AMI 7849DC in PGA package with gold pins. That's the only chip
in white ceramic PGA package I know of, besides IBM
80386 processors (scroll down to see the picture). AMI also
made some very nice looking processors, for example AMI
Comment from CENTiNEX:
For the AMI PGA white chip, the part number is the second line
of text on the chip. The first line (7849DC) is the date of manufacturing.
I deducted that information from 6 of theses chips I have, they
are plugged on old boards. There boards have the manufacturing
date written on it, and this date is the same as the first two
number of the first text line on the chips. Theses are series
of chips, seems to work together 1845-xxxx, 2574-xxxx etc.
On these boards, there is even two funny
looking white ceramic, GREEN painted chips, along with some white
Beckman's made chips, and few white chips, wich seems to be some
kind of memory, unknown manufacturer (logo is a "S").
Seems that all of these chips were made
for this system, because the part number of the boards uses the
same style of numbering as the chips got. These boards came from,
as far as I know, an old computer, dated around 75-76. There are
a "CBT" logo (with a large and styled B) on all of them,
and this logo is reported on what seems to be an ROM (white and
johnorun: The "B" logo he
(CENTiNEX) refers to is for BURROUGHS, which was a mainframe
computer maker, in NJ I believe. I have about 20 boards from a
Burroughs, all from 1975-77, and their hand-made tin circuitry is
pretty enough to hang in a museum! I have 6 of these white/gold
ceramic AMI chips on one board and 3 on another. I also received
this same chip from Windmiller marked with the Burroughs logo, not AMI!
I would guess the white chips with the "S" are Signetics? I have S
chips on several of my boards also, plus Mostek, Intel and even an
AMD Gold top ceramic.
Beckman 899-1-R1K chip in CerDIP package. Black printing on white
ceramic make chip look stylish.
Comment from Peter Glaskowsky:
The "Beckman 899-1-R1K chip in CerDIP package" ... is
a resistor network. I don't know the 899-1 prefix, but the R1K
suffix means a 1K-ohm resistance. Inside this package, there are
either seven independent resistors running from one side of the
package to the other, or 12-13 resistors each going from a common
pin to a different pin. Usually you can see the outline of the
resistors through the surface of the package, sometimes with the
aid of a strong light. Technicians usually use the visual-inspection
method to figure out what kind of resistor network is in the package,
rather than looking up the part number. :-)
Unknown chip in flatpack package soldered on a board.
Comment from Brad Thompson: The chip
... is quite likely a Sylvania SUHL ("Sylvania Universal
High-level Logic") IC, an early TTL family. The PC-board
frame allowed easy breadboarding and handling for test purposes.
As a co-op work student in the early 1960s, I actually constructed
a breadboard with a few of these ICs!