UNID CW at 4870 KHZ

[ultravista]

UNID CW at 4870 KHZ received most mornings in Las Vegas, NV.

Didn't find much on the net other than references to M89 Chinese Military. When I am able to receive this unknown CW station, Asia SW stations are also very strong.

I am unable to decode the CW - can't figure out how to get HDSDR, FLDIGI, and the Virtual Audio Cable to play nice to decode anything. Something with my configuration is wrong as I can't decode anything despite being able to see it in the tools. If anyone is willing to help, I will sure appreciate it!

Anyone know what/who is broadcasting CW @ 4870 KHZ?

[Token]

I moved this post to Utility because it is not an unknown type of transmission, it is just Morse in ICW.  The Mystery forum is really aimed at unknown types of transmissions, not necessarily unknown sources of transmission.

I initially moved this to Utility thinking it was Russian Navy (the RIS9 callsign got me), but looking at the format I think it is more likely to be Chinese M89.  So moved again, off to Spy Numbers this time, even though M89 is not really Spy Numbers, more military.  It is generally reported / lumped with "numbers" stations.

T!

[ultravista]

Token - how did you determine the RIS9 callsign? I assume you too are able to receive this station?

Do you run the audio through a program or just know Morse well enough?

[Looking-Glass]

Ultravista, refer to my M89 Mid December 2018 logs also on this page, you will see 4.870 as one of the M89 Chinese military CW stations and the "Roundslip" it transmits, it's a regular logging here in Australia.

[ultravista]

Interesting, thanks for the quick reply.

I am amazed with what this active mini-whip is receiving. Mine is the PA0RDT from Roelof Bakker himself. My neighborhood is noisy, lots of RFI everywhere and a suspected marijuana grower using crappy RFI producing ballasts. I theorize it is a grow light as it is on approximately 12 hours a day. When it starts, my SDR display goes wonky until it stabilizes in approximately 5 minutes.

Despite the noise, I am able to receive quite a lot with just the active antenna. In the AM, the NDBs like XSG Shanghai Coastal Radio come in strong.

Thanks again for the feedback, I'll check your logs.

[Token]

Token - how did you determine the RIS9 callsign? I assume you too are able to receive this station?

Do you run the audio through a program or just know Morse well enough?

Yes, I can receive it most mornings.  And no, I did not use a program, I used my ears.  However, if you don't know Morse there are several programs that work pretty well, one of the go-to CW programs is FLDIGI.

T!

[ultravista]

Token, perhaps you can help ... if not, I understand.

I cannot get FLDIGI to decode anything decent. CW is a completed mess and WEFAX images are nearly impossible to read.

FLDIGI is configured for the VAC Line 1 and can 'see' the data streams from HDSDR when Windows 10 pipes the audio through VAC Line 1. This configuration appears to be working; however, the output of the FLDIGI decoder is gibberish.

In Windows 10, Line 1 (VAC) is the primary playback device - not recording device. FLDIGI is configured with Line 1 (VAC) for capture. When I change the SDR output to Line 1 (VAC), the waterfall display in FLDIGI does display the signal; however, it does not decode anything until I enable the Audio Repeater (KS - Kernal Streaming) for Line 1 (VAC).The VAC version is 4.15 (https://vac.muzychenko.net)

For example, CW is unreadable despite being tuned properly in HDSDR and FLDIGI. Squelch on/off doesn't matter - everything is trash.

The FLDIGI decoder becomes legible only if I enable the Audio Repeater (KS) that comes with FLDIGI. When running, the FLDIGI ouput appears to be correct. Validated with WEFAX and CW. In other words, FLDIGI only works properly with the Audio Repeater (KS) running; otherwise the output is trash. I though the Audio Repeater was to pipe the audio elsewhere post FLDIGI, not into FLDIGI.

My FLDIGI settings have been defaulted more than once and the VAC control panel is setup following instructions on the net.

Despite hours of fiddling around with nearly every setting, I still cannot effectively decode anything. I must have done something wrong.

Any ideas?

[ultravista]

It looks like I resolved the problem .. removing VAC 4.51 and installing a different VAC application.
CW & NOAA images are working now.

[Josh]

Some hints on getting software cw decoders to print legibly;
Use the second harmonic of the cw note if you can, that way no band noise to give you false output.
Another is to use a decoder that works well to begin with, such as cwget, wcode, k500, etc.