The HF bands (below 3 and 30 Mhz, also called shortwave) propagate by bouncing of the ionosphere. A major part of amateur radio is using them for intercontinental communication.
That should have said between, not below.
Also, I'll add a link to http://wsprnet.org/drupal/wsprnet/map . Essentially this shows the transmitter and receiver locations for low power beacons, which might give you a sense of what HF propogation looks like. It will vary according to the time of day and solar conditions.
To expand on the other posters, if you can do voice around the world (a few kHz bandwidth) on those frequencies you should very easily be able to do very low bandwidth modulation for data and at reduced power. It would be nice if I could do typing speed but I'd be thrilled with 1 bit per second. Looking around they do have HF packet capable radios but they are quite expensive. I'm going to research those a bit later.
Re:NPR: New Packet Radio
by packet_nerd on Monday March 25, 2019 @05:36PM
(#19486959)
HF digital modes are very common on the shortwave bands. Look up PSK31, etc.. You can convert any SSB (voice) HF radio to digital by connecting it to a computer's audio card.
That is really cool thank you.
Re:NPR: New Packet Radio
by unethical_ban on Monday March 25, 2019 @02:44PM
(#19485439)
Point to point you would have to get into HF or lower frequencies and use the ionosphere. For the hobby of talking long distance as a competition, check https://en.wikipedia.org/wiki/DXing.
Interesting, can you provide any more information? How could you do radio that far? Googling shows it is at least 2,092 miles. What kind of radio can go that far?