On Tue, 4 Jan 2005 11:36:50 -0000, "Martin Underwood"
wrote:

"Martin Rich" wrote in message
.. .


Incidentally http://www.bt.com/archives/history/19241931.htm and
scroll down to 1925 reveals that the A/B button system was introduced
in 1935 and the very last ones in the UK weren't discontinued until
1992

Gosh, I hadn't realised that Button A/B phones lasted as long as 1992 in
some places - that's about the time that the post-payment "pips" phones were
starting to be replaced with modern pre-payment phones. Life goes
full-circle!


The pay-on-answer phones must have almost disappeared by 1992. BT's
archive web pages have the first 'blue payphone' (the first
modern-type prepayment phone) in 1979 and the 'blue payphone 2'
(presumably the production model used in large numbers) introduced in
1983. My memory, which could be inaccurate, is that for a couple of
years around 1983/4 the prepayment phones were common in busy places,
but pay-on-answer phones were the norm elsewhere. However, after that
the pay-on-answer phones were phased out rapidly.

In fact one possible explanation is that in 1992, modern prepayment
phones were finally being rolled out to remote areas, and this
included the few public phones that skipped the pay-on-answer phase
completely. According to the BT archives, the handful of A/B button
phones in Scotland survived because they used radio links which didn't
support the meter pulsing necessary for the pay-on-answer phones. So
it's possible - and I wonder if anybody reading this actually knows -
that the last A/B button boxes disappeared at around the same time as
the last pay-on-answer phones.

Martin