Difference between HP41CV and CX halfnut?

[Ken S]

(11-12-2019 12:07 AM)hth Wrote:  

(11-10-2019 10:59 PM)Ken S Wrote:  On the halfnut HP41s, is the only difference between a CV and CX the second circuit board attached on the CX? In other words if I soldered the 2nd board from a CX onto a CV would the CV effectively be a CX with the time, extended functions and extended memory?

Thanks,

Ken

If that board is missing on the CV, I believe doing what you suggest will make it a CX minus the stickers. I wonder how they crippled the halfnut 41C model not to be a CV?

Thanks for that. I will give it a shot and see if it works and report back. I have a halfnut CV which after cleaning the battery terminals works fine and a CX which was damaged pretty badly by leaked batteries with some keys locked up from corrosion.

I think all the ram and rom are on one chip for the base 41 functions, I wonder if they just leave some connections on the chip un-soldered from the board? Be a lot cheaper than making a second chip just for the 41C