John and all, Multimedia on HF is just not going to ever happen other than the occasional still picture that we already do now. It is difficult enough now to even get text messages under typical keyboard speed of around 40 + wpm.
Based upon my experience, digital motion images are difficult enough to do on the microwave bands such as with a laptop and WAP along with a medium resolution video camera. I think that the key here is as Danny pointed out that we do this without wires. That is the magic part. The idea that kids don't understand the technologies is a bit overstated. The fact is that most people do not understand technology all that much, but actually I would say that the average student of today may have a bit better grasp of it. They certainly realize that they have to access a cell tower to get their cell phone to work and if you are very far from a tower, you don't have communications. The amount of knowledge to understand current technology is overwhelming compared to when I grew up. As a former audiovisual/computer repair technician, I can say that due to manufacturing efficiencies of today, it is frequently less expensive to replace an entire assembly rather than repair one part of it as we used to do. Thirty years ago it was routine to replace the 1/4" phone plug on a pair of $20 headsets. That has not been economically possible to do for some years now as the repair charge would exceed the replacement cost. Same thing at the board level for moderate cost equipment. As one one of my technicians used to point out, it would be hard to imagine anything more complicated than a VCR with the merging of electronics and mechanical parts to be sold for less money. And yet the prices kept going lower and lower and eventually VCR's were pretty much non repairable item too, even for what most of us would consider a minor repair. What I would like to see the digital mode developers concentrate on is having the most robust mode possible that can get through difficult conditions with perfect copy and do it with adequate keyboarding speed. We don't have many modes that can do that except for perhaps PSKmail which only is available on Linux OS at this time and that is using PSK which has its limits under difficult conditions. Having a mode that can scale to conditions would also be very nice to have and we should always keep emergency needs in the back of our minds, even if it is not the driving force. Because of the drastically reduced bandwidth for Data/RTTY/Text on 80 meters here in the U.S. and perhaps more of that on the way for other bands, depending upon pending FCC decisions, it is my view that we need to keep our bandwidths as narrow as we can. Certainly, good radio amateur practice would lean toward 500 Hz or less. You should only exceed that when you have some unusual conditions, the bands are empty from other users, or you have emergency traffic. Based upon my recent experience with 160 meters, even MFSK16 and DominoEX have their limits, and that is under fairly good conditions in the winter period of the northern hemisphere with low QRN. Low power, modest antennas, still make digital modes a challenge at times with normal keyboard speeds. 73, Rick, KV9U John Champa wrote: > >Not just for text messages....think multimedia: pics, still and motion. >Sound - high quality. etc. >Kids don't understand a phone that doesn't take pics, and soon has an MP3 >player built-in too (HI). > >73, John - K8OCL > > > >
