|Re: Woodstock collectors: electrical care/prevention tips and practices?|
Message #3 Posted by Vieira, Luiz C. (Brazil) on 28 June 2010, 4:13 p.m.,
in response to message #1 by megarat
I totally agree with the fact that it is not safe charging the batteries while using Woodstocks, but it is harmless to charge the batteries while the regular Woodstocks (not the Continuous Memory type) are switched to OFF. By analyzing their circuits, the AC adapter is isolated from the calculator circuitry for as long as the ON/OFF switch is turned to OFF.
Anyway, some circumstances must be considered:
IF the batteries' contacts fail and you inadvertently switch it to ON, then you may regret that good time...
In the particular case of the HP27, which uses N-MOS circuits that are not compatible with the circuits from other Woodstocks (cannot donate to nor receive from other Woodstocks than another HP27)
The new batteries are different of the ones used some 30 years ago (ampere capacity, charging time/current, etc.) and these oldtimers would not charge these batteries accordingly.
SOOO... just let the batteries 'eat' energy from an outside source. Itīs not worth the risk of burning such fine, rare and expensive HP27īs.
P.S. - BTW, if there is any possible, tinny chance of selling one of these, a friend of mine here in Brazil is dying to have an HP27. Not me, a friend, really!
Edited: 28 June 2010, 4:14 p.m.