I have observed that AM operators can be just as culpable as SSB operators when it comes to claiming "ownership" of certain frequencies. I have heard SSB QSO's start up somewhere within the Ghetto while there was no-one using the frequency, and AM'ers actually break into the QSO and advise the offending stations to QSY because they in the "AM Window". To me, that's no different from the 3892 and 3878 groups or the macaroni net claiming ownership of the frequencies they use. Also, I have heard AM operators admit over the air that they knowingly started up only a couple of kc/s away from an ongoing "slopbucket" QSO. When we conduct ourselves over the air in that manner, we are doing exactly the same thing that we complain about the slopbuckets doing.

But by the same token, I refuse to recognise Dead Air Groups. If 3892, 3878, the macaroni, AM Window or any other "owned" frequency happens to be clear, it becomes fair game for anyone to occupy. If I fire up nearby, then the frequency is in use - by me! If you are queued up in front of the service window inside the bank, and you step away to take care of other personal business, you don't return to your old spot when you finish. You go back to the end of the line and start waiting for your turn all over again.

The best way to handle the frequency issue is to open your receiver to a comfortable selectivity, considering band conditions at the time. Then try to find a spot where you hear minimal QRM with the receiver set at that selectivity, and settle in on that frequency. Preferably, you would have some means of adjusting transmitter frequency response so that you could adjust your occupied bandwidth to coincide with your receiver selectivity. No point in transmitting audio out to 8 kc/s (total bandwidth 16 kc/s), when the band is so crowded that no-one is going be listening on a receiver that is set for more than 6 kc/s of selectivity. I have two passive low-pass audio filters in my transmitter audio chain. One gives a gradual cutoff above 5 kc/s, so that everything is gone past 7.5 kc/s. The other has a very sharp cutoff at 3400~. At 3300~ there is less than a dB of attenuation, but at 3500~ not enough signal gets through for the modulation to be detectable on the scope. Those filters are surplus items I picked up at different times, that had accumulated in my junkbox. Similar filters can be found at hamfests and other sources, or even homebuilt. There is quite a bit of data available on active filters that are easy to build. Even a good graphic equaliser could be made to serve. When activity on the band is light, I usually employ the 5 kc/s filter, but when I have to cut the receiver down to 4 or 6 kc/s bandpass to find a clear spot, I try to remember to switch in the 3400~ audio filter. I rarely switch the filter unit out altogether, since my transmitter's response is flat well past 11 kc/s.

Another thing I find irritating, which discourages me from operating in the Ghetto, is that AM stations will sometimes fire up within 4 or 5 kc/s of each other. It is physically impossible to operate that close together without some sideband overlap. Better to spread at least 7 kc/s apart whenever possible. When the band is congested, I can usually copy fairly comfortably when when another AM station with a clean signal is only 5 kc/s away, using the 6 kc mechanical filter, but at only 4 kc/s away, I have to use the 4 or even 3.1 filter, and tune slightly to one side. There is no reason to have to do that when there are unused frequencies nearby.

When I start up on a clear frequency, and after my QSO is firmly established, a SSB group knowingly starts up only 2 kc/s away and then proceeds to gripe about the AM QRM, I am stubborn enough for that to make me feel more determined than ever to stay put. If they can put up with my splatter, I can tolerate theirs. Besides, the AM signal I am trying to copy has two sidebands - sort of a diversity reception situation. Very rarely does intentional SSB QRM make it impossible for me to copy the other station, even on my half-century-old receiver. But I make it a point never to mention the QRM over the air and give the offending operators the satisfaction of knowing that I am even aware of their existence.

Don k4kyv
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