thad@cup.portal.com (Thad P Floryan) (03/20/89)
Re: Wolf Paul's questions (my answers posted since they seem to be of general
interest) ...
Q: "1. Does a 3b1 PS fit into a 7300?"
A: It should. Both supplies have the same mounting hole arrangement and appear
to be the same height, so vertical clearance should be OK for either a 7300
or 3B1 case.
Q: "2. Are there 220VAC or 240VAC versions of these power supplies available
(I just bought a 7300 and it looks like I will be moving to Europe
at year's end.)"
A: The AT&T UNIX PC REFERENCE MANUAL (the book with all the schematics) has an
appendix "International Version" in which is stated: "The electrical
specification for this equipment is 220-240 volts."
In general, many switching power supplies have a single jumper that permits
primary operation on either 120VAC or 240VAC. Having just returned from the
West Coast Computer Faire in which I was demo'ing the UNIXPC for the past 3
days in the AT&T Computer Users' Group booth, I'm pooped and unable to open
one of the machines right now to see if there IS a jumper on the UNIXPC's
power supply.
HOWEVER, rest assured that you can operate your UNIXPC in Europe using a
step-down transformer (external device), and my original doubts concerning
problems with a line frequency of 50 Hz have been cast aside due to the
successful operation of a 3B1 by Jim Sanchez of SYTEK in Brussels since
January 1988; his system has been (and still is!) operating 24 hours/day.
If you'd like Jim's email (uucp) address (via SYTEK in Mountain View, CA),
let me know; Jim enjoys correspondence and can tell you the mfr and model
of the stepdown transformer he's using.
Q: "3. Do you have an address where one can order one of these babies?"
A: Although I'm not certain this is the same subcontractor who mfd'd the
UNIXPC's power supplies, I have found this entry in one of my various
buyer's guides:
Power Systems, Inc.
12 Tobey Road
Bloomfield, CT 06002
ph: 203/243-0357
TWX: 710/425-8778
In case news has "expired" at your site, repeating the original info:
The 3B1 power supply is mfd by Power Systems, Inc. and is their model PS 1610-1
(Convergent part number D-65-00056-1, Rev. B). Its specs:
90-130 VAC, 245 Watts, 58-63 Hz
+5 VDC at 20 Amps
+12 VDC at 5 Amps
-12 VDC at 300 mA
The 7300 power supply is also mfd by Power Systems, Inc and is model PS 1569
(Convergent part number D-65-00042-00, Rev. E). Its specs:
90-130 VAC, 58-63 Hz
+5 VDC at 20 Amps
+12 VDC at 3.5 Amps
-12 VDC at 100 mA
Thad Floryan [ thad@cup.portal.com (OR) ..!sun!portal!cup.portal.com!thad ]