=20
>   "The nominal voltage of a fresh alkaline cell is 1.5 V."

"nominal" is used to categorise the cell. For example a NiCd
is nominally 1.2V (1.4V when freshly charged), a lead-acid
battery is nominally 12V (13.8V when freshly charged) etc

In the freshly-charged state, naturally they have their greatest
capacity. As Wikipedia notes, the discharge curve depends on
the current drawn. For circuits that draw very small currents
from alkalines the limit is the chemical shelf-life (10+ years)

I think in your situation you really need to measure both the
working voltage and current draw from a set of new batteries

If you want to be a complete anorak and get very involved -

A DMM will give you most of the story but a scope will tell
you if there are any significant pulse current draws. If you
don't see any, you can add resistance to the B+ line until the
tapestry starts failing and look for pulses then. You'll have
some idea of the pulse current by the voltage drop across
the resistor. It might not be terribly accurate but you'll at least
know that demands are being made over and above the static
current, and your PSU will have to cope with that. Usually a
large reservoir capacitor will do. Reckon on about 1000uF
per amp at the minimum

As an example, infra-red transmitters, eg remote controls,
have a reservoir cap local to the LED(s). Remove that and
it doesn't work so good, yet to all intents and purposes the
circuit looks the same to a DMM. That cap is there to supply
the IR pulse demand

Joe
--=20
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