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The HP41CL - our first conversion

Just received the hp41cl pack. I have several Calculator donors that will fit the bill.

The package presentation is excellent! I ordered the main board, the serial interface and the serial cable. All were independently packed, the main board in anti static  folder; and everything well protected in bubble wrap.

I plan to assemble it this afternoon. I palm to offer this as a service to our customers. It happens that I have some suitable calculators to modify, so I will offer them as pack too.


I have finally assembled it. It worked from the first time! I used a CV calculator that had good screen and keyboard but that had been severely damaged and repaired in the past. I figured that it would be better to test it with the worse calculator. Lets then try to upgrade one of my better ones.

Here are a couple of pictures.

A new calculator is born!


Fuller view of the birth of the HP41CL


The kit comes even with proper labeling that substitutes the original:


The speed is fantastic! I have put mine on Turbo50 (50 times faster than the original) and it really improves the speed.

I have included the serial interface. So far I have no need to include any more images (that’s what the serial interface is for). I have put the infrared printer module, and it worked the first time. I need to locate now a time module (does anyone have a spare one?), and I will leave the remaining slot for my HP-Il interface (in order to connect my HP-3468A multimeter). I guess that I will have then a quite complete device! (I am missing the timer functions that I have with my HP41cx - it really helps when you want to take multimeter measures at given times - it cannot be a match of a humble iPhone when it comes to convenience for anything else)

So far I have only included the Advantage module in slot 2. First I tried to do it in slot one but then I destroyed the additional memory management functions. I had to reinstall them again!

Please look at it running the TVM program of the Advantage pac:


And here, printing with the infrared module in slot 4:


I am offering it as a service (you supply the calculator and we upgrade it), or supplying a complete calculator (we do supply a suitable HP41c calculator, already upgraded to CL level, and initialized)


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