Hello Paul!
In a message to Wayne Sarosi  Paul Williams wrote:
PW> ........ (and
PW> this one beats all) a power supply from a rather large pbx.  The 12V
PW> supply I can use, but I have no idea what to use the 90VAC @ 20Hz for.
What the PBX system used it for... was to Ring the phones!  20 Hz@90VAC is
what rings the telephone.
Just my $0.02 worth.
Sid Ashen-Brenner N0OBM   Salina Packet Systems BBS
... The warranty: Bold print giveth & fine print taketh away.
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