> Andy K3UK wrote: > However, what is the REAL difference between sending > your callsign a few times via ALE , versus picking up > the Mic and asking "is this frequency in use" ?
Hi Andy, I agree Andy, a normal ALE sounding or linking burst is only 10 to 20 seconds duration, and consists of simply callsign ID. HFN pilot stations are using syncronized 10 second duration to minimize this. I, too, suggest that this can hardly be classified as significant interference in anyone's realistic evaluation... when compared to the commonplace (but disruptive) contesting, DX pileups, voice calling, or even spontaneous CQ calls on slow digi modes or slow CW. On the thermometer of "HF interference temperature", ALE is nearly freezing! ALE sounding (station ID) occurs on only one frequency per ham band... in common ALE jargon: "the pilot channel". 90% of all ALE transmissions happen on that pilot channel frequency. ALE operators really have no need or desire to roam through various keyboarding frequencies on each band looking for contacts, CQing, or QRMing QSOs. If the link can't be made on one of the pilot channels, they either give up or wait a little while and try again on the channel. ALE pilot channel frequencies are in the automatic sub-bands (and widely published). ALE doesn't just pop up on keyboarding QSOs unexpectedly. The pilot channels are constantly active with ALE signals throughout the day, worldwide. For those who are not familiar with just how active they are, you can easily view "ALE Channel ZERO" site on the web, with a sample of the ALE activity happening right at this moment: http://hflink.net/qso The system of amateur radio developed ALE is as prime of an example of a ham-friendly 24-hour international HF calling and e-messaging system as anyone can point to. The ALE traffic on a pilot channel is time-multiplexed, with many stations sharing the same frequency slot. Sometimes you can see traffic interleaved with calling. This is quite a highly efficient use of the spectrum. It is likely that anyone who says they are getting their keyboarding QSO clobbered by ALE is intentionally provoking trouble by purposely operating in the automatic sub-band, right on top of the active ALE pilot freq :) The automatic sub-bands are the place on HF where time-division multiplexing and fast ARQ techniques are in active use. If one pauses for a minute, another station may use the frequency during the pause. It's not rude, and it is not QRM. It is normal. It is good time-efficiency in action. The automatic band segments are a stupid place to park a slow keyboarding digi mode... like they say, "If you can't stand the heat, stay out of the kitchen." :) There are other non-ALE automatic stations sharing the same frequencies with ALE pilot channels. Many of these stations also are compatible with time-multiplex operation. Although this results in some QRM or waiting for QSOs, this is generally an acceptable compromise for our shared HF bands. It is part of the nature of operating on HF ham bands, that there are different methods of operation. Some are compatible with each other, some are not. If these concepts are kept in mind, with good intentions, tolerance and friendship, it is possible for harmony to exist among hams on the air. 73 Bonnie KQ6XA
