Radio amateurs don't do it everywhere
Volker Grassmann, DF5AI
November 2, 2001
Starting a CQ call is more than pressing the PTT button on your microphone because you need to find a clear frequency to launch the call. Which one? You may argue this is no significant question because any clear frequency is a good frequency. Obviously, this is not the case in the practice of 6m DXing.
Frequency distribution of amateur radio stations in the 6m band.
The figure displays the frequency distribution of approximately 1.500 amateur radio stations monitored in the 6m band in recent months and years. Don't wonder what reason motivates this type of analysis, it just came in my mind. The bar chart proves that many radio amateurs do not consider any clear frequency a good frequency but multiples of 5 kHz i.e. 50.115 MHz, 50.120 MHz, 50.125 MHz, etc., see the long bars and its equal spacings.
The frequencies 50.130 MHz and 50.140 MHz are very attractive to many 6m operators. Thus, it is no good idea starting CQ calls there because somebody else will probably do the same. On the other hand, 50.147 MHz is suitable for DXing because there is little activity in the range of 50.145 MHz to 50.150 MHz. Many radio amateurs apparently hate 50.139 MHz, so do I because there isn't much to this frequency, from an aesthetical point of view.