December 29th, 2019
By performing my daily beacon check, I noticed a weak keyed carrier in between the spacing of the F1 signal of DB0UX on 2320.900 MHz. I assumed to see F6DWG/B, which I monitored around the .900 before. But it didn´t take long to find out, that the real signal (mark) was the lower carrier and after a while I learned, it was F5ZNI using reverse F1 keying. Later in the evening the signal increased due to good tropo conditions, as can be seen in the pictures. F5ZNI is the 34th beacon I received in the 13 cm (S) Band
I am always happy about new beacons, but this case is an example, why beacon coordination and using standards is most important. First of all, reverse F1 keying is always bad, as you are used to listen to the upper carrier of the signal. In case there is an unkeyed carrier in between the text, you can easily identify the mark, where to listen. But if there is text keyed nearly all the time, as F5ZNI does, it is rather time consuming until the mark is identified.
The DB0UX signal was strong and the frequency is locked to a reference, while F5ZNI is drifting a little. So it was obvious, that there was a second signal in place. If the french beacon would have been locked to 2320.900 MHz too and would use the standard A1 or F1 keying, there would have been no chance for me to monitor or even to take notice of it.
An excerpt from BEACONSPOT.UK shows the situation on 2320.900 MHz:
|Beacon||Nominal Frequency||Locator||Last Spotted||Last Frequency||Status|
|OZ5SHF||2320.900||JO45VX||2019-08-24||2320.900||Operational on spot date|
|DB0UX||2320.900||JN48FX||2019-12-29||2320.900||Operational on spot date|
|F1ZCC||2320.900||JN08XS||Uncertain - new spot required|
|F5ZNI||2320.904||JN19BQ||2019-12-30||2320.899||Operational on spot date|
So I am urging all beacon keepers to make use of the service provided by the
IARU R1 VHF/UHF/MW Beacon Coordinator. When designing a beacon, please respect chapter 11 “Beacon Requirements” in the IARU-R1 VHF Handbook.