HM01 is a new designation to me. What does the HM signify? I just heard that station on 11530 kHz with what sounded like a 5-digit count or a 3/2 count but I am not sure because the signal was weak.
The “HM” in HM01 stands for Hybrid Mode 01, the first Hybrid Mode station recognized by Enigma 2000 as a valid spy numbers station.
Most designations have been in use for years and are pretty straight forward. Voice stations use “E” (English), “G” (German), “S” (Slavic), or “V” (Various, anything voice not covered by E, G, or S). Morse code stations use “M”. Unknown and other transmission that Enigma felt deserved a designation received “X”. And that was the way it was for a few years, but time marches on and technology advances.
The Cubans introduced a digital mode to their numbers schedule. No voice, just digital. Since this signal could be tied to spy numbers (unlike several other suspected signals, such as X06 and XPA) E2K decided to assign it a designation, “SK01”. Although I actually do not know the reason “SK” was selected I suspect it was because the original digital mode used by SK01 was primarily a BPSK, but also several other modes were experimented with. SK01 has since changed to RDFT, and it has used only that for the past 5+ years.
Last year the Cubans started experimenting with a transmission that combined the voice from its V02a station with the RDFT digital data format used by SK01. This station went through a few changes over a period of about 6 months until it stabilized to what is found today. Apparently E2K decided that this was a valid numbers station and that it needed a designation to identify it. They decided on “HM01”, Hybrid Mode 01, as it is a hybrid of the digital SK01 and the voice V02. And yes it does use a five figure group between each data burst.
The Enigma group has always been very deliberate in assigning identifiers. They appear to want to get it right the first time. Several times in the past an identifier has been assigned only to almost immediately have to rescind or delete it. They seem to try to make sure that does not happen again. Several stations in the recent past I would have assigned an identifier to have not yet been designated.
It is nice to get back into the hobby again because I was getting a little burned out with work and school. Best to always put some time aside for some interesting activities like monitoring pirates, clandestines, and numbers. Although there are not as many numbers and clandestines as they were in the 80s and 90s, it is interesting to see them still flourishing in the 21st century. I have not delved too deep yet in this aspect but I was wondering if anyone has attempted to decode any of these messages on a computer. The utilization of one-time use codes is probably still a very effective deterrent against interception even in this age of high technology.
I think there are as many numbers and clandestines today as there were at any one time in the 80’s and 90’s. The difference is who they are sourced from, who they are aimed at, and who is (or can be) listening to them.
In the past Europe was the hot area. Today it is Asia. The majority of the newest numbers stations are Asian. And this presents multiple issues.
A numbers station targeting Asia is quite possibly not going to be heard well in Europe or the majority of the US because of timing and propagation. For example Korean V24 (a long running station, going back to the 70’s, just using it as an example) apparently only transmits between 1200 and 1630 UTC and uses frequencies below 7000 kHz. This frequency range is a night time path range, and there is little overlap when both Europe and Korea, or the US and Korea, are both in dark or just out of darkness. So this station has not very often (by comparison to European oriented stations) been reported.
However, during the same time when V24 was almost unreported in Europe and the US it was well documented and frequently monitored in Japan. But, the European and US based numbers monitors, while sharing info amongst themselves, really had little or no exposure to the Japanese language monitors. Not only was the station hard to hear in Europe or the US, but what was being monitored was being reported in a language the US and European monitors seldom understand.
Following ages are approximate, pulling from memory here and could be a little off. There have been no new G stations designated in about 9 years, no new E stations in 6+ years, and no new S stations in more than 10 years. The most recent designations have been V stations (most recently, V30, 2 years ago), almost all Asian, and several M stations assigned (most recently M97, 2 years ago), also mostly Asian. And more Asian stations have been received but are not well enough understood or documented for E2K to assign a designator. There is one new English station that should probably eventually receive an E2K designation.
As for decoding, yes, computers make things faster and easier, but OTP based codes are still just as secure as they have ever been. On one of my YouTube channel recordings of V24 I have had several claims from apparently different users that someone has decoded the transmission, however I see nothing to support that it was indeed decoded.
T!