| Author |
Message |
    
Kabar
Junior Member
Username: Kabar
Post Number: 26
Registered: 6-2003
| | Posted on Saturday, May 05, 2007 - 7:10 pm: | 
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How often should coax cable be replaced as a matter of maintenance? |
Bruce
Senior Member
Username: Bruce
Post Number: 4434
Registered: 9-2003
| | Posted on Saturday, May 05, 2007 - 8:07 pm: |
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when it gets damaged or hard ....
On 6 since 66
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Tech237
Moderator
Username: Tech237
Post Number: 767
Registered: 4-2004
| | Posted on Sunday, May 06, 2007 - 6:53 pm: |
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... or starts to look discoloured - that generally means water has got into it. I check my cable physically at least once a year. I keep a record also of the SWR and power loss on each cable at the time of installation and check against that. When it starts to show an appreciable change the coax is replaced no matter how old/new it is.
Simon
Tech237
KD7IEB
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Dale
Advanced Member
Username: Dale
Post Number: 844
Registered: 12-2002
| | Posted on Sunday, May 06, 2007 - 10:51 pm: |
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hey tech237 i got some old rg8 coax from a yard sale.the one end looks good but the other end looks like its been burnt.the outer jacket doesnt appear to be affected by this just the stranded conductor.i have no ohm meter or dmvm
either to chect continuety.no pls on either ends
do you think this coax is any good didnt notice the one end when i bought it.whats your opion?
dale/a.k.a.hotrod
cef426
cvc#64
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Tech237
Moderator
Username: Tech237
Post Number: 770
Registered: 4-2004
| | Posted on Monday, May 07, 2007 - 10:54 am: |
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Personally _ I would not trust it as a feed line. That is the sort of cable I throw in my junk box and use to make ground straps and MAYBE short jumpers out of.
Simon
Tech237
KD7IEB
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Dale
Advanced Member
Username: Dale
Post Number: 847
Registered: 12-2002
| | Posted on Monday, May 07, 2007 - 8:58 pm: |
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ok thanks tech237 what ya think happened to it?
dale/a.k.a.hotrod
cef426
cvc#64
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Tech833
Intermediate Member
Username: Tech833
Post Number: 129
Registered: 12-2001
| | Posted on Monday, May 07, 2007 - 9:06 pm: |
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I have cable that is 50 years old working just like new. Keep it sealed and you should never have to change it. |
Bruce
Senior Member
Username: Bruce
Post Number: 4438
Registered: 9-2003
| | Posted on Monday, May 07, 2007 - 8:39 pm: |
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dale
Put a connector on each end and measure the loss.
You can do this with a watt meter placed at each end ( one end at a time ) and the cable into a dummy load.
STILL even if it looks good it would be my 2nd choice .... old cable is a cr**-shoot.
On 6 since 66
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Romstar
Intermediate Member
Username: Romstar
Post Number: 103
Registered: 3-2007
| | Posted on Wednesday, May 09, 2007 - 1:16 am: |
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30 years, same coax. 70+ feet of RG-58/U.
1.1:1 SWR on almost every CB that gets connected.
Just like Timex, it takes a licking, and keeps on ticking.
I'm with 833 on this one. Check it from time to time, and don't mess with it unless you have to.
Romstar |
Tech237
Moderator
Username: Tech237
Post Number: 773
Registered: 4-2004
| | Posted on Wednesday, May 09, 2007 - 1:16 pm: |
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Romstar, if you look back at my original reply to this that is basically what I stated - if it appears damaged or a check shows loss, raised SWR etc than all is fine. If you see anything out of the norm than repair or replace.
Simon
Tech237
KD7IEB
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Romstar
Intermediate Member
Username: Romstar
Post Number: 105
Registered: 3-2007
| | Posted on Thursday, May 10, 2007 - 4:50 pm: |
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There are a lot of people who seem to replace coax on a fairly regular basis. This can be for a variety of reasons, but I think in many cases the coax is either not proplerly installed, subject to severe beating, or over loaded.
In most cases, good coax lasts. Too many people get into this routine of spending hundreds of dollars or more every few years replacing perfectly good coax because they either did something wrong, or becuase they didn't check the other components of their system.
It really bothers me when "mythology" costs good people money.
Romstar |
Tech237
Moderator
Username: Tech237
Post Number: 776
Registered: 4-2004
| | Posted on Friday, May 11, 2007 - 8:36 am: |
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Guess I better add another section to my Coax - Myths and facts article at some stage..
Simon
Tech237
KD7IEB
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Kirk
Intermediate Member
Username: Kirk
Post Number: 337
Registered: 6-2002
| | Posted on Thursday, May 24, 2007 - 10:51 pm: |
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I would add...inspect the jacket good! I had a similar question and in cable research online, 20 years seemed to be the 'norm', but...use your own judgement. I replaced a 50 ft. run of coax for a friend last year. It looked ok (from 5' away) but a close inspection revealed several cuts in the jacket, almost utility knife accurate. It was about 15 years old. When I picked it up, several sections cracked like January ice while other places were still flexable. The spots that cracked immediately split the jacket and you could see some corrosion. -- |
Dale
Advanced Member
Username: Dale
Post Number: 894
Registered: 12-2002
| | Posted on Friday, May 25, 2007 - 5:32 am: |
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thank-you guys.bruce im not clearly sure i understand how ya meaning to check it with a
wattmeter on one end and a dummyload at other end.but might give it a try cause i have both
dale/a.k.a.hotrod
cef426
cvc#64
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Bruce
Senior Member
Username: Bruce
Post Number: 4454
Registered: 9-2003
| | Posted on Friday, May 25, 2007 - 6:01 am: |
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feed 10 watts into a cable. MEASURE it at the input with a watt meter and use a dummy load to terminate the cable at the other end. MOVE the watt meter to the load end and remeasure the power .... if its 5 watts you lost 3DB .......
Unless you have some realy good generators and can read down below 1 db this is the best way to check a cable.
On 6 since 66
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Applejack
Intermediate Member
Username: Applejack
Post Number: 293
Registered: 8-2003
| | Posted on Monday, December 24, 2007 - 10:00 pm: |
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i changed my 12 year old rg8 in november because it runs up thru the chimney flue, i had new coax, i had time, and being over a half century old with arthritis in my knee, i wanted to do it while i could still climb. plus i used it as an excuse (reason) to put up a new Maco V5/8. aj |
