Using battery power to go off the City's power grid

@jollygreenaudiophile2 mentioned a flywheel type system. Just in case some of you wanted to take a look at this type of energy storage system, here's one that I'm aware of (BTW, you can click on the link on the right hand side for a tutorial):

https://vyconenergy.com/products/ups/vdc-products/

I believe these are mainly used in data centers (and other broadcast applications) to cover the building load, while a generator is ramping up to full voltage, which will then take over the building load. I've never used one, or been part of a facility that had one, but it looks like they can take the place of many UPS'.

When you're really serious about power quality:

Fluke 43B/003 Power Quality Analyzer

Even though this model is now discontinued, you can still find them used on ebay. This unit will display the 60 Hz waveform (in addition to many other things), AND, give you a THD figure. With this meter (I've had one in the past), you might be surprised to find out that your home/apartment/condo utilityAC power is cleaner than you think it is. As many of you are already aware, AC line THD is a good indication of how clean your power is. 

Here's another picture of the Fluke 43B:

Fluke 43B

ricevs,

Here's a perspective on how stupid audio expenditures can be.  Is $2K a trivial amount of money for an audio item that you cannot try before you buy?  NO.  If you buy it after your own listening for a week when you are working with a reputable local dealer, and you like the improvement in the sound, then it is worth every penny, even if you spent $10K.  

But $1K buys a medium intensity PEMF (pulsed electromagnetic field) unit which can be used for numerous health problems.  $10K buys a powerful PEMF unit which can heal major neurological diseases like Parkinson's, Alzheimer's, chronic fatigue, cardiac disease, prostate enlargement and others for which mainstream medicine merely uses drugs and invasive procedures.  Since I know you are interested in alternative health methods, I think you will be interested in this.  Read the writings of Dr. William Pawluk, a major expert in this field.  Look at his site drpawluk (dot) com.  

Wanna be happy?  That comes from achieving the best health and well being possible, which is much more valuable than fleeting audiophile satisfaction.  Most sane people who have good but not perfect health are happy, but many audiophiles who are seeking perfection are never happy.  You can have both, and it is necessary to have a perspective on what is really important so you can justify whatever money you spend on both pursuits.

That station’s radio tower is a couple miles away so fairly close. Interesting that particular RF goes away when on battery power. I assume my house wiring is acting like an big antennae. I just tried it in a few kitchen outlets and got great radio reception there too! haha

For $40 the Entech is enough for now. The Fluke analyzers, even used ones, are over $500. Good inverters have THD of less than 3%. The voluntary THD limit for US voltage is 5%. So, that might explain partially the result here. But, I agree we must listen to music and not just rely on a cheap Entech or expensive Fluke analyzer.  Measurements are a tool not a result.

https://electrical-engineering-portal.com/essential-basics-of-total-harmonic-distortion