Where can I buy a large analogue meter?

On a sunny day (Fri, 15 Apr 2022 09:08:46 +0100) it happened "Commander Kinsey" snipped-for-privacy@nospam.com wrote in snipped-for-privacy@ryzen.lan:

Just for the sake of argument, and because posting to DIY and electronics.design driving an RC servo is not that hard:

You may want to use a PIC with ADC so you can measure voltage I use a lot of 18F14K22 in all sort of projects

Not that they are the same, but cell phones used to charge slowly, that tech is rapidly advancing. All phones have some form of quick charging now, I can fully charge mine in 1:30. And that's at 16W, the highest I've been able to achieve, though the phone specs claim 25W. There are phones available here that do 65W, in China 100W.

Clearly the units have to be converted.

Never played with those things. I only have 100 cores of Window PC.

No. It can be done entirely in analogue. Servo motor controls a potentiometer that balances out a potential divider to match the incoming unknown voltage. Classic A level physics experiment.

Put a needle on the shaft of the pot and you are done!

It is how all servos were done once upon a time in the pre digital age.

Obviously you have never seen the evolution of cars, airplanes, electronics and the advances that can be made in five years.

Cars today no longer have to be hand cranked to start and the top models even have heaters in them. Amazing the progress they made.

use a regular size meter modified to have a glass back with an overhead projector.

On a sunny day (Fri, 15 Apr 2022 13:12:19 +0100) it happened Martin Brown <'''newspam'''@nonad.co.uk> wrote in <t3bnf4$17oc$ snipped-for-privacy@gioia.aioe.org>:

This is about RC servos, easy to obtain anywhere at low cost for small ones,

Those servos have a chip to drive the motor and a potmeter feeds back to it as you described. The RC protocol is almost universal. Maybe you could hack one but then you need to design the drive electronics and comparator. Remember servo turns both ways... Would be a lot more work. Else SHOW us what you have.

To make PWM from DC volts you'll need a ramp generator and a comparator. The ramp doen't need ot be perfectly linear, you can adjust the scale markings.

My question is - how much does it affect range ? ... .. 90 degree summer driving / - 20 C. winter driving .. plus wide open driveway parking - no garage. Where I live, 3 months are A/C ; 5 months are wintery ;

- those conditions would likely cause some increase in charging cycles < per year or per km of driving > which would reduce the life of the battery ... how much in real world ? me wonders. John T.

Obviously you haven't .

Nothing much has changed in any of those fields - they are pretty mature tech.

Nor have they been for the last 60 years

and the top models

I remember heaters in the 1950 cars

Amazing the progress they made.

Amazing the delusions you suffer from

I don't understand why people go into engineering and science. According to you, everything is already invented and will never get better. Nothing can or will be improved.

RC servos are the bomb. I've used them to rotate diffraction gratings in spectrometers.

For applications needing higher performance than a dial meter for demos, you can get Oilite bronze bearings, titanium gears, high speed, and gobs of torque for $150 in onesies.

Cheers

Phil Hobbs

You are atypical.

That's certainly not unique to electric vehicles. There was the Ford Explorer defect that caused a few garage fires (a neighbor had parked outside the garage - didn't help, still set the front of the house on fire).

The numbers can be found with a simple google search. IIRC, the range is reduced by 10 to 17% by the environmental control system (HVAC) depending on the outside temperature.

Coincidentally, I had a conversation this morning with an engineer who works for Ford. He works in image processing; one of the projects he worked on a few years ago enables the backup camera to initiate braking if it sees an obstacle. He actually benefited from this feature on a cloudy, gray day when he was backing up toward a gray car.

My husband gave him an idea for additional features for automatic headlights. He said he'd split his bonus with us if he gets one.

There really is a lot more going on than you realize, TNP.

Yes. And when, on the plant, they have volts they can drive an electronic device that is going to be cheaper, more accurate, have logging and remote transmission capability, be self illuminating, etc etc. And when it stops working they know the volts have stopped too.

As I said, chemical plant still has a use for pressure gauges.