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 too hot as summer. A lot of people are looking for outside projects after a long winter so spring is the best time for this important task.
Why should I rotate my coax? Well, for the same reasons you rotate your tires; even out the wear. On receiving antennas electrons flow in only one direction; from the antenna to the radio. Eventually that wears down the makeup of the copper in the center conductor of the coax. The breakdown at a molecular scale adversely affects the ability for the copper to conduct electrical impulses. Since RF signals on receive antennas are so miniscule to begin with, this can negatively impact the ability for the coax to pass weak signals.
Strong signals don't suffer as much of course, as they can overcome to broken down molecular structure of the copper as it ages. Weaker signals are attenuated at a higher level as they do not have the strength to push thru the degraded copper. This causes weaker signals to be even more weak or even not heard altogether.
Rotating the coax will allow the copper's molecular structure to wear at a more even pace. Since the effect is, of course, directional, those weaker signals are heard just fine again once you reverse the coax.
The biggest issue with rotating coax (and why so many people do not bother with it) is that it is a lot of work to take it down and put it back up again. Also there sometimes are issues with connectors. If you have a BNC on one end and a PL-259 on the other, you may have to use adapters or cut off the connectors and install new ones. It is for this reason that I always buy my coax a few feet longer than needed so that I can cut the ends and install new connectors each spring. Some of them have the same connectors at both ends so it isn't an issue. I could use adapters, but they cause other problems.
Now that the weather is warming up (and before it gets too hot here in the desert) I am going up in the attic and pulling all my coax to I can reverse them. I always label my coax with a red tape on one end and blue on the other, so in even years I have blue ends in the shack and red at the antennas. Odd years are, of course, reversed.
By properly rotating your antenna coax it will last much, much longer than without. I have some coax that is 40 years old and is still going strong, having been rotated almost every year since I bought it! You probably could get away with going 2 years between rotations but I wouldn't suggest going much longer than that as the molecular breakdown might get to the point where it is irreversible.
If you have made it this far then hopefully you have checked the date of this post.
Why should I rotate my coax? Well, for the same reasons you rotate your tires; even out the wear. On receiving antennas electrons flow in only one direction; from the antenna to the radio. Eventually that wears down the makeup of the copper in the center conductor of the coax. The breakdown at a molecular scale adversely affects the ability for the copper to conduct electrical impulses. Since RF signals on receive antennas are so miniscule to begin with, this can negatively impact the ability for the coax to pass weak signals.
Strong signals don't suffer as much of course, as they can overcome to broken down molecular structure of the copper as it ages. Weaker signals are attenuated at a higher level as they do not have the strength to push thru the degraded copper. This causes weaker signals to be even more weak or even not heard altogether.
Rotating the coax will allow the copper's molecular structure to wear at a more even pace. Since the effect is, of course, directional, those weaker signals are heard just fine again once you reverse the coax.
The biggest issue with rotating coax (and why so many people do not bother with it) is that it is a lot of work to take it down and put it back up again. Also there sometimes are issues with connectors. If you have a BNC on one end and a PL-259 on the other, you may have to use adapters or cut off the connectors and install new ones. It is for this reason that I always buy my coax a few feet longer than needed so that I can cut the ends and install new connectors each spring. Some of them have the same connectors at both ends so it isn't an issue. I could use adapters, but they cause other problems.
Now that the weather is warming up (and before it gets too hot here in the desert) I am going up in the attic and pulling all my coax to I can reverse them. I always label my coax with a red tape on one end and blue on the other, so in even years I have blue ends in the shack and red at the antennas. Odd years are, of course, reversed.
By properly rotating your antenna coax it will last much, much longer than without. I have some coax that is 40 years old and is still going strong, having been rotated almost every year since I bought it! You probably could get away with going 2 years between rotations but I wouldn't suggest going much longer than that as the molecular breakdown might get to the point where it is irreversible.
If you have made it this far then hopefully you have checked the date of this post.
