How to Dry Out Wet Coax?

[KA5UTN]

Yes, I screwed up. I failed to waterproof the connections from my LMR400 coax to the remote antenna tuner and BALUN connections. The weather was nice, but I forgot about my sprinkler system. So now I need a way to dry out the coax. I am able to bring all of it inside the house, so that helps.

Despite bad propagation, I was getting some good reception from my 24 ft flagpole OCF vertical dipole antenna. This morning the reception is terrible and I think water got into the coax connections. Please advise.

 

[KevinC]

Yes, I screwed up. I failed to waterproof the connections from my LMR400 coax to the remote antenna tuner and BALUN connections. The weather was nice, but I forgot about my sprinkler system. So now I need a way to dry out the coax. I am able to bring all of it inside the house, so that helps.

Despite bad propagation, I was getting some good reception from my 24 ft flagpole OCF vertical dipole antenna. This morning the reception is terrible and I think water got into the coax connections. Please advise.

You don't dry out coax, you replace it.

 

[kc2asb]

You don't dry out coax, you replace it.

Yep. Consider it a learning experience.

 

[prcguy]

Once the innards are wet it will corrode, time to replace.

 

[trentbob]

It's really not that unusual that coax gets water damage over a periods of time, I know there's much better methods now but I am a dinosaur but I've always insulated my connections with coax seal, first I wrap in electrical tape before applying the sealant with good coverage, that way if you want to remove the sealant you only need to remove the tape.

It is inevitable as time passes that coax can crack and develop leaks in various places.

 

[UTE-GE]

Considering cost of LMR400 assuming you bought the "top shelf". You might look into DRF-400 by Davis RF.
I have a run of about 75' of Bury Flex that's been very good.
Also bought a spool of RG-8, their brand and it's very nice.

​

 

[popnokick]

There is a large receptacle with a lid, usually green in color. The coax should fit in there.

 

[ladn]

You don't dry out coax, you replace it.

What about putting it in a large box and covering it with (dry) rice and sticking it in a warm oven?

 

[tlemke940]

if you can do the connectors yourself cut the end off that you think is wet down to where it is no longer wet or damaged and put a new connector on. when you do that you are cutting the damaged part off and starting with good feed line. the feed line its self should be able to handle being in a damp location as long as the jacket is intact.

 

[cg]

Transmit with 1000 watts for an hour or so, that should take care of it.

 

[kc2asb]

Transmit with 1000 watts for an hour or so, that should take care of it.

Take care of the radio you mean, right? (not sure why I channeled Yoda here)

 

[trentbob]

What about putting it in a large box and covering it with (dry) rice and sticking it in a warm oven?

Wouldn't a microwave oven work better Roger? Gives new meaning to the term "Sparky"

 

[mmckenna]

Yes, I screwed up. I failed to waterproof the connections from my LMR400 coax to the remote antenna tuner and BALUN connections. The weather was nice, but I forgot about my sprinkler system. So now I need a way to dry out the coax. I am able to bring all of it inside the house, so that helps.

The water is going to wick up the small voids between the aluminum shield foil and copper shield strands. It would be guess work to figure out how far it traveled down the cable. You could start chopping off pieces hoping you found where it stopped, but again, that would be a guess at best.

The dissimilar metals plus moisture is going to make a mess if any is left behind. You might get lucky, you might not. If you've got some slack in the cable, you could try and just watch your SWR/performance to see if it starts to degrade again.

If it was me, it would be 'lesson learned' and order a new length of coaxial cable and appropriate waterproofing kits.

At work, I'd never trust that coax again, and it would get replaced with all new.

Make sure you check the connectors for the ATU, as they may have gathered some moisture as well.

 

[k8niv]

Been there, done that...also had water in some RG 213 coax been using for years, had a bad pl connector, that was when I discovered water been inside it.....60ft roll lost..

 

[rgchristy]

As Rich @N9JIG suggested, maybe he should have rotated the coax...

Rotating your coax: A guide for newbies

Everyone knows that the coax is the most important part of a scanner antenna system. What many people forget is that, like the tires on your car, you need to rotate the coax from time to time. Spring is the optimum time to rotate the coax for most people, when it is warmer than winter and not...

forums.radioreference.com

Sorry, I couldn't help myself...That thread never gets old...Sometimes we have to laugh, because it beats crying...

 

[K5MPH]

If you are not getting good Rx like before did you even check the SWR to see what they are that may of told you that you may have a short ...

 

[rf_patriot200]

What about putting it in a large box and covering it with (dry) rice and sticking it in a warm oven?

That could be a Stinky proposition !!

 

[bharvey2]

What about putting it in a large box and covering it with (dry) rice and sticking it in a warm oven?

Well, sounds like a "recipe" for failure if you ask me.

On the other hand, I wouldn't blame someone for trying to cut off a few feet from the compromised end and hope for the best in a non-mission critical scenario. It's a roll of the dice for sure. If it was work related or even transmitting on my own equipment, I'd just tuck my tail and replace it, being sure to terminate it properly at the start. - No waiting to seal it up properly.

 

[ecps92]

That could be a Stinky proposition !!

and sticky as it melts

 

[prcguy]

The ends of the coax are for sure going to cause problems, question is how far up the cable did the water get? You can cut it back and maybe see but in my opinion its not worth perusing unless you want a lifetime of potential problems. If you want to install it just to look pretty then have at it. If you want to put it in service for actual use then expect problems. Two choices, pick one and don't complain if you pick the wrong one. If you think a number of people agreeing its good to use it will make it ok, it wont. Sorry you made a mistake but time to move on.

Edit:
Just two weeks ago I was helping a company sweep waveguide and cables in a new satellite installation. Sweeping cables showed a problem at 1.6GHz in all the 1/2" heliax runs, every one of the long runs. After some testing they found a particular spool of hardline had a problem with every cable so it all had to come out and was trash, many runs of $3.50/foot coax and $30 connectors not to mention labor pulling them underground and installing connectors with a crew that probably makes $75/hr each. Oh well, not fun but sometimes stuff happens. Be thankful its only LMR400.