smaller HP 82166A with 32-pin connector

[Klaus Overhage]

Hello Kim,
according to the data sheet, the HC version differs from the HCT-version only in terms of the input-voltages. The outputs are the same as voltages and currents.

I cannot find a data sheet for a 74HC473 on the internet. Is this a very old IC that was replaced by the 74HC573 some time ago? I think you better switch to a 74HCT573 with a 4069 or maybe 74HCT574.

I use a separate power supply for the LEDs and they are connected to the output of two 74LS00 against 5V via 330 ohms. A 7404 can do the same job.

I have build a cable from the HP 82165A to a Parallel Printer as described in the manual. And I have tried to read from and write to an old 8K SRAM with the help off some TTL-ICs that count the adress up. This SRAM circuit belongs to an old interface system for the Commodore 64, for which I have some plug-in cards and for example can write the results of an A/D converter into the 8k RAM.