I have found that I could NOT transmit once. This was during the presence of a strong broadcast band station in the 40M band. I then tested by sounding on top of WWV, a strong SSb signal and a strong AM signal, each time PC-ALE attempted to transmit. Thus , I conclude that I need to be present during any sounding with mouse fingers close to the "pause" button. That said, it is RARE that my ears detect anyone on the ALE suggested sounding frequencies.
On 10/2/07, Rick <[EMAIL PROTECTED]> wrote: > > Have other ALE users found that they could not transmit on a busy > frequency when using PC-ALE? > > (Note: there are no channels on HF amateur radio frequencies except on > 60 meters which prohibits ALE and digital operation of any kind). > > Perhaps I have things set up wrong, but I did a basic test of this > recently and my rig transmitted right on top of another station. This > was a test so I had the power turned to minimum (a watt or two at most). > > 73, > > Rick, KV9U > > > expeditionradio wrote: > > > > A few weeks ago, during the discussion about busy detectors, I > > described some of the different busy detect systems that are currently > > in use by various comm systems. Ham radio ALE operators are some of > > the few on HF who are actually using busy detection on a regular daily > > basis. These are in use with ALE for manual, semi-automatic, and > > automatic operation. > > > > There are two levels of busy detect normally in use with ALE. Both of > > these are available in PCALE and ALE hardware radios: > > > > 1. The first, basic busy detection level for ALE, recognizes ALE > > signals and other digi or CW signals that are mostly sine waves within > > the active signal occupancy range of audio frequencies. This type of > > busy detect is always enabled on ALE systems, and cannot be turned off > > by the operator. It also is used to recognize signals and frequently > > causes the ALE controller to pause while scanning. It prevents > > sounding or calls on top of other signals. If a sounding or scanning > > call transmission is prevented by this detector, the ALE controller > > comes back to the channel and tries again a few minutes later. The > > purpose of this is to prevent signal collisions of any type, and the > > listen time constant is short. > > > > 2. The second type of ALE busy detection is commonly known as "channel > > occupancy check", "polite mode", or "voice detect" and it detects > > signals that are voice-like within, above, and below the active signal > > occupancy range of audio frequencies. It is normally selectable on/off > > by the operator, and the listen time constant is long. It is good to > > enable it whenever a scanning call is being made. If a sounding or > > scanning call transmission is prevented by this detector, the ALE > > controller comes back to the channel and tries again a few minutes > > later. It is mostly used for ALE operation on the voice channels, but > > it has some benefit for normal non-critical or non-emergency > > application on the data channels also. As implemented in many ALE > > systems this super-polite detector tends to falsely prevent ALE > > transmissions very often. It can often be a royal pain in the rear end > > because of the close spacing between signals found on the ham bands. > > > > 73 Bonnie KQ6XA > > . > > > > > > > > > > > > > > > > > > > -- Andy K3UK www.obriensweb.com (QSL via N2RJ)
