5 Feb
2012
5 Feb
'12
12:04 a.m.
On 04/02/2012 20:17, Tony Duell wrote:
Absolutely. A colleague once told me about equipment he worked on in
telephone exchanges. He wondered what the -43V supply was for, until he
realised it was the power rail for the TTL. The -48V was the "ground"
for it.
--
Pete Peter Turnbull
Network Manager
University of York
The board itself is supplied with -5 and -15 volts, so nothing on the
board is TTL.
Egh> You ave a 5V supply between ground (+ve) and the -5V rail (-ve).
That could bn sued to run TTL.
I've not seen the board but I don;t think I can say from what you've told
us that there can't be any TTL on the board.