We have received some calculators: a couple of CV units and a CX unit - all of them half-nut.
What is a half-nut unit? The original HP41 calculators were build with two circuits: one for the keyboard and screen and another for the processor. All parts were soldered through holes, the "old way".
Around 1985-1986 HP had developed far better circuit-making, and they developed a single circuit, surface mounted with just one IC. This model (which was done as C, CV and CX too) was called "half-nut", and the previous model was the renamed "full-nut". Performance of both is identical, but half-nuts have several more "failure modes" than the full-nuts!
We test all units with the test pack of the HP41CV Service module.
It is an opportunity to get a dependable, tested and revised HP41CV or HP41CX with the full set of memory,
You can add some of our modules that you can find in the HP41C corner.