The set appeared completely dead and wouldn't power up, even though I tried two freshly charged batteries.
It turned out that a screw had worked loose, and it had ended up being lodged between the +24V battery input terminal and the chassis.
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| PRC320 main PCB, with LSB modification installed |
The offending screw was one of the PCB securing screws which are identified with a green circle on the PCB silkscreen. Its now back in place, centre left of the photo above, and secured with a dab of the wife's red nail varnish.
The little white PCB in the photo above is the LSB modification that I recently fitted. I might detail this in a blog some other time.
If you open up one of these sets yourself it would be a good idea to check all the screws for tightness. Quite a few were loose in mine, along with the nuts securing the BNC sockets on the rear panel.
I later discovered that the dead short had taken out both of the batteries. It appears that they have an internal fuse (probably a good idea if one is going to put a dead short across a large pack of NiCd cells) but unfortunately it is buried deep between the cells where it is inaccessible.
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| Clansman 24V 4Ah NiCd battery |
The battery packs were the later all plastic types and arent meant to be opened, but I was able to prise the bottom off of one of them. I exposed the bottom layer of cells by digging out some of the foam that surrounds them, but I didn't think I would get any further without damaging either the cells or the plastic case.
The thin red and black wires in the centre of the pack are from one of the temperature sensors used by the charger.
I've still got one good battery pack left. That should keep me going for now, but in the longer term I'll either have to buy some more, or come up with and alternative form of battery.
Keep listening!
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