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01/17/2018 - Figuring out how to power this

A project log for Sinclair Scientific Calculator Emulator

A register level TMS0805 CPU emulator on an Arduino Nano runs the original 320 instruction calculator program. A custom PCB houses it all.

arduino-enigmaArduino Enigma 04/13/2018 at 04:431 Comment

Initially, a 9V connector was attached to the emulator. By attaching another 9V connector to different battery holders on hand, it was determined that as little as 3 AAA batteries would make it work. Since the original calculator uses 4 AAA batteries, and the holder fits underneath the calculator, I settled on 4 AAA batteries.

Next was an endurance test. The calculator was powered on and left to drain the batteries, 40 hours later, the drained batteries were measured to provide 3.54V. I am very pleased with this result. A new set of batteries will provide around 6V, for the Arduino power regulator to work all the way down to 3.54V is an excellent result. It begins to look like this will be a viable product. 

The power consumption is approximately 40mA:

Standoffs are just #4 screws for the moment, later we will try to find plastic standoffs:

Everything mounted, the battery pack is attached with velcro that has been glued to the calculator:

Time for a quick instagram post:

https://www.instagram.com/p/BeCcECHHwvd/

Discussions

esey.ziad wrote 12/23/2020 at 06:10 point

9V connector is a useful electronic instrument that can easily solve out mathematical sums in just a few moments. I have read its specs well in this blog and read much sorcerous information about this device so thank you so much for sharing it here. Well, I would like to read uk edubirdie review before hiring essay websites to write me an essay on this topic online.

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