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Messages - Josh

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16
S9 with lovely audio, death cab for cutie track @ 2356z.

17
Something I noted on Zekeys sig a few seconds of delay and an echo, I put it off to pirate audio equipment tastes, but right now on a HAM sig from Barcelona on 7193 lsb there is a noticeable echo, mebbe delayed echo?
https://www.mn.uio.no/fysikk/english/people/aca/sverre/articles/lde.html
https://en.wikipedia.org/wiki/Long_delayed_echo#:~:text=Long%20delayed%20echoes%20(LDEs)%20are,number%20of%20proposed%20scientific%20origins.

18
S3 with a clean goodbye ruby tuesday, 2229Z

19
S6/9 in sw Indiana 2221Z, modulation seems weak compared to carrier.

20
Equipment / Re: Can an antenna work while laying on the ground?
« on: March 31, 2023, 2219 UTC »
One might be able to roll out a directional ground rhombic, orient the antennae so it has a pointy end towards the region of interest, add a variable resistor of a few hundred ohms there, and feed it at the opposite end. A balun of a few hundred ohms to 50 ohms at the feedpoint and tweak the resistor to get the best front to back.

21
Utility / Re: CIS Navy on HF
« on: March 31, 2023, 2203 UTC »
Nice logs gents, 13558 Kaliningrad is just now (3303Z 31MAR23) finishing opchat fsk cw and going into T600 traffic.

And a decoder of sorts for various modes;
https://github.com/IanWraith/Rivet

22
Equipment / Re: Can an antenna work while laying on the ground?
« on: March 25, 2023, 1910 UTC »
Some HAM antenna books have given details on subsurface antennas for hf. One of the more effective setups was simply remove the outer shield from some rg8, waterproof the ends and center connector and bury it about 3 inches below. Another that comes to mind was an antenna laid out in a horizontal mine shaft in the American sw, worked great on the lower bands. The US missile silos have an interesting subsurface vlf antenna array too. Antennas on the surface is like cheating compared to these.

23
22 Meter Band HiFER Beacons / Re: Strong RTTY or similar on 22m
« on: March 19, 2023, 1813 UTC »
A kind soul sent me a 22m ism recording where a CIS 36-50 signal is interfering with a delicate ocean surveillance radar. So there's one source of fsk on ism bands.

24
Utility / Re: CIS Navy on HF
« on: March 19, 2023, 1811 UTC »
A kind soul sent me a recording of a 22m fsk interloper. The signal is CIS 36/50 in this case, with hand sent cw opchat (operator chatter where the radiomen coordinate the setup and takedown of the link in hand sent fsk cw) interspersed with messages.
https://www.sigidwiki.com/wiki/CIS-36-50
The recipient is RDL, or all strategic ie nuclear forces of the Russian federation. This signal is simulkeyed from vlf to vhf on many different freqs so a unit can find the best propagating signal or signals to decode. They don't care where they set up a link, could be HAM bands, could be ISM, stronk soviet signals to all!


What they are doing with these simulkeyed transmissions is fleet broadcast, where there is a constant message stream from HQ to afloat units. Their land based nukes can also tune in. Just like our subs have a buoy packed with antennae and electronics tethered to the sub that cruises along just under the surface where it can pick up our fleet broadcast (USN/NATO uses fsk 50Bd) that keep a constant watch on the broadcast, so does Russia. There are two distinct simulkey nets used by Russia where kremlin directly communicates with afloat units, subverting/bypassing lower commands such as Navy HQ. There are also multiple Russian Navy HQ broadcasts on hf too, from each respective HQ; Vladivistok, Murmansk, Astrakhan, Kaliningrad, etc.

I have a few ideas as to why there are two national command/Kremlin simulkey nets. One is reliability, if one net goes down they still have another at least for a while. Perhaps one net is Russian Navy HQ while the other is direct Kremlin link. Perhaps one is for ssns while the other for ssns. It's fun to consider solutions to the problem.














One Ping Only

25
22 Meter Band HiFER Beacons / Re: Strong RTTY or similar on 22m
« on: March 18, 2023, 1903 UTC »
If you can record some audio we can try to decode it.

26
Amateur Radio / Re: Real time on-the-air spotting/sharing network?
« on: March 17, 2023, 1902 UTC »
This net thingy would be great in say a good weak sig digital mode like robust packet, or even ita2 baudot or ascii would be fun. Heckers even 300Bd packet. Even ale using amd messaging would do.
There are any number of digital suites to use for such, my fav's dm780, but for robust packet you have to download it alone unless you have one of sds high dollar modems;
https://vapn.org/help/robust-packet
DM780 has a lot of modes and I find it to be very stable;
https://www.dxzone.com/dx21563/digital-master-780.html
Use a keyboard to keyboard mode for the net and 110A or similar for file transfers.
I'm going to suggest robust packet for kb2kb and 110A for files but everyone has an opinion.
I have a copy of gtor, a software emulation of GTOR, kantronics answer to pactor that showed a lot more promise than pactor-1 but can't find a online source to direct you to a dl link. GTOR would likely be better for use on older pcs but any pc made in the last 20 years should be serviceable for our porpoises.


27
Utility / KPH 12585.6 BFSK 50/170 Baudot
« on: March 12, 2023, 2008 UTC »
KPH 12585.6 BFSK 50/170 Baudot 2130Z 11MAR23
Weather warnings and other items of interest to mariners.
Their sheet says they tx on 12585.5 but I got them on 12585.6
Weak but the formed filter in the 756 Pro brought it up to clean decode level.
No hard copy as the Icom doesn't provide for that.

Here's their sched;
https://www.radiomarine.org/mrhs-operations

28
Jba music into dj over qrn into sw Indiana 0015Z 03MAR23

29
SDR - Software Defined Radio / Re: RX-888 and graphic board
« on: March 02, 2023, 1749 UTC »
Some considerations on the RX888 and cuda/open cl offloading/cpu time;
One is only certain video card make and model/driver/os can take advantage of gpu offloading in sdrc.
Another is I am pleasantly surprised at Kris' laptop getting as good results as it does with open cl enabled.
Yet another is last I heard the maker of the RX888 is working on a RX999, mebbe that one has a fpga?

I tried some while back with windows 7 on a 4 core cpu and a Nvidia Quadro 2000 gpu and no go on cuda doing the work as the cuda version in the driver, the latest driver made to support the Quadro 2000 in that system, was too old for sdrc so no gpu offload for me.

30
The RF Workbench / Re: Redhat's LULU build attempt
« on: March 02, 2023, 1734 UTC »
Was anyone else thinking rh was gonna drill his hand?

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