Description
This innovative USB-C rechargeable battery pack brings your vintage HP calculator back to life!
Replacement for HP 82120A
I was tired of having to constantly buy new N-Size batteries and was also not satisfied by the amount of charge in the standard rechargeable pack, so I decided to design one to use in my HP-41 series calculators.
UPDATE: I have implemented an improved DC-DC circuit that lowers the unit’s output voltage to ~3.3V when the LiPo battery nears the end of its charge so that the BAT-Annunciator of the calculator is triggered. When the BAT-Annunciator is triggered the battery will run another 20-30 minutes before completely shutting down.
This brand-new, professionally 3D-printed battery pack is specifically designed for HP-41C/CV/CX/CL calculators.
Features:
- USB-C Rechargeable: Ditch the disposable batteries and enjoy the convenience of modern charging. Includes a USB-C cable for easy connection to any USB power source (USB adapter not included).
- Long-lasting Power: Equipped with a high-capacity 1200mAh Li-Po battery, this pack provides around 50 hours of continuous use for your HP-41 calculator.
- Fast Charging: Recharge the battery in approximately 1.5 hours using a USB-C wall adapter (not included).
- Durable Design: Professionally 3D printed in Nylon for a strong and lightweight construction.
- Easy Installation: Simply replace the original battery compartment with this custom-designed pack.
- BAT – Annunciator support: Indication of near empty battery is working
Notes:
- Charging: While the battery can be charged inside the calculator, for optimal lifespan, I recommend removing the pack for charging.
- 3D printed note: The 3D printed case may have slight cosmetic variations due to the printing process. Functionality is not affected.
What’s included:
- 1x USB-C Rechargeable Battery Pack (3D printed in Nylon)
- 1x USB-C Charging Cable
Give your beloved HP-41 calculator a new lease on life with this eco-friendly and convenient rechargeable battery solution!
Please note: This is an aftermarket product not affiliated with Hewlett-Packard.
Compatible models:
- HP-41C
- HP-41CV
- HP-41CX
- HP-41CL
Don’t wait – upgrade your HP-41 calculator today!
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Keijo Salonen FI (verified owner) –
An absolutely perfect power supply for the HP-41CX calculator. A high-quality product that fits perfectly in place. No more need to mess around with separate batteries. Fast delivery and well-packed parcel. I highly recommend it to all true fans of the HP-41C calculators!