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STANAG-4481F from NSY, back to normal op
(for background read all the post of this topic) After a period during which the signals showed a strange behavior consisting of a 3-bit period (which in some way "simulated" a 50Bd speed), it seems...
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50Bd/300 async 5N1.5 FSK (likely Serbian-Mil)
6374.8 KHz (cf) async 50Bd/300 FSK using 5N1.5 framing, after demodulation:UFBV UFBV UFBV de FNCS FNCS FNCSE9U9 E9U9 E9U9 de FNCS FNCS FNCSZ64G Z64G Z64G de FNCS FNCS FNCSFriends from UDXF group...
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demodulating sync F7B mode transmissions using F7B.exe software
F7B signal, apparently a "classic" MFSK-4My friend cryptomaster coded a program (F7B.exe) for demodulating synchronous F7B, it can be freely used and distributed for the analysis of such signals....
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CIS-14 FSK 100Bd/2000 (CIS 3x100)
Interesting 100Bd/2000 FSK signal spotted on 16059.5 KHz (CF), most likely a Russian Governative transmission. This signal is not a separate one, actually it must be considered as part of the CIS 3x100...
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CIS-81-81 (81-81, Moroz) T-206
Since in the last few weeks I have encountered mostly FSK2 signals (mostly from the East), I decided to take a slightly deeper look at "old" FSK2 modes such as CIS-81-81 and CIS-11 (the latter in a...
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CIS-11 (TORG 10/11)
CIS-11 (also designated as TORG 10/11) is a synchronous, duplex ARQ system requiring separate forward and return links. It's used mainly for aeronautical weather reports in CIS, thus transmissions...
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(yet another) 100Bd/500 FSK-2
4 August 2020 updatesome frequency, same timing, and same 511-bit sequence but the speed has switched to 50Bd (shift remains unchanged, 500Hz).2 August 2020Just to log interesting 100Bd/500 FSK-2...
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Swedish Navy submarine MSK multi-channel broadcast
(For background it might be helpful to read the relevant entries here)Swedish Royal Navy (Swedish: Svenska marinen [1]) uses a broadcast function of STANAG-5030 (1) for communication with its subs in...
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CIS Navy VLF 50Bd/75 FSK (T600 75Hz)
50Bd/75 FSK is the T600 waveform variant utilized by Russian Navy on 18.1 kHz, commonly for submarine communications. Fig. 1 - 50Bd/75 waveformAs seen in CIS 36-50, frames are constructed from data...
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110-220Bd/330 FSK, TMS-430/TC-535 (Swiss Army)
I56578, cryptomasterThis is the well-known Swiss Army 220Bd/330 FSK system consisting of the Telematik-Set 430 (TMS-430) [1] in combination with the cipher device TC-535 [2], the utilized HF...
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48 KBaud OQPSK unid wideband transmissions
This post originates from an email from my friend KE9NS Darrin who noticed a strange transmission around 6.8 MHz with an occupied bandwidth of about 48 KHz. According to his reports, the signal seems...
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S-4538/110A transmissions using (unid) 256-bit IV encryption
While monitoring the 6 MHz band looking for the 48KBd "monster", I ran into some STANAG-4538 "circuit mode service" transmissions on 6898 KHz/USB using the 110A Serial Tone in 2400bps/S mode as traffic...
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3G-ALE synchronous Fast Link Setup (FLSU) failures
Monitoring some US Army MARS frequencies such as 6910 KHz/USB, it happens to see 3G-ALE bursts pairs which are not the usual two-way LQA exchanges, as it happens in 2G-ALE (118-141A), but rather...
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STANAG-4538 to forward 188-220 App.D (SINCGARS) Tx frames to HF
6898 KHz/USB seems to be a good place to catch transmissions which deal with STANAG-4538 3G-HF and COMSEC. After the 256-bit Initialization Vectors encryption, it happened to hear some STANAG-4538...
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KW-46 secured traffic over 188-110A, MHFCS Townsville
Long 110A Serial transmission heard on 6345.4 KHz/usb and used for KW-46/KIV-7 secured fleet broadcast, task usually performed by S4285/S-4481 in NATO Navy.The analysis of the frame structure (Figure...
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two new 50Bd/850 FSK broadcast channels
It seems that the Turkish friends (or "stars and stripes" friends in Turkey) have activated two new 50Bd/850 FSK broadcast channels on 8788.0 and 8792.0 KHz (cf), or likely 8090.0 KHz in ISB mode....
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250Bd/500 FSK embedded channels, likely Ukr nets
Three 250Bd/500 FSK "embedded" channels, 1000 Hz spaced, spotted on 6775.0 KHz (CF) and originating north of Rivne, Ukraine; probably trials or experimental transmissions.Fig. 1 It's to notice that the...
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A not easily classifiable burst waveform
The burst waveform has been monitored on 8118.0 KHz/USB for several days and is part of a multi-mode system which also uses OFDM and MFSK modulations [1]. According to some friends and milcomm...
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a new toy
Just bought (and alreday at home) the compatible Arduino™ Mega 2560 R3 board: a microcontroller board based on the ATmega2560. It has 54 digital I/O pins (14 of which can be used as PWM outputs), 16...
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OFDM 17-tone PSK4 62.5 Bd, "struna" HF (струна)
Heard on 10994.0/USB (10995.5 CF) starting from 1020Z on Twente WebSDR. That "Struna" HF waveform consists of OFDM 17-tone modulation using PSK4 at 62.5 Bd, tones are 62.5 Hz spaced. Struna...
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