With flat earth they wouldn't NEED to bounce off anything.

I don't agree. The air being much clearer up high, it makes more sense to aim the signal upwards with a view to bouncing it off the dome to come back down again. And then there are obstructions on ground level such as mountains that you can't see because they are out of view.

As if... I've lived several places where there is no cell service, no cable, and no satellite tv, even tho there was access to the southern sky.  Now that there are plenty of towers, these spots are fewer, but I actually drive through one for a couple of miles every Sunday where there's no cell service for my tunes.  If there are satellites roaming around upstairs, why can't they reach this area fully open to the sky?  Why do I have to shut off my car radio every Sunday several miles from home because there's no service?  Since satellites don't pass over me for some reason, unless and until an underground cable goes in with a repeater, or a tower goes up, I'll guess I'll have to continue listening to crickets.    

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Just because you have not been able to use satellite services doesn't mean they're not available.
You have to be willing to pay for the service, which isn't cheap because satellites are expensive.
Wealthy subscribers can generally find a service to suit their needs regardless of where on earth they are.
Here are some examples of what you can get if you don't mind spending the bucks.

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Inmarsat

Inmarsat covers most of the world between latitudes 70 S and 70 N, with phone, text, and Internet services, using three “bent pipe” satellites in GEO orbits. Inmarsat works with just one handheld satellite phone – the IsatPhone Pro. Inmarsat does not support any text-only devices. Inmarsat also supports BGAN terminals.

 
Iridium

Iridium covers virtually the entire world, with phone, text, and Internet services, using 66 “space network” satellites in LEO orbits 780 km high. Iridium works with several handheld satellite phones and text-only devices. The US Department of Defense is a major user of Iridium, owning and operating their own ground station in Hawaii. Iridium is prohibited by US laws from operating in Taliban controlled Afghanistan, Cuba, Iran, North Korea, Syria and Sudan.
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Neil posts ads for companies like its proof.

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Those are not ads. Duuuh.
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The source site (if you would dare go there and become informed) is a service for backpackers who want to know about what is available and why it works the way it does.
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Serious backpackers get into some very remote terrain and they like to have a backup communication device if possible.
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You were cited above saying you can't get service THEREFORE satellites don't exist. Which is stupid.
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Are you really that stupid?
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The link for Part 2 above takes you to a site that begins thusly (to view the whole thing you need to subscribe):
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 SOTMR: TWO-WAY SATELLITE COMMUNICATIONS FOR BACKPACKING: PART 2 – SATELLITE PHONES
BY Rex Sanders ON MARCH 26, 2013 STATE OF THE MARKET REPORTS

Satellite phones have been available for decades. The earliest "portable" satellite phones were transported in several suitcases, and required hours of set up time, including unfolding a large dish antenna. Second-generation "briefcase" satellite phones can be set up in a few minutes, but must remain stationary to be used.

Satellite phones practical for lightweight backpacking appeared in 1998 using the Iridium and Globalstar satellite systems, followed by Thuraya, Inmarsat and Terrestar. See Part 1 for a description of these satellite systems.

This Part 2 covers satellite phones suitable for lightweight backpacking. Part 3 covers two-way satellite text-only devices. All the information in this series comes from vendor web sites and online reviews, except for the "Personal experience" sections.

And I'm skeptical that he does what he claims.

Why the skepticism? Because I won't post code here? I linked a perfectly good open source docuмent on the math I was talking about above. Peruse at your leisure. 

For calling it an ad?  No. Official or not, with this* conclusion at the bottom of the page,
Recommended systems for satellite phone or text
The performance of any satellite system is strongly dependent on the devices you use, how you use them, and where you use them. Reviews really compare devices and use cases, not systems. Still, we can compare satellite systems based on design, operations, and available devices.
So in my not-so-humble opinion …
*Best: Iridium

After all the pretty pictures, this whole page winds up being a kind of 'ad' for the Iridium company, over Orbcomm, Terastar and Globestar. (Perhaps the writer works for the company?) It certainly doesn't tell anyone anything about how telecommunications work on a globe.  Posting this in a flat earth discussion is like saying: "since telecommunications work, then the earth must be a globe."  Typical Neil.

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Sour grapes? Can't stand it when you're proven wrong? It's not an ad. It's a review for backpackers' information.
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Of course, if you know more than the reviewer why don't you post it?
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Oh, right, you don't think there ARE any satellites that can do this. You think it's all cell phone towers! 
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I only excerpted parts of the page. If you want to know how the systems work, go to the website.
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I've tried posting information on how satellites work and only got flat-earthers' vitriol and calumny for the effort.
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Now you accuse me of not doing it AGAIN? Why, so you can complain about that too?
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Your shrill, whiny complaining only makes you look worse -- if that's even possible.
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Flat-earthers (and their sympathizers) have nothing reasonable to complain about so they grope at straws.
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You shouldn't worry about it, because it's expected. You gave THEM something to worry about.
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You're as bad as the worst of the trolls here. The fact that you happen to be right in this case doesn't change that.

I don't agree. The air being much clearer up high, it makes more sense to aim the signal upwards with a view to bouncing it off the dome to come back down again. And then there are obstructions on ground level such as mountains that you can't see because they are out of view.

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The problem with that plan is there isn't any "dome."
Sometimes a signal bounces back, sometimes it doesn't.
If a "dome" were there it would always bounce the signal back.
The fact that the signal only bounces SOMETIMES and usually DOESN'T is proof there is no dome.
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