33e/c corrosion



#3

I recently had to repair my 33c. The display was intermittent and usually showed a low battery display with fresh batts. Turned out to be severe corrosion on the backside of the battery terminal PCB, the charging contacts (foil was peeling, blue fuzzies everywhere), and all inside the nasty little brown film with embedded conductors (hate those things!). I rewired the batt contacts to the small PCB held in the black plastic frame with thin 30# wire, soldered in place. All is well now.

From reading the posts here (not an easy thing as the search function is cumbersome), it appears the 33 is plagued with corrosion problems. Anyone know if there is a reason for it? All I can say is that my 33C was a "casual use" machine kept in a desk drawer. All my older HPs (woodstocks,classics,topcats,etc.) are kept in a sealed cabinet sans batts with dessicant bricks. And no signs of corrosion on any of them.

-JG


#4

Hi John, glad you got the corrosion problem fixed-up and the unit is working.

My best thoughts on spice calculators are here:

http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/articles.cgi?read=361

It's not an exact match, but does discuss ways that the machines can be permanently degraded, and tips to try to avoid fatal problems...


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