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Arizona Repeater Association, Inc
P. O. Box 35758, Phoenix, Arizona 85069-5758

W7ARA

Arizona Repeater Association, Inc

Dealing with Interference

Types of Interference

The person who causes malicious interference might do it for one of
these reasons:

When malicious interference occurs, the main desire should be to eliminate the interference. Finding the person and talking to, or reprimanding him may not be the best way to solve it. He may continue, trying not to get caught the next time. The best way to remove the interference is to discourage the person doing it, so that he does not have the desire to continue. Many times he does it to get attention. If he is ignored, he may go elsewhere to play or quit altogether.

Guidelines for handling a jammer on the air:

1) DO NOT ACKNOWLEDGE INTERFERENCE OR THE INTERFERER.
Do not talk to him or about him. If he is unlicensed, talking to him is against the law. If possible continue your QSO as if the interference didn't exist. If that is not possible, move to another freq or tell the other person you've got things to do and will contact him/her later. Do NOT let the interferer know you have even noticed him. If his audience goes away, so will he.

REASON: Most "malicious" interference is done to get attention. When you acknowledge the interference, you have given him the attention he wants, which encourages him to continue. If he doesn't get noticed, he'll go somewhere else where he will get noticed.

 

2) WAS THERE A COUTRESY BEEP? Did you hear the repeater's courtesy beep after the interference? Did it sound normal, or was it from a link?

REASON: On many linked systems, the courtesy tone changes depending on where the transmission originated. On ARA systems, two beeps of the same tone indicate the transmission was from that repeater. If the tones are different (hi-lo, etc.) then it came from one of the link repeaters. Try and note this information for the interference report. If you don't hear a courtesy tone after the interference, it is probably originating on the output frequency. It could even be caused by intermod.

 

3) LISTEN ON THE INPUT FREQUENCY to see if you can hear the interference direct. Make note of your findings for the interference report.

REASON: This is one of the most important pieces of information to pass on to the interference committee. If the above methods fail to control the interference and we have to locate the interferer, we need to know where he can be heard on the input frequency. With hams in every part of the state, someone will be able to hear the interference directly. With that information, we can put mobile Doppler and Transmitter Fingerprinting in that area.

 

4) RECORD THE INTERFERENCE on tape if possible. Label the tape, then seal it in an envelope. Date and sign the envelope.

REASON: We need to have as many samples of the interference as possible to aid in locating and eliminating it. If action proceeds beyond the local level, we may need to demonstrate the chain of custody of the tape. That is where the sealed envelope comes in.

 

5) CONTACT THE INTERFERENCE COMMITTEE, immediately if possible. Then fill out and file an interference report, including your tape. If you are submitting a tape, it is better to hand carry both it and the interference report to an interference Committee person. That prevents breaking the chain of custody. The Interference Committee will replace any tapes submitted.

REASON: Very little can be done about interference that occurred yesterday. We need to get to work on the problem while it is happening. The follow up report goes into the database, and as they come in from different sources, they paint a picture of the problem. It is these reports that drive the Interference committee.

 

The following was found as one of the guidelines for the ZIA Connection.
It also represents ARA’s policy and that of most repeater systems:

If you hear a jammer, IGNORE HIM. Resist the temptation to 'set the jammer straight'. Simply don't acknowledge his presence. If the jammer has no audience, he will soon be gone.

Arizona Repeater Association - Local Interference Committee

Send interference reports to:

A.R.A. Interference Committee
Dennis Bietry - KE7EJF Chairman
Phone: (602) 274-3732

On-Line Interference Report or Email: interference@w7ara.net

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