What Ever Happened to SCAMP

A few years ago, the WINLINK group was testing a protocol called SCAMP that was soundcard based for those who could not afford the proprietary modem for PACTOR III. Has anyone heard what happened to it?

I thought such a protocol could be useful for VHF ECOMMs especially if it could be used independent of an internet connection.

Seems to me this alternative to WINLINK got buried.



Frank AC3P

 

SCAMP status

I've wondered the same, have searched around, and haven't learned much.

The only thing significant I ran across (last year) was a mention that the developer of SCAMP had run actual on-the-air tests, and had found that the basic modulation scheme didn't work out terribly well under conditions where the channel was subject to selective fading. Since that condition applies on HF fairly frequently, I suspect that the developer may have simply given up the effort.

I wish I could get ahold of the actual modulation specifications used in the old Telebit Trailblazer dialup modems... the ones which first introduced the online community to speeds approaching 19200 bits/second over ordinary dialup lines. These modems used DMT (discrete multitone) modulation, a form of OFDM, and they had the reputation of being able to keep a modem connection on-line via noisy sub-ocean or satellite links (and maintain 9600 bits/second one-way) under conditions when a then-traditional 2400 bit/second V.22bis modem would curl up and die. These modems seemed to be able to work over almost any connection, down to the proverbial "two tin cans and a taut piece of string" and I wonder whether a similar DMT modulation might be made able to work well over HF.

 

It would have replaced expensive modems. Would love to see who the modem company "donates" to in the US.