Hi Rick and the group just a pennies worth 1) you might consider using fractal image compression schemes (currently used in spy satelites to save time, power, and bandwidth. hunt up a copy of "*Fractals Everywhere*<http://www.amazon.com/gp/product/sitb-next/0120790610/104-8579362-6464706?redirect=true>by michael f. Barnsley for a discussion of the mathmatics involved. I suspect the theory could be applied to any transmission mode and need not be limited to x-25 or 802.11b-g.
On 7/29/06, KV9U <[EMAIL PROTECTED]> wrote: > > A ham about 40 miles away wants to try to make conventional FAX machines > > work on amateur radio VHF/UHF frequencies. Has anyone tried this and had > results that would make it practical? > > The purpose he envisions, is to be able to send any kind of handwritten > notes, such as from medical staff requiring emergency communications. He > has considered that it would be operating on full duplex via two bands, > e.g., 2 meters/440 and use up to the allowable bandwidth on 2. This > would allow for 9k6 bit rates with a 20 KHz signal assuming that a FAX > machine has those kinds of tones. I know that other trellis codes may be > used and that might not be workable, but I am not sure of the exact > tones used by regular telephone FAX machines. > > I also suggested using Multipsk on HF or VHF and working in simplex, but > I have no idea of how well the images would look. A low cost scanner > could be used to scan the image and then convert to bmp file format. > Even huge files I see will go out in 5 minutes or so. But I have no idea > of the quality. > > Any suggestions on whether this is feasible? > > 73, > > Rick, KV9U > > [Non-text portions of this message have been removed] Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
