Hi all,
in my first post I already discussed a possible cause of the short runtime of the DR100Mk II: high power consumption when using P48. I checked the manual and it lists a maximum power consumption of 4W.
Assuming 2 NiMH AAs with 2.5V, this amounts to 1.6A of current
At this current range, AAs are a bit under-powered...
Since I want to share my hard gained experience of decades of engineering and outdoor recording, here a kind of "executive summary" about batteries and rechargeables:
- care for your batteries. Keep them clean and cool, recharge them regularly and as soon as possible after use. Do not drop them or leave them in the car in the summer.
- keep the battery contacts of your recorder and the contact areas of your batteries clean. Use denatured alcohol and q-tips. we want the lowest contact resistance possible.
- buy quality cells from well-known and reliable sources. Concert tickets and the gas needed to get there are much more expensive than even Lithium AAs.
- If available, choose cells optimized for high current applications (eg "photoflash").
- when building external battery packs, prefer ready-made packs with welded contacts and selected cells. I recommend asking the RC guys. Most battery holders I know are crap, except Bulgin and Keystone ($$$).
Build big. Bigger cells=less resistance and more runtime. P48 is a power hog.
-invest in a good charger. Again, ask the RC guys, there are very good universal (NiCD, NiMH, LiIon, LiPoly, Lead acid) chargers that also can cycle and condition batteries and show charge and discharge capacitances.
If your NiMH cells get hot during charging, it is not a good charger.
I hope this helps a little bit.
Greetings,
Rainer