22 Nov
1997
22 Nov
'97
1:26 p.m.
On Sun, 23 Nov 1997, Tony Duell wrote:
Eh??? What beep?? AFAIK no BA11 had a beeper fitted as
standard.
Pretty.
Firstly, BA11 covers a heck of a lot of PDP11 mounting boxes, from the
tiny BA11-V (4 dual-height Q-bus slots in a case the size of a TU58 tape
drive) up to at least a BA11-F (21" high rackmount thing with over 30
slots, and a separate H742 PSU). What mounting box are you working with?
BA11-K.
Secondly, some switch-mode PSUs will make audible
noises if they're
overloaded (shorted), or if they're unhappy for some other reason -
basically the trasformer/inductor core vibrates at the switching
frequnecy, and this may fall into the audible range. A few also do this
if the load is too light - so if you run them with no load they may well
do this. That sounds like what's happening here.
That's it. I can ignore that?