I can't find my scanned copy of the HP 1000 power supply manual which
has the details, but think the specified resistor plug value is
something 820, not 1K. In practice that difference might not matter.
On the 21MX "B" type power supplies the Battery Chager Board
(5061-1348) plugs into an empty slot on the power supply motherboard,
but the Battery Backup Board (5061-1349) replaces the Jumper Board
(5061-1351). I don't have a Jumper Board to look at and I can't find
the right manual with the schematic of the Jumper Board but I'm pretty
sure it has some components on it and the power supply would not
operate if neither it nor the Batter Backup Board were installed.
On Sat, 25 Dec 2004 19:28:24 -0600, Jay West <jwest(a)classiccmp.org> wrote:
On the HP power supply and cheater plug...
I'm fairly certain, although not positive, that you can "fix" this
A) Get a battery cheater plug. Of course that's the obvious answer. I think
it's a 1K resistor across pins 3 & 6. But...
B) I THINK that you can cleanly and effectively remove the battery backup
option from the HP power supply by opening the power supply and removing two
printed circuit cards. The power supply still works perfectly, just no
batter backup. I have never tried this, but I am quite sure that the battery
backup option could be added to a power supply which didn't include the
option. When you ordered this, you got two PCA's that went into the power
supply, plus the battery itself. So if you don't have the batter, and no
cheater plug, I think you could just remove the two PCA's and run fine.