> John VE5MU wrote: > If you specify a VFO frequency, this is a good starting point > for finding the other station. With the number of modes out > that allow tuning the offset, the offset can vary from > under 500hz to 2000hz and still stay within the bandpass > of most rigs.
Hi John, ALE uses fixed audio frequencies and fixed channels. This may not be like the other digital modes you are familiar with, but for ALE, you will find that it is essential. Good ALE ham operation requires a level of operator responsibility, and cooperation above what is needed for some other "modes". Of course, if you want to play with ALE in a non-coordinated way, you don't need to follow the standards :) But, you also don't need to prove to anyone that you can operate ALE anywhere you like, and do whatever you like... we already know that anyone can do that... you won't be the first :) When the early ALE ham operators started using it, we were operating "ad hoc". Everyone was announcing their own channel frequencies, and they were all different. It was chaos. We rapidly found that we were defeating ourselves, and we got organised. Now we have a framework that functions well. Any operator or net can come up on ALE at any time, anywhere in the world, using the ALE standards, and enjoy the full benefits of it. Unlike the other digital modes you are familiar with, ALE transmissions always use fixed audio frequencies. The offset is never variable. The channel frequencies are exact, and good calibration is required. The ALE system ceases to function properly if variable is used. Recently, Patrick has released a test version of Multipsk that includes some ALE functions, the ability to call and decode ALE and its associated protocols, and a new exciting mode of ARQ. Multipsk is the only program that I know of that has variable transmit ALE tones... and the operators who are testing this version should be carefully aware of how they operate on the ALE coordinated channels, be absolutely sure your Multipsk "141A options" are set to FIXED frequency. Bonnie KQ6XA
