Btw, if you are looking for other relatively cheap early HP-IB peripherals, there are these:
Early HP-IB peripherals ======================= HP 59000 Series HP-IB Accessory Modules https://www.prc68.com/I/HP59000.shtml When HP first came out with HP-IB they also offered a line of HP-IB "Glue" accessory modules to help in constructing automated test systems. All these instruments predated IEEE-488.1 and do not have any of the IEEE-488.2 capability. That's to say they all use the "R2D2" type of commands. The example code is typically based on something like a 9825 calculator. Most have their covers held on with Pozi Drive 2 screws. eg HP Catatalogs 1978 pg 26, 1989 pg 562 HP 59301A ASCII to Parallel Converter HP 59303A Digital-Analog-Converter HP 59304A Numeric Display HP 59306A HP-IB Relay Actuator HP 59307A Dual VHF Switch HP 59308A Timing Generator HP 59309A HP-IB Digital Clock HP 59313A 4 Chan A/D Converter HP 59401A Bus System Analyzer HP 59403A Common Carrier Interface HP 59500A Multiprogrammer HP-IB Interface HP 59501A Isolated DAC/Power Supply Programmer (Isolated DAC) cat 1979 pg 228 Prices vary; some can be very cheap. The 59309A HP-IB Digital Clock is rare and expensive, and manuals are even rarer.
