NEC PowerMate power connector ?

[Dix]

I have to rerpair an old NEC PowerMate 286 wih broken power supply.
The ps is a TDK PU607.
I learned that there are 2 type of connectors on the market, an ATX 20
pin and an AT 6+6 pins.
Bur the NEC has a 9-pin and a 3- pin connector. No chance to get the
info from TDK nor NEC.

Colors from front to back:
br, br, bk then bk, bk, or, or, bk, bk, red, red,red (or=orange,
bk=black, br=brown)

All reds and all sw are connected in the supply (< 0.3 Ohms), while
browns are not connected.
Reds are probably +5V and orange are + 12 because the are connected to
the 4 pin hard disk power connector.

Any hints where -5 and -12V is ?

Thanks, Dieter

 

[John McGaw]

I have to rerpair an old NEC PowerMate 286 wih broken power supply.
The ps is a TDK PU607.
I learned that there are 2 type of connectors on the market, an ATX 20
pin and an AT 6+6 pins.
Bur the NEC has a 9-pin and a 3- pin connector. No chance to get the
info from TDK nor NEC.

Colors from front to back:
br, br, bk then bk, bk, or, or, bk, bk, red, red,red (or=orange,
bk=black, br=brown)

All reds and all sw are connected in the supply (< 0.3 Ohms), while
browns are not connected.
Reds are probably +5V and orange are + 12 because the are connected to
the 4 pin hard disk power connector.

Any hints where -5 and -12V is ?

Thanks, Dieter

It could be that the -5 and -12 are not connected. If they are then the
place they would logically be used is in the RS-232 port circuitry and
it should be possible to trace that out fairly easily. My understanding
is that some designers generate the negative voltage on-board rather
than taking it from the PS since the current drain is so small.

BTW, Have you looked online for a replacement supply? I entered TDK
PU607 into Google and got some hits but I didn't follow up on them.

 

[Dix]

Hi John

Thanks for the hint.
This PC contained old chips not the new Maxim type ones generating
their own RS232 voltaged.
I decided to port hard- and software to a newer PC and after many
trail and errors succeded.
You have an interesting web site.

Dieter