why do telecommunication circuits use negative voltages?
for example the use of -48 or -24 volts in telephone exchanges and PABXs
Answer:
Using a negative voltage with respect to ground was to prevent corrosion that would occur if a positive voltage were used. That was the traditional way of measuring voltages
when AT&T originaly came out with telco services in the early part of the century.
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why do telecommunication circuits use negative vol..
for example the use of -48 or -24 volts in telephone exchanges and PABXsAnswer: Using a negative voltage with respect to..
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