Hello Paul,


I think this item pre-dates a lot of this digital stuff; I doubt
there's a single eprom in it - and no custom chips, either!
It was built in about 1980 and doesn't go through any self-testing
routines. One has to carry out manual tests oneself. This wonderful
simplicity should hopefully enable me to keep it running indefinitely,
once I can get it fixed. Serviceability is one of my main criteria when
choosing an item of test equipment.


The HP4191A is from that era as well. However, it is one heck of a
complicated machine with a computer board as large as a family-size
pizza. Lots of PROMs and stuff :-(

Regards, Joerg

http://www.analogconsultants.com