The single-letter CW channel markers have been noted all over the HF bands for decades. Many years ago, various stations repeating a single CW letter could be found. These have all but disappeared, although there are a few "P" markers left. These signals have been found to be operated by the Russian Navy to mark channels used for RTTY transmissions. After listening to one for some time, you may hear one sending "UMS UMS UMS" and a string of numbers, which would be followed by a RTTY transmission that consists of 5F groups. UMS is an ITU-allocated callsign for Murmansk Radio.

Similar to the channel markers are the single-letter cluster beacons. Cluster beacons are several different stations close together in frequency repeating a single CW letter. These beacon clusters may be used for propagation beacons as opposed to channel markers. In all the years these clusters have been heard, no traffic has ever been noticed as with the regular channel markers. Also, with the signals being so close together, it would be very hard to send traffic with one station without interfering with the others. Cluster beacons are still around, although mainly heard in Europe. They can be heard on 3594, 4557, 5154, 7039, 8495, 10872, 13635, 17015, & 20991. Normally, a C, D, and S are heard grouped together, each letter sent at a different speed.

For several years, European listeners have been familiar with the "buzzer" found on 4625 kHz. This station consists of an AM carrier that repeats a buzz every second or so. At the top of the hour, an alternating two-tone buzz is sent for about a minute, at which the intermittent buzz returns. This station has been DF'ed to an area in the Ukraine in Russia. This station transmitted for several years sending nothing but the buzz until the 24th of December 1997. According to the ENIGMA newsletter, at 2145 the buzzing stopped and was replaced by a series of beeps. These continued until 2202 when various announcements were made in Russian using the same male voice used for the Russian counting stations. This was replaced by (possibly) place names and two 4F groups. The whole thing was repeated, and then three tones were sent which were replaced by the beeping, which were soon replaced by the buzzing. No other messages have been heard since.

Also in Europe, on 3757 kHz, there is a beeper that continuously sends a beep, almost one per second, 24 hours a day. No explanation has ever been found.

Here in the states, on 1740 kHz is a beacon in MCW that transmits "IS1HT" around the clock. This beacon was first noticed in December of last year and has been heard continuously since. It has been rumored that this beacon is located on an oil rig off the coast of Texas. It has also been theorized that this beacon may also be connected to an illegal drift net somewhere in the Atlantic Ocean. The signal is usually S9 at my inland location, so I don't think that this explanation is plausible, especially since the beacon has been transmitting for over three months at such strong levels. This signal has been heard with good levels all over North America.

On 6801 kHz on at least three different occasions I have heard a two-tone beeping signal. This signal consists of a rising tone followed by a falling tone, sounding like "bedeep, bedoop." It also ID's in CW about every 15 minutes with the callsign KGD34. This callsign is allocated to a state highway department, but I doubt that is its purpose. Only more monitoring will shed light on this station. 6802 kHz is used by some of the counting stations.

That's all for this month. If you have any information on any of these mystery beacons, please get in touch with me at one of the addresses at the top of the page.