Expert: Marc Ebelini - 8/5/2009

Question
How does this radio connect to a single ended audio panel? Can the LO signals be strapped to ground? In the spirit of noise isolation, do I carry a ground from the audio panel to the LO output? If the KX outputs are truly differential then I would think this would offer some protection from ground loop induced noise.

Too bad, the KX-155/KMA-24 world ain't as clean as I thought it would be :)

Thanks!

Answer
With rare exceptions all electrical items should share a common ground. The ground is the reference point so using different reference points will cause a problem. Because it is simple enough to do, tieing things together to a ground should not be hard to do. Because the engine block is the ground reference because there is were the additional current supply comes from this is your common point. Sometimes ground wires that run any distance should be flat or ribbon type because this wire can become an antenna for strong RF or noise energy. Noise problems are commonly caused by poor grounding however I would also isolate your power source (Alternator or generator)to determine if it is adding to your problem. Never place audio signals to ground. They should always be terminated by the source impedance. If you need to ground it as you put it. Never short or open a speaker wire. Terminate it with a resistor of a value equal to it's impedance. Same goes for the phone output. This protects the source should you have it at full volume.
Why would the company provide something that is not needed if the equipment is stalled properly and or there is no defective power source or other poorly operating source. Once traced an noise problem that drove me crazy to an improperly repaired antenna cable. Never try to get the tail to wag the dog.