FlightAware Discussions

Sudden Loss of range

I was coming here to start thread on loss of range. I went from an average track of about 180 nm to just about 55 nm.

I read a comment about water and another gentleman who said his range was indeed affected by water intrusion at the antenna. I pulled my antenna apart and sure as crap water in the connection.

I used a few q-tips some rubbing alcohol and compressed air to clean them out and the range went back to normal.

Thanks for the postings.
Tim

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Thanks for checking the forum before you posted, not everybody does that…:+1:

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Put some silicon grease inside any outside connectors. It won’t affect the connection, but it will keep water out and inhibit corrosion.

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Thanks!

I went back up and added some dielectic grease.

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I wonder: will WD-40 do too? For example at the coax connector of the FA antenna.

Update: possibly not: https://www.eham.net/ehamforum/smf/index.php/topic,39094.msg256691.html#msg256691 (bottom comment).

I wouldn’t use mineral oil based products or greases.

The big plus of silicon oil / grease is that it won’t degrade plastics.

Possibly the most misused substance on the planet. WD-40 is a water dispersant and cleaning solvent, but it’s not persistent enough to provide long term protection. It can be used to get rid of water that already there, but as wiedehopf says mineral oils often attack plastics. With coax it could wick up inside and damage the dielectric foam or core.

Silicone or dielectric grease won’t cause damage to plastics, and it won’t affect the impedance of the connection.

You could do it the fisherman’s way and wrap everything in denso tape, but I wouldn’t recommend it. It would be waterproof but cleaning it of again isn’t much fun.

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Try the following:

“Wrap once with self amalgamating tape (Scotch 2242 or 3M 2155 Temflex, available at home stores) and follow this with a layer of Scotch 33+. The 33+ is required to achieve UV resistance. This combination cuts apart cleanly if needed for maintenance.”

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I use
" Proxicast Pro-Grade Extra Strong 30mil Weatherproof Self-Fusing Silicone Sealing Tape For Coax"

You can read about it here, and get it on Amazon as well:
http://shop.proxicast.com/shopping/proxicast-pro-grade-extra-strong-weatherproof-self-bonding-non-adhesive-30mil-silicone-sealing-tape-1.5-x-15-roll-black.html

Has held up well for years, easy to cut off and re-apply when re-doing cabling, antennas, etc.

Direct burial cable is often “jelly filled” - the ‘jelly’ being petrolium jelly, sold retail as vaseline.

I’m not suggesting anyone goes out and prices this stuff, but working backwards through the datasheets, it’s easy to work out the materials not affected by mineral oils.
(PVC, Polyethylene and Polyester in the example above).

Hmm. I wouldn’t be sure that PE foam is not affected by mineral oil.

Anyway you are correct, it’s most likely better to smear it with grease than having water ingress :slight_smile:

I think I’ll stick with the self amalgamating tape!

If you don’t cover it with PVC tape, it will disintegrate from the UV.

I’ve used several (quality) brands of self amalgamating tape for many years without additional protection.
So far, none have shown any sign of deterioration.

Of the two tapes suggested above (@Dxista), the Scotch 2242 tape claims UV stability, while the Temflex 2155 does not.

Chose your tape wisely!

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The UV resistance is given by the Scotch 33+ tape. So you wrap the connection twice, the first with either the 2242 or 2155 followed by another wrap with Scotch 33+.

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It’s interesting - the datasheet for Scotch 33+ only comment on the subject is:

It has excellent resistance to abrasion, moisture, alkalies, acids, corrosion and varying weather conditions (including ultraviolet exposure).

Where as Scotch 2242 quotes the test regime it complies with (ASTM D–4388).

fixed the second link

I concur, on Scotch 2242.
The Proxicast tape I listed also meets ASTM D–4388.
Scrotch 33+ meets UL 510 which is a similar UV rating, so not much benefit, over just using 2242 or the Proxicast Pro grade by themselves.

(Found via https://multimedia.3m.com/mws/media/104792O/scotch-super-33-vinyl-electrical-tape-pdf-27-3kb.pdf and http://psatape.com.tw/ul/ul510.pdf)

Temflex 2155 is not UV resistant, so would need an additional coating, so might as well skip it for one of the others.

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