17 years ago
(A) The preamble
I have a small piece of kit which, according to the rather inadequte
information on the pack (no instructions !), is rated at 50mW.
It's 30 years since I took physics in high school, so please bear with
me. IIRC, the relevant equation is as follows:
W = V x A
The kit runs off of a standard 9V battery, so to my simple brain, this
means that it draws a current of 5.56mA (0.05W / 9V = 0.0056mA).
Checking out the various power adapters in my local hardware store, I
can find ones which convert AC input to DC output at 9V with a range of
current values (from 300mA up to 1.0A).
(B) The question
Can I buy any adapter which outputs a current of at least 6mA at 9V and
be sure that my piece of kits is going to (1) work and (2) not get
Thanks in advance for your help