On Sun, 9 Jun 2019 09:43:24 +0100, "Jim GM4DHJ ..."
wrote:


"Jim GM4DHJ ..." wrote in message
...

"Another John" wrote in message
...
Hi chaps,

A friend has loaned me his infrared binoculars (Nightfox) for a few
days, but the batteries (Eight! AA) are dead.

I have a supply of rechargeables, but these are NiMH and the
instructions for the device say "please use only alkaline or lithium
batteries".

Surely rechargeables would be OK? Or is there something terrible that
can happen?

Cheers
John

lower voltage so no good ...

...or am I thinking about ni-cads 1.2v ???/??...


Voltage shouldn't be too important within reason. Any device that
stopped working at 1.25 V would "waste" a lot of bettery power with
Alkaline batteries.

Generally outdoor "toys" have to have a bit of resiliance regarding
Volts anyway, simply because low temperatures can drop the applied
Voltage anyway.

A low source impedance can mean disaster for equipment as a lethargic
oscillator will sink a lot of Amps.

AB