TO: ALL WOOD COUNTY ARES MEMBERS (OFFICIAL)
ALL ARES AND NON-ARES AMATEURS ANYWHERE (INFORMATION)
FROM: KEN HARRIS WA8LLM ARRL DISTRICT 3
EMERGENCY COORDINATOR WOOD COUNTY EMERGENCY COMMUNICATIONS INC.
WOOD COUNTY ARES BULLETIN NR 20.16 DATE: April 19, 2020
SUBJECT: GROUNDING YOUR EQUIPMENT
As radio operators we sometimes tend to forget a very important operation, grounding. Stray Radio Frequencies (RF) are all around us. These frequencies need to be suppressed before they enter the receiver from some way other than the antenna input.
RF signals that enter a receiver from other than the antenna can be in the form of Static, Secondary Emission, or AC Induction. Static can be lightening, or motor ignition noise. Secondary Emissions are signals that are generated from the results of superhetrodyne mixing in other receivers. AC Induction comes from receivers being placed too close to strong magnetic fields being produced by power transformers or motors.
When signals enter receivers from other than the antenna input, they can cause some of the automatic circuitry in the receiver to overload, causing the receiver to be less sensitive to the wanted signals. To prevent these unwanted signals from entering a receiver, the receiver should be grounded, allowing unwanted signals to be shorted to ground. Heavy wire or cable should be used for grounding.
Another reason for grounding is lightening protection. Grounding receivers, transmitters, and transceivers helps to allow a direct or indirect lightening strike pass safely to ground without running wild in the radio shack.
Ken Harris WA8LLM
Wood County WV
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