72VDC power?

From: Joe R. <rigdonj_at_cfl.rr.com>
Date: Tue Mar 16 10:26:35 2004

At 11:57 PM 3/15/04 -0800, you wrote:
>On Tue, 16 Mar 2004, Joe R. wrote:
>
>> I picked up a couple of rack mount computers last week. Most of them were
>> made by Harris and Texas Micro and are MOL standard passive backplace type
>> stuff. However one of them was made by Kontron and it has a very strange
>> power connector. It's a black cylinder about 1 1/4" in diameter and about 1
>> 1/2" long that sticks out of the chassis. The back half of the cylinder is
>> threaded so it appears that the mating connector screws onto it. The front
>> portion of the cylinder is divided lenghtwise into five segments. Four of
>> the sements have holes in them with a male connector pin resessed into the
>> holes. I opened the chassis and found that it was marked as being built to
>> operate off of 72 VDC power and that all four connecotr pins are wired tot
>> he PSU. Is anyone familar with the type of connector or why or where they
>> use 72 VDC power? The computer doesn't look like anything exceptional. It
>
>It probably ran off of batteries, possibly in a telco environment, where
>that supply was readily available.

   Sorry but the telcos all use 48VDC AFIK. I used to install CO equipment
and that's what was used in every office that I saw. They may use 72VDC or
other voltages overseas, I don't know, but AFIK all the offices in the US
are 48VDC. I wondered if this might actually run off of 48VDC but that's
about a 33% difference so it would be questionable in my mind. One of the
things holding me back from testing it is the lack of a suitable high
currect power supply. I have access to plenty of high current 48VDC
supplies (telco surplus) but high current supplies over 48V aren't that
common.



>
>> has a 10 MHz 286 CPU and uses a 9" CRT in it for the monitor. The only
>> thing of real interest in it was a GPIB card. This one was made by INES
>> (IIRC) in Germany. I've never heard of this brand before. The chassis does
>> have one odd feature. The motherboard sits crossways in it and there are
>> cables that plug into the back panel connectors of the various cards
>> (they're now on the RH side of the computer since the MB is sideways) and
>> run around to the back of the computer and connect to connectors there.
>
>Is there any shielding? I have an tempest-shielded IBM PC that's kinda
>like this except the cards are in the standard orientation. Anyway, what
>you describe reminds me of that system.

    You might be right about tempest shielding. This is a VERY solidly
built unit with plenty of metal covers and such. I didn't notice any RFI
gaskets but they might not be needed. The back panel with the IO connectors
is a solid metal plate with no joints to act as slot antennas.

     Joe
Received on Tue Mar 16 2004 - 10:26:35 GMT