many NiCd chargers use a temp sensor to determine
a full charge, and that will kill NiMH.

** Utter nonsense.

Temp detection is the MAIN way of detecting the end point
when charging NiMH cells.

The PROBLEM comes with NiCd chargers that use VOLTAGE
peak detection - cos NiMH cells never drop voltage like NiCds do.

Sorry, Phil, you've got it backwards.

NiMH cells can show a meaningful voltage drop at the end of charge. In
general, the harder the cell is charged, the greater the drop.

If you can place a thermistor on or near the NiMH cell, detecting the
temperature rise is usually the easiest and cheapest way to terminate
charge. This is particularly true if you're not hitting the cell hard and
don't have a big enough minus delta V to reliably detect.

Chargers that use voltage detection usually also use temperature detection,
as a belt-and-suspenders safety feature. One exception is the MAHA C9000
which uses only delta V (as far as I can tell), because it's hard to read
the cell's temperature through the plastic base of the charger.