MR CB IGNITION SPARK PLUG DISTRIBUTOR Radio Noise SUPPRESSOR Car Truck 2-Pack
NEW OLD STOCK IGNITION NOISE-RADIO INTERFERENCE SUPPRESSORS
FOR CARS, TRUCKS, MOTORCYCLES, EQUIPMENT.
Install one on each spark plug.
Mr CB Division/ JASCO Products Co, INC
# 7054
Spark plug interference is heard as a popping noise in the radio receiver which increases to a loud buzz as engine speed is increased. Use of a resistor-type spark plug is an effective way to suppress this kind of interference. The nearer the resistor to the spark gap, the more effective it is; the resistor tends to isolate the cable from the noise in the spark plug. The less noise in the cable, the less it radiates. Also, the high frequency part of the spark is "chopped off.
The automobile with an internal combustion engine generates a large amount of electromagnetic interference. The engine utilizes a high voltage ignition system to ignite the fuel. The ignition system produces short impulses that generate a broad spectrum of frequencies. Other sources of EMI located within vehicles include motors that are used for blowers, windshield wipers, buzzers used for ignition and seat belt warnings, and voltage regulators that utilize points that open and close frequently. All of these devices generate interference in a frequency spectrum from the kilohertz range up to the gigahertz range. The fact that vehicles generate EMI has been known since the advent of AM radio in the 1930's, when noise generated by the engine was readily detectable by the automobile radio.
This is for older vehicles and engines.
Newer models have built in units.