Re: LF: 1476 kHz AM

[Markus Vester <markusvester@aol.com>]

Hi Marcus,

this is really exiting! Up to now, the only proof is the +0.411 Hz offset of Ralph's carrier frequency. Given receiver uncertainties, we can currently only reference it to the swinging-thermostat carrier, which unfortunately seems to have some drift itself. Attached screenshot shows that it faded out here around 4 UT, accompanied by a significant downward frequency shift. From the time of fadeout, we could speculate that the source might be located in north Africa or Europe, and that the thermostat oscillator may have warmed up after local sunrise.  

Tonight I will run a continuous frequency monitor so we know the difference between Ralph's TX and "the swinger" at any time. As an additional reference, I am also observing IRIB Kordestan, which currently seems to be irregularly drifting between +258.1 and +258.4 Hz.

Last not least let's hope that propagation will hold up and give us another opportunity tonight.

Best 73,
Markus (DF6NM)

 

-----Ursprüngliche Mitteilung-----
Von: Marcus PY3CRX PY2PLL <py2pll@py.qsl.br>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Cc: ralph.oppelt <ralph.oppelt@gmail.com>
Verschickt: Sa, 10. Nov. 2018 13:31
Betreff: Re: LF: 1476 kHz AM

Hi Markus / Ralph

Vy interesting.

I compared my measurement to this triangle carrier too / using another ARGO conected to a KiWi SDR in Germany. At the time of my picture the AM signal faded out.

Now my SDR-IQ is powered "forever" as usual so it is very stable even not having any sort of temp compensation. Calibration is ok +/- 0.5Hz. The combo ARGO + HDSDR can be fine tuned to fraction of Hz using 60KHz signals I receive here after sunset.

Lets see tonight.

73
Marcus
PY2PLL + PY3CRX
GG66rf (near S Paulo - BRA)

Em 10/11/2018 01:07, Markus Vester escreveu:

Hi Marcus,

I think you've got it.

I just did another frequency measurement, by injecting a 1475.990 kHz Rubidium-derived local carrier into my AM receiver. Ralph's carrier is at 10.41 Hz (i.e. 1476 kHz +0.41 Hz), with 0.5 Hz sidebands from the AGC acting on the beeps. I'm also seeing that triangle carrier, which is probably from another unidentified broadcast station. During the night it has been swinging between -0.12 Hz and + 0.45 Hz with a 15 minute period, and has now moved up very slightly. Ralph at +0.41 Hz is just inside the top of the swing, just like the weak line in your image.

That's an awesome 9943 km then. Ralph, hold on tight to your coffee cup ;-)

Best 73,
Markus (DF6NM)


-----Ursprüngliche Mitteilung-----
Von: Marcus PY3CRX PY2PLL <py2pll@py.qsl.br>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>; markusvester <markusvester@aol.com>
Verschickt: Sa, 10. Nov. 2018 2:16
Betreff: Re: LF: 1476 kHz AM

Well ... just for fun ...

I set 2 receivers sharing the same mini whip: a SDR-IQ and a KiWi SDR.

On both there is two signals: one at 1476000, another at 1476260 (I read somewhere about Iran 260Hz above).

Using Argo QRSS20 I got two signatures: one that looks like an old ovenized xtal osc and a stable one.

I verified both signals using an KiWi SDR in Germany too. Of course that the 1KHz bips are there. But the same signals are there as well: the ~85mHz wanderin' carrier and the 3W one (this one stable, ~400mHz above 1476000)

May be tomorrow I check this again earlier.

Capture attached. Who knows ...

73
Marcus
PY2PLL + PY3CRX
GG66rf.

Em 09/11/2018 13:05, Markus Vester escreveu:

Thanks Tom and Clemens, that's very nice!

Indeed there are some issues with GoogleMaps, for example last time I looked https://sdr.hu/map didn't show the Kiwi SDR locations. As Clemens indicated, http://k7fry.com/grid/?qth=JN59MN21HF should work. Or in proper coordinates, the wire antenna is attached to the tower at 49.546575 N, 11.019437 E.

Best 73,
Markus


-----Ursprüngliche Mitteilung-----
Von: DK1IS <DK1IS@kabelmail.de>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: Fr, 9. Nov. 2018 14:13
Betreff: Re: LF: 1476 kHz AM

Am 09.11.2018 um 00:39 schrieb Markus Vester:

After the sad demise of all LW and MW broadcasts in Germany, a handful of pioneers came up who are operating legal low-powered medium wave stations in the context of a radio museum or for educational purposes. One of them is Ralph (DL2NDO, one of the participants in the legendary Donebach 137 kHz activation in 2002). He has obtained a transmitting license for 1476 kHz (former frequency of Vienna Bisamberg), built a 3 Watt AM transmitter, and with the help of a small team raised a quarterwave antenna on the Fraunhofer premises south of Erlangen (JN59MN21HF).

Yesterday they got on air for the first time, running a preliminary test transmission consisting of a switched 1000 Hz beeps (one second on, one second off, audio frequency locked to the RF carrier). This pattern will be continued for a few days, before they will eventually.take over the audio from the local DAB student radio "funklust".

The current test pattern is relatively easy to make out in the noise so it may be a good chance for some DX detections.  At night we've actually heard the beeps on Twente SDR and a couple of German Kiwi-SDRs. But I guess using narrowband signal processing techniques, the carrier and coherent tones coud make it much further. The carrier frequency is derived from an OCXO and is currently at 1476000.411 Hz.

Will anyone in the group take the challenge?

Best 73,
Markus (DF6NM)

Fb audible signal at DL0AO (JN59VK)! RX Perseus, Ant Miniwhip, see screenshot. Slight selective QSB. Similar results with their North America beverage.

By the way: all programs using GoogleMaps for QTH-locator identification seem to be inactive because of new Google restrictions.

73,
Tom, DK1IS

df6nm_1476kHz_181110_0600_fadeout.jpg
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