Quote from: TheButterZone on July 24, 2014, 02:24:50 AM

Quote from: matthewh3 on July 24, 2014, 01:49:04 AM

You'd need about 2kbps to download seven 1MB blocks an hour. That's a lot of bandwidth 24/7/365 on a global HF network. I think the Bitsat project and the use of UHF and SHF for a lot more relative bandwidth is the best solution for a global wireless network - https://bitcointalk.org/index.php?topic=334701.0

How would http://www.short-wave.info/ stations work for 2kbps?

Quote

https://en.wikipedia.org/wiki/Q15X25

Q15X25 is a digital signal processor-intensive mode designed to pass AX.25 packets on HF with speed and reliability much greater than traditional HF ARQ modems. It uses 15 QPSK modulated carriers separated by 125 Hertz, each modulated at 83.333 baud. Q15X25 uses forward error correction (FEC), and like MT63, uses time- and frequency-interleaving in order to avoid most error sources. The raw transmission data rate is typically 2500 bit/s.

So 6.67 minutes to download a 1MB block at 2.5kbps. You'd need to operate on two channels so that you had a 2.5kbps receive and 2.5kbps transmit at the same time.