Fast forward to today, and I am somewhat lumbered with a great stack of old PRC-349 batteries. I cant shift these, because no one wants to buy untested and potentially no use batteries, even when offered at under 50p a go!
So, ive started cycling them all to find which are usable. The first problem I had was making a reliable contact to the batteries, croc clips have a tendency to spring off! Here one of the spare PRC-349 chassis came in handy. Stripped of all other parts and connectors, save the battery terminals, this can be easily connected to the charger by, at present croc clips, but soon by its own dedicated pair of 4mm plugs. The battery then screws in and makes perfect contact just as if being fitted for use in a radio.
|Chassis turned into charge adapter|
After a bit of thought, I realised that in order to check the presence of a battery, the charger must sense current flow to or from it. Now, as for the PRC-350 battery cassette mentioned above, if the terminals are dirty, perhaps the resulting volts drop over the added resistance is causing the problem?
So I took one of the batteries that this morning reported 'connection break', and cleaned the outer surface of the terminals. One connecting to the charger it still reported a fault. So, not just the mating surfaces! So, I removed the terminals
and cleaned away any corrosion and dirt on the fixed terminals of the battery casing, and the underside of the spring terminals
|A very crudded up terminal|