Joerg, is it the Fairchild logo?
John
Hi.
I also thought so at first glance, but it is not quite the same. Check this logo (too big of an image to add).
I have already seen this before...
Could be Ferranti... see http://en.wikipedia.org/wiki/File:Ferranti_logo.svg
Nope, not the famous Flying F logo of Fairchild, which was a slanted capital F. Here's the best compendium of semiconductor logos I've seen and this logo isn't among those listed:
http://www.classiccmp.org/rtellason/logos/semiconductorlogos.html
It looks like an "F" and a "T" to me. Can't think of a 1973 semiconductor company with those initials.
They used a simple "F" before and after 1973.
It seems only Unitrex/Eiko used this type of chip, I have a 1013, 1105, 1106 and #019 listed.
I found this as well: http://calculatorlaboratory.blog119.fc2.com/category4-4.html
Judging by the different housing, these might have been custom made for Eiko.
According to the following article, Caltex made calculator chips for Eiko in this time period:
I've never heard of Caltex, but that period saw a lot of semiconductor vendors come and go.
Joerg:
What type of chip is it?
Although they were best known for core memory (and the Bi-Tran Six educational computer), I think that Fabri-Tek made solid state memory chips.
For reference, here is a picture with a logo:
http://archive.computerhistory.org/resources/physical-object/fabritek/102643016.lg.jpg
-- Richard
It's a single-chip calculator circuit, we found out that it is the buggiest and weirdest chip ever. Found in the German Privileg 800 and the Unitrex 800k, both manufactured by Eiko in 1973.
Joerg
Would make sense - who knows their logo from the Seveties?
Thanks and Regards, Joerg
Fascinating and very in-depth article. Thanks. Took a little skim but, later I'll give it a good read.
Thanks Steve
Caltex uses a "CT" logo, the CPUs are named "CTxxxx". However this might be an OEM version done for Eiko, as the "golden legs" are commonly found on Caltex CPUs.
Judging by the article, as it states "Caltex manufactures a chip for Eiko", I'd say we can now be sure that these chips have been made by Caltex for Eiko - none of my Eiko calculators features a Caltex-branded CPU.
(Btw. it's true - the Caltex CPUs are a wicked piece of ****, no wonder, they disappeared from the market so soon...)
Edited: 3 May 2012, 3:13 p.m.
A 1974 chip with the Caltex logo can be seen here.
The style of package doesn't mean much. Lots of semiconductor makers bought packages from the same suppliers.
Edited: 3 May 2012, 4:23 p.m.