Re: 18 volt vs. 9 volt

Benj <bjacoby@xxxxxxxxxxx> wrote:
On Apr 6, 8:53 pm, Pt <pea...@xxxxxxxxx> wrote:

When you raise the voltage the amperage needed to operate the circuit
becomes less. Batteries last longer.

In most active circuits the amperage drawn is the same regardless of
supply voltage. The limit for supply voltage is usually the voltage
rating of the transistors which is typically higher than 18 volts
which is why many of these active circuits can be boosted to 18v with
no problem. The batteries do last longer however, because you now have
two of them. Duh. But then you also have two to buy and replace.

If the current drawn is the same regardless of whether there are two
batteries or just one, they should last the same amount of time.

What you're saying would be true if the batteries were in parallel and
sharing the current load.

Duh.


.

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