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Where to get a high quality analog DC voltmeter?

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dereksgc:
Hello, first post here. I'm working on a small radio project and I've got the genius idea of using an analog voltmeter as the frequency display. The tuning knob turns a dual potentiometer whose second range forms a voltage divider which is in turn read by the voltmeter to give you the indication of where you are tuned. I got a 15VDC analog meter and I replaced its built in series resistor to turn it into a 3.3V meter (as that is the voltage I'm working with). At first it worked very poorly because I didn't realize that an analog meter will load the 100k voltage divider too much, but that issue has been solved by adding a voltage follower with a high impedance input (currently a RPi pico, hopefully to be replaced by an opamp, that's besides the point now). However my main issue with the meter now is that the needle never seems to settle at the same place. If I go from the 0V marker to the 15V marker on the label and then back to 0V the needle will either land or 0, or at 0.1, 0.2, or below zero, etc. Tapping the meter helps settle the needle which suggests the issue is entirely mechanical inside the meter, which I guess is to be expected from a cheap Chinese "modern" one.

My question is, where in the current age could I get a DC analog voltmeter that would have decent mechanical properties, as in a very well dampened and balanced needle that would at least have a *reasonable* error. I know things like this are to be expected with an analog meter but surely what I have is from the bottom of the barrel and there are meters that are higher quality than this. I'm not really bothered by the scale being non-linear. I've been thinking about buying one of the old analog multimeters as those are bound to have a higher quality mechanical meter as their main display and tuning its series resistance until it behaves like a 3.3V voltmeter, but I may be wrong and I don't want to end up with another borderline useless meter.

Also, I did consider that maybe the meter's poor performance is because it was meant for 15V originally, so I did put in a boost converter to actually drive it with a 15VDC divider and while it did feel a bit more "responsive", the needle not wanting to settle in the same place was still an issue.

TimFox:
Surplus dealers in the US, such as  https://www.surplussales.com/Meters/Index.html
still have decent d'Arsonval meters available, but the good ones (Simpson, Weston, Triplett, etc.) have become expensive (some around $100 USD).

BeBuLamar:
I don't understand what you want to do but why do you need an analog meter? Why a digital won't do? The Radio Shack analog meter with FET front end would give you high impedance input.

Gyro:

--- Quote from: BeBuLamar on June 21, 2024, 03:47:32 pm ---I don't understand what you want to do but why do you need an analog meter? Why a digital won't do? The Radio Shack analog meter with FET front end would give you high impedance input.

--- End quote ---

I suspect that the OP is intending at make a radio receiver. You can't use a simple digital frequency meter (I don't have a reference for the Radio Shack one) because the tuner local oscillator is offset by the IF frequency.

David Hess:
I would look for a taut band meter, and maybe one that has a mirrored scale.  A good d'Arsonval movement meter will also meet your requirements.

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