I have the Comet PMT-1200 made probably 15 years ago. It has a Ni-Cd battery and a Comet NC-24 charger.
1) Will the new NBH-2428 Ni-Mh battery work in this unit, and
2) can I charge the NBH-2428 with my old charger?
Thank you for your help.
Unfortunately it unclear from Comet's documentation (or lack thereof) if this battery will work in your older unit. NiMh batteries have slightly different output ratings could potentially cause damage to your older PMT-1200.
As for your second question, it is highly doubtful that your older charger will work to charge the newer NiMh battery. Again, the different battery types have different ratings and requirements. Use of your old charger may cause damage to the battery or the charger and could create an extremely hazardous situation.