On Thursday, 21 September 2017 20:22:43 UTC+1, T i m wrote:
On Thu, 21 Sep 2017 11:30:17 -0700 (PDT), "
wrote:

There should be a way to rig a simple resistor to do what you need.

there isn't

I put forward 3 ways that were pretty simple. ;-)

You may have to re-scale the meter, but that should do it.

I might adjust the scale reading from 1 to 5 to 10 to 15 but I didn't
really want to do much more.

Perhaps an adjustable wire-wound resistor that you could tweak until *your* voltage range matched the meter range?

won't get you 10-15v range

The problem with any variable resistor is stability. I could be of for
very fine tuning though.

https://www.alliedelec.com/search/pr...x?SKU=70023692

That's a bigun. ;-)

As a one-off, the cost would not be too excessive.

Ok. Ironically the moving coil meter itself is more expensive than a
digital display or even a wattmeter but I actually want to go old
skool here.

And the meter would be just as 'accurate' as before.

impossible

Ok.

But there should be no reason to get fancy.

No, no reason maybe but if going a 'bit' fancy gives me a better
solution and not for a lot of money or effort I don't mind going for
it. ;-)

It would all depend on how much current is going through the resistor(s).

Hopefully, no more than the 250uA required for FSD Peter. ;-)

Cheers, T i m

Your opamp should do a nice job of protecting the meter, you just need to protect the opamp.


NT