HP-65 and HP-67 card reader how to test the amplifier ?

[albertofenini]

Hello everyone,

I have three card readers, all from HP-67 units that apparently don't works

All the CPU boards units when coupled with a working card reader can read and write
which in way proves that the 1820-1751 and the ACT chips work as they should.

All of the card readers have the plug-in connectors rather than the soldered cables,
and I'm thinking of removing these connectors and solder the head and motor cables
to provide a better and more reliable connection

However, prior to do so I was wondering if there is any technique that can help me in
check that the 1826-0322 sense amplifier (BTW all of three have this version) works

Thanks for help and take care

card readers pictures here : HP-65 Card readers