TO: ALL WEST VIRGINIA ARES MEMBERS (OFFICIAL)
ALL ARES AND NON-ARES AMATEURS ANYWHERE (INFORMATION)
FROM: KEN HARRIS WA8LLM WV SECTION EMERGENCY COORDINATOR
WOOD COUNTY EMERGENCY COMMUNICATIONS INCORPORATED
WV ARES BULLETIN NR 10.20 DATE: May 16, 2010
SUBJECT: DISABLE THAT SPEAKER
Are you the System Operator of a Remote, Hilltop, or Mountain Top Packet Radio System, or the Control Operator of a Voice Repeater? Are you sharing a transmitter building with other users? If the answer is yes, then you should disable the speakers of these systems.
If you've ever been at a transmitter site that does not have the speakers disabled on the other systems you'll know what I'm talking about. While you're working on your system it's easier to find your problem, if all other radios are quiet. But if there are other noises in the building, it makes finding your problem even harder.
It's not done intentionally to disable another user’s radio system, but it does happen. You, or another service technician, may turn the volume of another system down so as to hear the radio being worked on. You, or they, may forget to turn the volume back up when they leave, and sure enough you, or they, leave a trouble for someone else to fix.
Some radio systems use the volume control to adjust audio level going into a telephone line. Some Packet Stations use the volume control to adjust the audio level going to the TNC (Terminal Node Controller). If the volume on either of these systems gets turned down, the system is crippled, or disabled completely.
If your system uses the volume control to adjust the level, then it's best if you disable the speaker, and terminate the receiver audio, with a resistor. If the speaker output of a receiver is rated at 8 ohms, a 10 ohm resistor will do just fine. If the receiver or radio has an external speaker jack which cuts off the internal speaker, use a plug that has a 10 ohm resistor connected to it.
If you're unable to cut off the speaker audio by plugging into the external speaker jack, then you should connect a switch into the speaker circuit. Wire the circuit so the switch will terminate the receiver audio output when the speaker is turned off. Disabling the speaker may save you an unnecessary trip to the Hill or Mountain Top, and relieve you of the worries that your radio system may have been hit by lightening or been stolen.
(Reprint, with modifications of, District 3 ARES Bulletin NR 06.06)
Ken Harris WA8LLM
Wood County WV
WV ARES Section Emergency Coordinator
WV ARES District 3 Emergency Coordinator