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Well, I am glad as a little child that just got a new toy. Today my recently purchased mint-state HP 41CV arrived via the mail, including a card reader with cards and a rechargeable battery-pac with a recharger. The calc I always wanted but which I never could afford when it was still in production. All that for 110 Euros. The calculator naturally works fine, even on the rechargeable pack.
However, the card reader works as well (motor runs) but seems to suffer from a problem common to the 65 and 67 models. There is a greasy substance on the card after passing and sometimes the card gets even stuck in the card reader. I think it is just one of those damn rubber wheels again, I have the same problem with a 67 that I recently obtained. Could anybody confirm my diagnosis?
Then there is something odd about the battery-charger. It is an 82066B, a so called "eurocharger" (that is what can be read on the case). The info on the outer case of the charger also mentions a voltage output of 8VAC. However, when I measure the output voltage directly with an AC voltage meter it gives a voltage of about 14 V (the voltage meter is ok, I did a double check with another meter which also showed the mentioned 14VAC). It seems somewhat strange to me, since it is not plausible that the charger is defect: both calc and accessories were hardly used since the former (1st) owner could not handle the beast very well and soon switched to a Casio.
I read in the archives a little about a similar issue. As I understood it can have something to do with the state of the pack and the pack being insufficiently charged. Besides being also an AC/DC transformer, the pac also acts as a voltage regulator in some versions it was said. Does anybody know some more about this? I would not like to blow up the calcs circuits the first day I have it.

thanks in advance

Yes, the problem is the rubber wheel. You have to change it (more about that in the articles forum). Do not use the reader until you have a new wheel, otherwise the dirt from the wheel spreads in the reader and you have to clean everything.
The charger output without a load might well be about 14 VAC, I will check this at home!

Greetings, Klaus

11,7 V says my Voltmeter, depending on the inner Resistance of the Voltmeter, I would say 14 V are OK!

Greetings, Klaus

Thanks for your response. Is 14V safe to use though, or are there still some risks?

Regards Jan

I don't have a rechargeable pack for my 41, but chargers' voltages are commonly much higher than stated if they're not loaded. I suspect you measured the voltage with no load on it.

14V is safe. An article on TOS about rebuilding the battery pac mentions 14V as output from the charger.

Thanks for the information

best regards
Jan