19 Feb
2012
19 Feb
'12
6:23 a.m.
On 02/18/2012 03:21 PM, Tony Duell wrote:
That makes sense; they're pretty simple. I'll yank it and check
those capacitors, that's what I was figuring it was anyway, but I
generally like to have schematics (if possible) before tearing into
something.
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
Hey, does
anyone have an electronic copy of the schematics for the
DEC 874-D power controller? I looked on bitsavers and didn't see
anything there, my paper originals are 1200 miles away, and I have an
874-D "buzzing" and dropping power periodically. Yuck!
My experience wih DEC power controllers (in general) is that thy;'re very
simple, and you can trace out the scheamtic of the control electronics in
half an hour maximum,. For the rest of it, it takes longer to draw the
components than to figure out what they do.
Much of the time a controlelr that buzzes/chatters has a dried-up
smoothing capacitr for the supply to the control electronics. I'd check
any sizeable electrolytics first.