Whats a good economical way to test the electricity on a circuit?

Now that you know your VAC is "Dirty", what you gonna do about it?

I have a good supply, very seldom have outages, very seldom have brownouts, and we haven't had spikes or over voltage for over 30 years.
PG&E went from 8k lines to 20k lines, 35 years ago. A lot of problems went away. Constant Power supplies issues, all around us.

PC especially use to lose their power supplies. One in maybe in 30 years now, from 1 a year. You had to run a PS backup, if you were running a server...

We have smart meters, now too. There is a lot more information there than you might think..

What do you as an owner of expensive equipment, do to protect your gear?

I use something that maintains, the voltage at 120 VAC on the button.
Surge protection, filters above 40 khz, and 20khz. Good copper inlets and outlets on the device. The lowest noise level I can achieve (hum). The quickest response time in the event there is a problem.

There is a few more features, but maintaining the voltage, is one of the best things you can do to increase gear life. Mine cost 300.00 usd or close, and about 6-10 dollars in stuff to quiet the mechanical hum, to practically zip...

Regards

I don't think smart meters are bad, I think they collect a lot of information and STOP, meter readers in their tracks. I really think that is what it's all about. Smart meters cost a LOT of folks their jobs and as a results few EVER come by to check.. That leaves a simple visual inspection of your equipment, unattended.

500.00 meter. 100,000.00 (with H/W and retirement package) per year employee. LOL

Again, you already know it's dirty, and needs maintenance. 300.00 usd and you don't have to check or worry. It checks for you in Milliseconds and responds in milliseconds.. Mine tell me what they are doing, My server monitors the, backup system for the server its self, and any parameter I want to monitor. Hi/Low voltage peak, amps drawn, interruptions, time stamp, WiFi reboot or shutdown...

Most laptops can monitor all that stuff, if you want...Can't fix it though...

Regards