HP-71B battery drain with no extra RAM or ROM

[hpcalcuser83]

Yes, it is just as Paul described. I opened up the calculator and saw that the battery terminal was broken in half right at the edge of the battery compartment. It looks like the PO flexed the terminal too many times and it finally broke. I fastened some aluminum foil to extend the battery terminal and closed the calculator back up. I tried to turn it on and it would not power on. I removed the battery and connected the AC adapter and the calculator operated fine. I removed the adapter and inserted the batteries. The calculator would not power on. I measured the voltage between all four batteries and got a reading of about 1.7 VDC. This did not seem right so removed all the batteries and measured the voltage as each battery was re-inserted. Everything went fine until I installed the last battery. When the last battery is not making contact with the battery terminal the voltage is about 5.7VDC, but when the battery is making contact then the voltage drops to 1.7 VDC. It looks like some circuit is loading down the battery. This is most likely the source of battery drain. Tomorrow, I will insert a new set of batteries in the calculator and see it will power up.