HP21 Are replacement ICs available?

[elanman99]

A old friend has had an HP41 from new and after not using it for the last 20 years tried to operate with the charger but without the batteries present. My understanding is that this damages the main IC at least.

I have searched on this forum without success to see if anyone has cloned the IC's. Am I correct in assuming that the only repair method is to find a scrap calculator (with a different fault) to make one good machine out of two faulty ones?

Ian

[Steve Simpkin]

Yes, there are several options.
First there is Panamatik's replacement ACT chip to repair a damaged Woodstock series calculator.
http://www.panamatik.de/html/hp_calculat...r_kit.html

Also check out Panamatik's "Woodstock Low Power" upgrade board. This can emulate a number of HP calculator models.
http://www.panamatik.de/html/hp_low_power.html

[BruceH]

Also, José at TheCalculatorStore has done a number of conversions of 41's into 41CLs and, in some cases, the original machines were fully functional -- meaning that he has a number of working, original circuit boards for sale.

See this link (remember to choose C, CV or CX in the product type drop down).

He offers an install service as well.