' so I'll ground test on the range tomorrow. Prolly post Sunday.
 
Good input guys! Thanks- I was worried about the 'choke effect' so I'll ground test on the range tomorrow. Prolly post Sunday.

My bet is that you won't be able to tell the difference.
 
I dont think it will have any effect at all.. it may act slightly as a ferrite ring/choke but I think you'll find there isnt enough washer to do crap all. Happen to have a VSWR meter or spectrum analyser with tracking gen and a directional coupler? :D

All in all, gut feel for me is about a 0.3db loss at most.
 
I dont think it will have any effect at all.. it may act slightly as a ferrite ring/choke but I think you'll find there isnt enough washer to do crap all. Happen to have a VSWR meter or spectrum analyser with tracking gen and a directional coupler? :D

All in all, gut feel for me is about a 0.3db loss at most.
Well folks the results are in. Sorry no pics until I can find my darn cameras ( I lose everything from time to time-common sense, financial responsibility and any self control concerning rocket parts are those I miss the most). lacking way cool stuff to scientifically verify the results, I set up my cheesy little tracker about 200' away about 10' off the ground. Initial readings were good (like, it still works!) and then washers were added up to about 3/4" thick-no discernible change. I took a few pieces of hardware out of the range box, like brass threaded inserts, aluminium sled guides, ss nuts and stacked them half way up the ant and, viola! No change! Of course, I was only out a little ways, but the walks back and forth were a little wearing so I gave it up as a good deal done. Thanks for input, gents, and see you out on the field.
 
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