Old coax, clean up?

[UlteriorModem]

I'm working on a home brew Yagi for the aviation band. I will post on that in another thread when it gets done.

But I had some old RG8X around that I decided to use.

When I stripped it down and started un-braiding the shield it was kind of discolored, brown, and had a gummy tacky feel to it!

This was way down from the end in the 'middle' of the run. But I have come across this before with all kinds of coax.

Questions are..

How does this happen? It's been stored rolled up indoors for years.

How best to clean it up to where it will accept solder?

ps; the center conductor was discolored as well ?

 

[trentbob]

Depending on the quality of the coax when it gets old it deteriorates. Your coaxial is very important to your setup so why even bother fooling with this stuff

You didn't say how long of a run it is but personally I would just ditch it. It's not like you are going to use it for the 7- 800 megahertz range but still... probably brittle and might be very compromised at some point along the line. Just my two cents.

 

[KevinC]

The best way I've found to clean up coax like that is to take it outside and put it in the trash.

 

[cmdrwill]

OLD coax OFF to the TRASH......

You will not get the corrosion off the shield.

 

[mmckenna]

How best to clean it up to where it will accept solder?

ps; the center conductor was discolored as well ?

Yeah, don't waste your time on this. If it's oxidized or suffered from water intrusion, then it's going to be an ongoing issue and you'll end up replacing it anyway. Might as well start with new/good stuff and save yourself all that hassle and headache.

If you really wanted to, just for giggles, you'd probably want to polish/sand the oxidization off, then use some solder flux, then solder it.

But then you still have all that oxidized copper, probably broken down dielectric, probably broken down jacket. Seems like sort of a waste of time if you are trying to build a new antenna. You're setting yourself up for failure even before you get the thing up in the air.

 

[UlteriorModem]

I ended up cleaning it with some acetone, sand paper, and scraping it with a knife edge.

As far as 'throwing it out' I dont think the coax is really degraded and some minor oxidation on the conductors should not be too detrimental. It is only about a 20' run, will not be used for transmitting, receive only. And is a test setup for the Yagi i am working on. If it works well i might put some 'new' coax on it.

After the clean up it did take some electronic solder without having to add any flux.

 

[mmckenna]

Good deal.

Just remember, if the copper was oxidized, it's likely the jacket is compromised. If it starts acting up, it's likely water found it's way inside.

 

[trentbob]

I ended up cleaning it with some acetone, sand paper, and scraping it with a knife edge.

As far as 'throwing it out' I dont think the coax is really degraded and some minor oxidation on the conductors should not be too detrimental. It is only about a 20' run, will not be used for transmitting, receive only. And is a test setup for the Yagi i am working on. If it works well i might put some 'new' coax on it.

After the clean up it did take some electronic solder without having to add any flux.

My only question would be is, being the compulsive, detail oriented type that I am, especially if I'm going to all the trouble of making a homemade antenna... How are you going to know if your homemade antenna worked? No need to answer, a rhetorical question.