Posts: 1,788
Threads: 36
Joined: Aug 2007
Yes, the battery contacts in the 19C (and all Woodstocks for that matter) are a weak point in the design. It really helps to put a small wad of aluminium foil in the battery contact holes in the battery pack. HP service people actually made this recommendation to people who complained about 19C battery problems.
The Woodstock battery pack had three different versions. The first had the two cells connected together with only the dual coil spring. This had the possible problem of flakey connections. In reality it was probably the most reliable type.
Next they added a strap welded across the cells. The fixed the flaky contact problem between the cells, but since the cells could no longer move independently, they often made poor contact if the battery contacts in the calculator were not even with each other.
Finally they made the strap between the batteries longer with a little "U" shaped fold in it. The cells could now move somewhat independently, but often not enough to insure good contact.
In wad I trust.