[cctalk] Re: RS232 Spec

On 4/20/25 09:18, Martin Bishop via cctalk wrote: If one asks "why current loop?", the answer is obvious. Superb induced noise immunity I think, is the big one. If you're a musician on stage with a bunch of coupled electronic gear, bear in mind that EMI due to the lighting currents themselves is an issue. It's the reason that stage mics use a shielded pair. It's also why CL is used in industrial settings. From a pre-war 19th and 20th century setting, the reason is that not only does one gain noise immunity over long (miles long) runs, but that the required current for activation can simply be adjusted at one end by varying the voltage. --Chuck