ahh, memories . . .
Posted on 08/21/2013 8:50:45 PM PDT by Errant
bump
sounds good
Crippling the internet might not be the worst thing to happen.
I would think that the patents would be soon to expire. Remember they only patent for 20 years. ECC has been around since at least the end of the 90’s, it can’t have much longer if it hasn’t already gone out of patent.
The wonderful article you linked to is from 1999 and reflects the patents of that time. We are four years beyond that and likely some of the patents have expired. I can’t imagine the most significant of them having more than maybe two or three years left.
Short text data, yes. PDFs or images, no. The narrow bandwidths available in the high-frequency bands don't allow high bit rates. Your home internet connection is probably at least 1 megabit per second. HF digital bit rates are 8-45 bits per second. No, I didn't leave out the "mega" or even "kilo" before "bits".
There are faster modes, but they use acknowledgement by the recipient and retransmission (if necessary) for each data packet. This isn't suited for a broadcast.
The ARRL already does broadcasts like this:
hopefully it can be improved upon
my download speed is 19.95 Mbps and upload is 20.71 Mpbs
for the record
Not in the HF bands. The Nyquist rate puts an upper limit on the symbol rate you can transmit in a bandwidth-limited channel: twice the frequency (in Hertz).
For amateur radio, there is only 500 KHz in the entire 80-meter band, and 300 KHz in the entire 40-meter band. Your fellow hams would probably not appreciate it if you used the entire band for your broadcast.
You could also increase the bit rate by switching to a more complex modulation scheme like 16-QAM (4 bits for each symbol) or even 64-QAM or 256-QAM. But, these are extremely susceptible to noise, and generally are used in closed systems like digital cable and optical fiber.
This is just an idea I had. Even being able to transfer text would be good, the receiver could always generate the PDF or whatever file type is convenient for the local BBS.
I’ve got cash and metals to get me through about 5 or 6 months. And 6 weeks of food.
ahh, memories . . .
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