That "My TV" part of the title just reminded me of... "I WANT MY MTV"
One of the more popular sayings from the 80's

I get side tracked easily.
And now back to our show!

Just sharing my TV monitor pain.

I've been using my TV as a monitor for many years now.
It has it's advantages and disadvantages like everything.
For me it makes sense, I don't game and most of the media I watch is from the computer.

I've had to make a few adjustments (which are described below)
because my TV is on the other side of the room almost 20 feet away.

First, my eyesight is not improving as I get older and
Second, in certain situations my TV starts balking after no activity.

To resolve these issues, I happily turned to bash.

I hope my eyesight improves next year, but for now, I'll adjust the resolution.
I can increase text size within programs and browsers, but not usually the menu bars etc..
so I adjust the overall resolution.
Here is my script:

if you run xrandr with no arguments, it will list the display name, which in my case was HDMI1

Now for the lack of screen activity.
Here is my script:

I combined them into a startup script which I ran after my window manager came up,
but I'm wayyyyy to lazy for that so I recently added these scripts to my .xinitrc file.
If you're not familiar with this file, I boot up into a shell, login and run startx
which launches my X environment and my .xinitrc script.

In order for all 3 lines to execute, I used "&" to daemonize my scripts into the background
and continue to execute the .xinitrc file which ends by launching my window manager.

I WANT MY MTV AS A MONITOR!!!

Now for the lack of screen activity.

I have little HP Stream 11 which blanks the screen after ten minutes of inactivity. Annoyingly, about half the time it fails to recover the screen when the next keyboard or mouse activity comes along. The machine doesn't crash (I can log in via ssh and fix it if I'm at home) but trying to get to the console (ctrl-alt-F1) doesn't work and blindly opening a terminal (ctrl-alt-enter) to blindly pkill Xorg doesn't work either so when I'm away from home (which is almost the only time I use this machine I just need it to never go blank.

Initially, I used a script much like yours and it worked. I toyed with the idea of moving the mouse in geometric patterns just for the fun of it but abandoned that when I realized that I don't want the mouse wandering around the screen when I -am- trying to use it. The answer, for me, was to use xprintidle to get the idle time in milliseconds, then only invoke xdotool mousemove when the idle time exceeds nine minutes. And I'm still just tweaking the mouse, not moving it in geometric patterns.

The answer, for me, was to use xprintidle to get the idle time in milliseconds, then only invoke xdotool mousemove when the idle time exceeds nine minutes. And I'm still just tweaking the mouse, not moving it in geometric patterns.

@MikeRocor Thanks for that awesome suggestion!
I'm jumping right on it and I'll share the journey....

Let's download the source... isn't open-source cool

I chose the ZIP file.

The instructions look easy enough, he suggests using meson so I'll have to download it along with the dependencies listed.

So far so good...
Let's check the version, not because they matter, but to see if it installed correctly... looks good

I created a "dev" folder in my home to unziop the file.

OK, let's build it...

Now let's install...

Looks like success, let's check the version and try it out...

I'll have to experiment a little and work it into a script.
Thanks again @MikeRocor

I'll revisit this thread when I work xprintidle into a new activity script.
Same Bat Time, Same Bat Channel...

I have a wireless HDMI adapter which works pretty well. The transmitter plugs in to the HDMI port on the computer, and the receiver connects to an HDMI port on the TV, and no cable is needed. I can use the TV remote to switch between HDMI inputs as desired, and the wireless connection stays alive as long as the transmitter is powered in the HDMI port. It wasn't expensive, probably cheaper than a long HDMI cable, and wireless is far more convenient. I've never needed to do anything other than plug them in.

@deb_user Thank You for your suggestion!
I've been using that technology for a long time now, but at certain times the TV balks due to inactivity.

I'm thinking of a 30 foot thick HDMI cable across the floor.
My cats would either stay out of the room or attack it.
Either way it would be a very funny scene - that made my day @deb_user thanks.

Update:

After testing, the xprintidle works flawlessly.
Now I know a little bit more about how screensavers work.

I modified the tv_active.sh script and it's been running all day.

Thanks for the great ideas!
This is why I'm on the forum, to share whatever I can and benefit from others sharing.
Community!!

just reminded me of... "I WANT MY MTV"
One of the more popular sayings from the 80's

Dire Straits, the Knoffler brothers and others. Love that song. Money for Nothing.

One of my 2 monitors used to be a TV. Ditto for my wife's monitor. Her father gave us his old big screen TV, and now an older DTV is her monitor.

I'm thinking of a 30 foot thick HDMI cable across the floor.

That seems like an extremely thick cable.

same, except I'm typically around 4 or 5 feet from my TV (acting as a monitor). I use usb extension cables for mouse & keyboard.

Yes that is thick

I'm thinking of a 30 foot thick HDMI cable across the floor.

I forgot to add the comma, but it was a much more entertaining post without it!

I haven't used a wired keyboard or mouse for at least a decade.

There are a number of "streaming sticks" on the market, including Google's chromecast, Amazon's Fire Stick, and others. I've been using chromecasts for years, mostly to cast from my phone, but also from the computer. The HDMI wireless setup I referenced above works well, about as well as an HDMI cable, but far more versatile and convenient. The receiver needs power through a USB-C cable, but that's easy enough. Most TVs have a USB port which will supply plenty of power, and if not any phone charger will do the job. For awhile I had it set up on my server, in a somewhat inconvenient location, but with the HDMI wireless, plus wireless keyboard and mouse, I could use the big TV as a monitor for it. I no longer do that, because I'm now using a different computer for the server, with no DE, just ssh. GUIs are over-rated for some tasks.

I bought my cousin's old TV to use as a monitor. It's from back in the day when 1080p was "full HD." Given its age, the color saturation levels, and how warm it gets, I think it's an old plasma screen.

I should probably find something cheaper to run.

I haven't used a wired keyboard or mouse for at least a decade.

Circa 2012 for me. I don't miss those days. Wireless units last years on a single set of batteries; so long that I forget what size they take. And being able to take one keyboard and mouse set and hook them up to multiple computers means you don't have to hassle with keeping track of what is paired with which.

It looks like they do make some small wireless monitors. They look like they're mostly aimed at industrial solutions, but finding information about them isn't easy.

I wonder if terms like "rugged," "hospitality," "maintenance," "facility," "contractor" or similar might help cull unwanted results.

@deb_user Thank You for your suggestion!
I've been using that technology for a long time now, but at certain times the TV balks due to inactivity.

That may be due to a setting on the TV. Have you looked through the settings carefully? It may revert to a different input after inactivity on the one with the computer connection.

With gsettings you can always query and set a variable the same way. So you can do
gsettings get org.gnome.desktop.session idle-delay
to get the active setting, and then use set for a different one.

It is always a user setting. Gsettings is from the Glib project, originating from the GTK toolkit. So, if your non-GNOME desktop uses it, it is likely that an idle-delay is configurable for it too. You could do something like

gsettings list-recursively | grep -i 'idle-delay'

to search for it.

I'll probably have some time to do a bit of maintenance on that machine this evening so I'll try that out and see if it does the trick. The iffy part is that the video recovery failure doesn't always happen, so it will take a while before I'm confident it is solved. The current "soultion" is really just a work-around since it just prevents the thing being idle, but I know it's working. I suppose this new approach, while it prevents the screen shut-down-on-idle without preventing "idleness", still won't prevent the screen failing to come back if the shut-down -does- occur for some other reason.