We use this system to power TVs, expecting to power four of them for several hours.  We’re in the United States.

Power Supply parts:

  • Renogy Off Grid Pure-Sine Wave Battery Inverter 500W 12V Input
  • Ginsco 12V Car Cigarette Lighter Dual Socket USB Adapter Charger & Digital Voltmeter with Switch DIY Kit Black#2
  • Vmaxtanks VMAX SLR155 AGM 12v 155ah
  • VMAXTANKS BC1215 15 Amp 12 Volt 7 Stage Heavy Duty Smart Battery Charger & Maintainer
  • Coleman Cable 04644 4-Outlet GFCI Power Strip with 6-Feet Cord, 15-Amp
  • DeWalt DWST33090 15 gallon Contractor Storage Chest On Wheels
  • Harbor Freight cart
  • nuts bolts battery traps

This is about 125 lbs. and requires two people to lift.


  • No automatic alt text available.These double camera straps work well.  An ordinary padded neck strap put a lot of strain on the back/neck – got pretty rough after about  90 minutes, even with breaks.  We were also wondering if a monopod (with strap for stability) would be useful for people who can’t hold any weight.
  • Bolt large picture frame/mirror mounts (like in the photo) to the wall mount holes on the back of the TV, using the exact size screw the TV calls for.  The screws tend to come loose and get lost, so consider thread-locking glue.


  • Insignia 32″ LED 720 Smart TV (needs to be “smart” to run a flashdrive movie off the USB – see bottom for an alternative).  These are 10 lbs.  The 24″ is 7 lbs. and we bought one of those.
  • TV requires a software tweak which requires someone’s Roku account, because out of the box it won’t loop the movies – will play once and stop:

How to tweak the TVs:

Problems – store mode means an annoying menu pops up every few minutes.  Taking it out of store mode means videos don’t loop.  Sometimes the sound comes on.

  1. I turned off store mode in settings
  2. I turned off the sound in settings (we will want it back on for tablings)
    >> It wouldn’t loop videos.  I found this explanation of a private hack that would do that.  So…
  3. I logged TV into my wifi and Roku acct.
    >> Unfortunately it added all our channels to the TV
  4. I installed the private channel USB Media Browser (invitation code KGULU).  I did this under My Account, Add Channel at   I removed all the other channels one by one.  The next time our personal TV updated from Roku it deleted all those channels from our TV, too, unfortunately.  But I can put them back and I shouldn’t need to connect the AR TVs to my acct again.

From the home menu, use the green unlabeled USB icon to run the files.  You must run the file with the Play button, not “OK,” to have it loop.  OK will make it run once.  Pressing Play, it will repeat the whole directory.  There is no option to play only one item, but it won’t go into another directory.  There is a 1 second buffering between files.  FF & REW work.  It played all files and looped back to the beginning of the list.  I also tested with my home wifi off.  It seems that once per day the USB app tries to check for updates, and it gets an error if you’re not in wifi.  It’s OK, you just try again and the app will work.

Because of the above looping behavior, I put stuff we wanted to loop separately into separate directories.  We usually have one TV looping the dairy video so volunteers can always point that out to vegetarians.  This setup runs great for hours with no intervention.

Here are the instructions I wrote for end users:

  • Any remote works with any TV.
  • Turn on the TV using the remote.
  • When it comes to the home screen, arrow to the right to the green USB icon and hit enter.
  • This may give you an error that it can’t connect.  Don’t panic.  Hit the Home button and try again, and it should work the 2nd time.
  • The screen will say CUBE.  That’s the flash drive.  Press OK.
  • Now you will see a list:
    • “Movies” – the root directory, has the 5 or so general meat/dairy/eggs movies.
    • “Dairy” – Dairy directory, has one movie
    • “Eggs” – Egg directory, has one movie
    • “Fur” – Fur directory, has two movies
  • When you’ve selected one of the above and have a movie highlighted, Click the PLAY button.   The player will loop through all the movies in that directory.  The OK button will seem to work work but will not loop.
  • The FF & REW buttons do work.


Something to think about – if you want to get fancier than just looping movies, you can tape a Raspberry Pi to the back of the TV and have it do whatever you want – it’s a tiny computer.  You probably wouldn’t need a “smart” TV, just a USB input that could control the screen.  Or maybe a smartphone could play a movie over USB.