Abordnet

Hi Group - The Stern Lightning I just picked up had some battery corrosion that I have since cleaned up. Now the question - the battery I removed from the board (Stern MPU200) was a 3.6 VDC Nic-Cad rechargable.  I went to Radio Shack (with low hopes) and found that there were actually a lot of 3.6 Volt Nic-Cad batteries that are used for wireless house phones. The only extra information that I found on the new battery is 350mAh - there is no such designation on the old Stern/GE original. I really do not want to hook this up and blow up my gameroom/house/ neighborhood  so can someone please let me know if this replacement will work . . . Thanks, Barry Schiffer

It will depend on the charging circuit. The simplest and cheapest way to charge a NiCad is the C/10 method. This is where the circuit puts a constant current that is one tenth of the Amp-Hour capacity into the battery.  NiCads will tolerate this basically indefinitely.  However, this takes a long time to charge, as much as 16 hours. The alternative is an active type of charge, and there are many types of those.  The initial current is high, but then throttles back when it senses the battery is getting full.  This allows a shorter charge, but if your battery has too small a capacity, it could damage it. If you want, you can send me the schematic, and I will take a look for you. I recommend changing it to alkalines with a blocking diode - that's what I do to all of mine, or the capacitor method would work too (although you need to do 2 5101's vs. 1 on a bally not sure how well that would work). I don't recommend putting the rechargeable ones back in there at all. -scott CARGPB#29

E-mail sent . . . Thanks! Barry Schiffer

Hi Scott - I am seriously considering that alternative - thanks for the recommendation! Barry Schiffer

Just for the record (with many thanks to our resident Rocket Scientist - Edward Cheung), replacing the old GE 3.6 Volt NiCad battery on a Stern MPU200 is easily done. If you want to use rechargable batteries, the wireless phone batteries currenty available from Radio Shack (Nickle-Cadmium 3.6 Volt, 50mAh or higher) are a viable replacement option. Thanks, again, Edward! Barry Schiffer