> John VE5MU wrote: > > The logic of setting this up with an ALE frequency basically > on top of the beacons is competely without merit, > and based on the distorted notion that all hams possess the > very latest in gear to filter out an ALE TX adjacent to > the beacon frequency.
Dear John, The ALE channel is not "on top of" the beacon channel as you suggest. The ALE channel is the next adjacent channel starting 1kHz above the beacon channel. Almost all spectrum management on HF is based upon this type adjacent operation, and the ability for nets or QSOs to operate adjacent to each other without interference. The ALE standards, the IARU frequency coordination, and the beacon network's guard bands all function very well, and there is no interference from ALE to the beacons. John, there really isn't any problem... except in your own mind :) If one doesn't want to operate on that ALE channel or follow the standards, that is their decision. But, please do not begrudge those who follow the estabished frequency coordination and operate with high technical standards without interference. ALE operators have the utmost respect for the NCDXF/IARU Beacon Project network. Generally speaking, many ALE operators tend to be very interested in ionospheric propagation and are avid users of the beacon network more than an average cross section of hams. The NCDXF/IARU Beacon Project network has not asked for more than +/-500Hz of guardband, and this is reflected in the IARU Region bandplans... with the exception of the IARU Region 1 bandplan which has a +/-1kHz guardband. Here is what the NCDXF/IARU Beacon Project network says on its website about the 14100 kHz beacon channel: "If one listens for the beacons with a receiver whose bandwidth is designed for voice reception, the 2.8 kiloHertz bandwidth typical of such receivers will inevitably receive adjacent digital signals as well as the beacons. When this happens, the resulting interference should not be blamed on digital operators so long as their signals are more than 500 Hertz from the beacon frequency." "It is recommended that when you listen to the beacons you use a receiver with a CW IF filter of 500 Hertz or less. Such a narrow IF filter is primarily needed to reduce interference from digital signals on 14100 kiloHertz, but will help you to hear the beacons better on all bands by reducing atmospheric and other noise." So, the NCDXF/IARU Beacon Project network advises the use of a 500Hz receive filter bandwidth. But, in actual practice, it really is not necessary to have the "very latest gear" to filter a CW beacon signal that is more than 1kHz away from the -23dBc edge of an FSK signal. A simple SSB receiver with ordinary bandwidth works fine. Simply tune the receiver properly, or switch to the appropriate sideband. For more information about Beacon Network interference: http://www.ncdxf.org/Beacon/BeaconInterference.html 73---Bonnie KQ6XA .
