A/B schematic question

[rschultz]

Hi,

   See beavis schematic. Why does it short the side not in use to ground? If A is ON, B is shorted to ground, and vice versa. What if you didn't do this?

Thanks.
Ryan

[teemuk]

Cables with one end left "floating" without proper termination are like antennas anf can pick up interference and hum, which is then fed to A or B output, which ever is not use at the time. When you terminate the unused cable end by grounding it you effectively reduce the effect a lot and you won't have unwanted noises bleeding to the unused channel.

[EATyourGuitar]

the cable becomes an antenna. you dont want grounds connected to devices that aren't really doing anything anyway. by grounding the tip of B, you will never have a difference of voltage and thats almost as good as disconnecting both the ground and tip from B. its a metal box and you can never disconnect the grounds so grounding tips when not in use is the only way to keeps things off and quiet when not in use.

[rschultz]

Thanks for the responses, good to know.
Thanks.
Ryan