I told y'all before some of those Chinese radios are liable to burn your
house down.Just like some of those Dell laptop computers.Four out of
five laptop computers are made in Shanghai,China.
cuhulin

Now, cummon guys: you've had some really good advice on this which says
(in a nutshell) that

- charging cells outside the radio with the proper charger is fine
- reverse-charging might be a culprit, but most likely
- the smokin' was just a coincidence

I'm not an international expert on NiCAD v NiMH but I've worked with
these batteries for a couple of decades: they are very similar in many
respects, not least cell voltage which is nominally 1.2v but does rise
to 1.4v+ on charge, and may be c. 1.35 v when you first pop them into
the radio. There is no fundamental difference between a charger for
NiCd v NiMH cells, bar for fact that IN GENERAL you get more mAH
capacity from the latter (assuming same phyical size), so the charger
is usually programmed to wack out more current on it's NiMH setting.
Simple /cheap chargers still rely on a constant current regime which
should not exceed c. 1/10th of the cell's capacity, i.e for 1100mAh,
110mA. Charging at this rate indefinitely should not damage good
quality cells, but they do get warm. Nominal re-charge time will be
12hrs.
More intelligent chargers use higher charge rates to shorten charge
times, but essentially terminate or throttle back charge current when a
certain voltage is reached. There is more opportunity for cell damage
under this regime, but again, as cell voltages are similar, in general
it's OK.

PS
i) memory efffect in NiCd's is not a real-world issue, so don't believe
the marketing hype
ii) anyone who tells you to completely discharge batteried before
re-charging is really saying "please ensure you shorten your battery
life so I can sell you some more"

You can't beat Ray O Vac Alkaline Batteries.That is what I always use.
cuhulin