June 9, 2011

Cables Do Deteriorate!

The cable guy learns! Recently my Astro(cable TV subscription) channels started to look like the picture above. It had a grainy, pixelated quality to it, and eventually the channels would drop out of service(meaning no picture, or sound). I called the service dept of Astro, which promptly sent a technician to my place to check out my complain.

The technician first suspected my set top decoder, which is more than 10 years old by the way, has developed a fault. He swapped in a new slim line, set top unit of the latest design, the fault persist. He proceeded to check the out door mounted satellite dish, no problems there. Then he said the mostly likely problem is the aged coaxial cable linking the receiver dish and the set top decoder. The use of a signal generator on one end and using the built in signal meter on the decoder unit proved that the cable was indeed impeding the signal transfer(a.k.a. signal loss). I remembered when I installed the Astro system in my home 8 years ago, the decoder signal meter showed 78% signal at the decoder. It showed 44% today.

Like fine wine, the coaxial cable has aged! Unfortunately, fine wine taste better when aged, where else aged cables just lose their transmission properties, slowly over time. A new cable was installed, I paid for the service, problem solved!

I used to advocate buying used high end audio cables for budget conscious audiophile, just as I've done so my self. With this episode, I've come to suspect that perhaps audiophile cables are just as prone to lose their signal transmission properties over time, without us even knowing it?

Granted, high end audio cables have better metallurgy, insulation material and termination quality compared to the industry standard coaxial cable used by our Astro installers. The question is, if the industry standard coaxial cable took 8 years to age to the point of non-function, how long would it take for a high end audio grade cable to lose it's transmission properties?

Would 10 years be a fair estimation? Are used high end audio cables still a good buy, especially those more than 5 years old? Only you, can answer that, unfortunately. So let buyer beware.


r.crawley said...

Dish cables are out in the sun and rain, my hifi cables are not! Rain can run down coax all the way into the box.

Ken said...

The worse that the hifi cables can have is oxidation of the banana plug which can be easily dealt with.

Capernaum Creative Solutions Inc. said...

Well made cables can last quite a while. 10, 20 years should not be a problem, IMHO. They are sealed well preventing oxidation. What you want to look out for is internal oxidation of the metal at molecular level. Purer metals will of course fare better in the long run. However, internal ocidation does stop and stabilize too if external atmosphere do not leak in.

High current handling cables have a higher failure rate than low current handling cables. I.e, speaker cables easier to deteriorate than I.C cables, etc.

Satelite dish cables aren't the highest quality and they are not very well sealed from atmospheric contaminants. Just look at the plug they use for termination. Mine failed less than a year. Then I swaped to a higher quality NOKIA issued RG6 variety and it has been more than 12 years now. I just had my Astro Beyond installed a month ago using the same 12 year old cable.

Signal quality 99%. Signal Strength 100%

I redo my dish/decoder termination once every 2 years. That's the starting point of cable failure.

Big E said...

Thanks for the assurances on hifi cables guys.

I appreciate your response.