Electrical gauges

[Seventh_son]

Hey gang.
New to the forum here. I have a unexplainable affinity for old electrical gauges. Amperes, DC, AC, the vintage ones are gorgeous. So I have accumulated quite a few of them and I was looking to build something to display them.

I'm looking to be able to make them power up or ocassioally fluctuate or spike. You know, make the needle dance. But ideally I would want this to be a lower voltage setting than they are rated for. They are mostly antique so pumping high voltage in to them makes me nervous.

What I'm looking for is a low voltage board that will push the needle and make it dance or pulse. Being that the gauges are set up for various voltages I figured I would just put a appropriate resistor between the two posts to work around what they are set up for. If this won't work let me know.
Does anyone have experience doing what I'm looking to do ?

 

[Terry01]

Neat idea!

There's something about old test gear I love too. I love all old test gear though not just the gauges.
I'm still relatively new to electronics so can't help you sort something out but I have no doubts the guys here will have a way to make them gauges do whatever you want them to,
I'll be keeping an eye on this post for sure!

 

[kellys_eye]

If you remove any shunts (ammeters) then the meters all become 'volt' meters and can be 'equalised' in range by the addition of a suitable series resistor.

Thereafter it's a simple matter to find a number of different varying voltages - these can be from an audio source (diode and capacitor off a speaker) to make a meter 'dance to the music', stepped motion using an R2R ladder and clocking signal (bit more difficult) or some slow-swinging varying DC sources using an op-amp.

Look up some simple audio signal generation circuits and look for circuits that do sub-Hz outputs and you'll find sine, square, saw, ramp etc

You could be adventurous and use an Arduino and drive them using PWM signals.

 

[Bluejets]

The ac ammeters might have moving iron movement.

 

[Alec_t]

Different driving techniques for moving coil and moving iron type meters might be required, as the latter usually need a good bit more current. (Amps rather than microamps).