What's this old cerdip chip?

[Grant]

Wondering what this 14 pin cerdip chip is, markings:

| 1 1124 1155B |
| 0 F 7331 <
| 4 |

The '104' text baseline is rotated to left, and pin 1 indent to the right.

Picture at http://grrr.id.au/image/cerdip-whatsit.jpg

Turned up in some junk parts a friend gave me.

Cheers,
Grant.

 

[Lostgallifreyan]

Grant <omg@grrr.id.au> wrote in
news:tnn4a6pflmp3uo25sq9iinf7onnei7etkt@4ax.com:

Wondering what this 14 pin cerdip chip is, markings:

| 1 1124 1155B |
| 0 F 7331
| 4 |

The '104' text baseline is rotated to left, and pin 1 indent to the right.

Picture at http://grrr.id.au/image/cerdip-whatsit.jpg

Turned up in some junk parts a friend gave me.

Cheers,
Grant.

Military markings? They use ceramic IC,s and might not want people to know
what's in them.

Another thought: precursor to 74 logic series? I have no clue if there was
ever a 73 series, btu if so you might have one there.

 

[Franc Zabkar]

On Wed, 29 Sep 2010 07:39:20 +1000, Grant <omg@grrr.id.au> put finger
to keyboard and composed:

Wondering what this 14 pin cerdip chip is, markings:

| 1 1124 1155B |
| 0 F 7331
| 4 |

The '104' text baseline is rotated to left, and pin 1 indent to the right.

Picture at http://grrr.id.au/image/cerdip-whatsit.jpg

Could the "7331" be a week 31, 1973 date code?

F = Fairchild ?

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.

 

[Tilmann Reh]

Lostgallifreyan schrieb:

Wondering what this 14 pin cerdip chip is, markings:

| 1 1124 1155B |
| 0 F 7331
| 4 |

Military markings? They use ceramic IC,s and might not want people to know
what's in them.

Another thought: precursor to 74 logic series? I have no clue if there was
ever a 73 series, btu if so you might have one there.

I'd rather think 7331 is the date code, and the type information is in
the first line - maybe some custom code, and/or military.

The "F" could be an indicator for Fairchild as manufacturer.

Tilmann

 

[Lostgallifreyan]

Tilmann Reh <usenet2007nospam@autometer.de> wrote in
news:i7unuv$1vv$1@news.eternal-september.org:

I'd rather think 7331 is the date code, and the type information is in
the first line - maybe some custom code, and/or military.

31st week of 1973? If so that could fit, it looks old enough.

The "F" could be an indicator for Fairchild as manufacturer.

I wondered that too, but I don't know if firms were as logo-happy then as
now. They got very flamboyant so we can't confuse them with anything else,
but in those days I have no idea what they did. I think Fairchild are one of
the oldest though, so I agree it might mean them.

 

[Tilmann Reh]

Lostgallifreyan schrieb:

I'd rather think 7331 is the date code, and the type information is in
the first line - maybe some custom code, and/or military.

31st week of 1973? If so that could fit, it looks old enough.

At least it appears possible.

The "F" could be an indicator for Fairchild as manufacturer.

I wondered that too, but I don't know if firms were as logo-happy then as
now. They got very flamboyant so we can't confuse them with anything else,
but in those days I have no idea what they did. I think Fairchild are one of
the oldest though, so I agree it might mean them.

In those early years, Fairchild often printed just that single letter
"F" on their ICs.

Tilmann

 

[Grant]

On Wed, 29 Sep 2010 08:56:36 +0200, Tilmann Reh <usenet2007nospam@autometer.de> wrote:

Lostgallifreyan schrieb:

Wondering what this 14 pin cerdip chip is, markings:

| 1 1124 1155B |
| 0 F 7331
| 4 |

Military markings? They use ceramic IC,s and might not want people to know
what's in them.

Another thought: precursor to 74 logic series? I have no clue if there was
ever a 73 series, btu if so you might have one there.

I'd rather think 7331 is the date code, and the type information is in
the first line - maybe some custom code, and/or military.

Or telecomms? I think the 7331 is data code, going be the age of the plastic
tape around the IC carrier, a piece just long enough for one chip, perhaps
carried as a spare?

The "F" could be an indicator for Fairchild as manufacturer.

Be my guess too. I have no idea what the chip is though.

Grant.

 

[Cydrome Leader]

Franc Zabkar <fzabkar@iinternode.on.net> wrote:

On Wed, 29 Sep 2010 07:39:20 +1000, Grant <omg@grrr.id.au> put finger
to keyboard and composed:

Wondering what this 14 pin cerdip chip is, markings:

| 1 1124 1155B |
| 0 F 7331
| 4 |

The '104' text baseline is rotated to left, and pin 1 indent to the right.

Picture at http://grrr.id.au/image/cerdip-whatsit.jpg

Could the "7331" be a week 31, 1973 date code?

F = Fairchild ?

- Franc Zabkar

I don't know for sure, and looked at the photo first and my best guess was
Fairchild and made in 1973 as well. The rest of the numbers don't mean
much- could be house markings or something like a 12 gate IC that was
discontinued in 1974.

 

[John Robertson]

Grant wrote:

Wondering what this 14 pin cerdip chip is, markings:

| 1 1124 1155B |
| 0 F 7331
| 4 |

The '104' text baseline is rotated to left, and pin 1 indent to the right.

Picture at http://grrr.id.au/image/cerdip-whatsit.jpg

Turned up in some junk parts a friend gave me.

Cheers,
Grant.

If you have a Xeltek Eprom burner you can use it to identify many TTL
and CMOS parts - I think a few other burners may have this function as well.

Or it may be a PROM

John :-#)#

--
(Please post followups or tech inquiries to the newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

 

[Michael Black]

On Mon, 4 Oct 2010, John Robertson wrote:

Grant wrote:
Wondering what this 14 pin cerdip chip is, markings:

| 1 1124 1155B |
| 0 F 7331
| 4 |

The '104' text baseline is rotated to left, and pin 1 indent to the right.

Picture at http://grrr.id.au/image/cerdip-whatsit.jpg

Turned up in some junk parts a friend gave me.

Cheers,
Grant.

If you have a Xeltek Eprom burner you can use it to identify many TTL and
CMOS parts - I think a few other burners may have this function as well.

Or it may be a PROM

The thing is, circa 1973 (and that seems like a good guess, that the

"7331" is the date code), ceramic packages were fairly common. It was
kind of on a cusp, ICs were seeing a lot of use but nothing like what came
later. A lot was still in ceramic, there wasn't yet enough demand to make
it in a cheaper package. Remember, this was the time of 265bytes in a RAM
IC, and only one-bit wide, or more likely long shift-registers for memory.
I'm sure that RAM I bought at PolyPaks about 1973, not having more than
256bits, was a ceramic package.

The 7400 series was usually plastic, but ceramic was not uncommon at that
point (though, I'm not sure if just happened to come in ceramic, or if it
was rejects from the tighter-spec'd 5400 series).

The point is that at that time, having a ceramic package might not be much
use in defining the IC, other than it isn't likely to be a
consumer-oriented IC.

Michael

 

[Grant]

On Wed, 6 Oct 2010 13:18:52 -0400, Michael Black <et472@ncf.ca> wrote:

On Mon, 4 Oct 2010, John Robertson wrote:

Grant wrote:
Wondering what this 14 pin cerdip chip is, markings:

| 1 1124 1155B |
| 0 F 7331
| 4 |

The '104' text baseline is rotated to left, and pin 1 indent to the right.

Picture at http://grrr.id.au/image/cerdip-whatsit.jpg

Turned up in some junk parts a friend gave me.

Cheers,
Grant.

If you have a Xeltek Eprom burner you can use it to identify many TTL and
CMOS parts - I think a few other burners may have this function as well.

Or it may be a PROM

The thing is, circa 1973 (and that seems like a good guess, that the
"7331" is the date code), ceramic packages were fairly common. It was
kind of on a cusp, ICs were seeing a lot of use but nothing like what came
later. A lot was still in ceramic, there wasn't yet enough demand to make
it in a cheaper package. Remember, this was the time of 265bytes in a RAM
IC, and only one-bit wide, or more likely long shift-registers for memory.
I'm sure that RAM I bought at PolyPaks about 1973, not having more than
256bits, was a ceramic package.

The 7400 series was usually plastic, but ceramic was not uncommon at that
point (though, I'm not sure if just happened to come in ceramic, or if it
was rejects from the tighter-spec'd 5400 series).

The point is that at that time, having a ceramic package might not be much
use in defining the IC, other than it isn't likely to be a
consumer-oriented IC.

May have been a house part for telecomms industry, as that's the area my
friend worked in for a long time. I started working in electronics mid 70s
and mostly opamp ICs where what I saw until late '70s.

Glad I'm not the only one wondering what the thing is.

Grant.