[GreenKeys] Another question for old Bell System guys

Larry Tighe larryradio at worldnet.att.net
Tue Dec 16 10:26:49 EST 2008


Jim,

Where did the 130 VDC come from?  I've only seen the huge 48 VDC battery 
banks and the 80-120 VAC 20 cycles for ringing.  I do remember 130 VDC for 
the coin collect/return relays in payfones...did it come from inverters???

lar 



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