Setting up SDRAngel for receiving DCF77.

MSF, DCF77, TDF, WWVB
srcejon
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Re: Setting up SDRAngel for receiving DCF77.

Post by srcejon »

jaro61 wrote: Thu Feb 09, 2023 3:35 pm One more thing. I pressed the X button on the module and now I can't turn it off. How do I turn it off?
It's fine being checked - in fact, it's probably a bug that it doesn't start out checked (as it means the X trace is displayed - which is what you want)
f4exb
Posts: 12
Joined: Tue Jan 24, 2023 7:16 am

Re: Setting up SDRAngel for receiving DCF77.

Post by f4exb »

Hello,

you should look into these MLA-30+ loop antennas with amplifier (the magic is in the amplifier actually) from China. By just doubling the loop in two turns (you need to use another wire and form it) you can get amazing results at low frequencies.

Brgds,
Edouard, F4EXB.
jaro61
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Joined: Thu Jan 26, 2023 8:51 pm
Location: Stropkov, KN09TE

Re: Setting up SDRAngel for receiving DCF77.

Post by jaro61 »

f4exb wrote: Sun Feb 19, 2023 10:43 am Hello,

you should look into these MLA-30+ loop antennas with amplifier (the magic is in the amplifier actually) from China. By just doubling the loop in two turns (you need to use another wire and form it) you can get amazing results at low frequencies.

Brgds,
Edouard, F4EXB.
Do you mean such an antenna? MLA-30+
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RTL-SDR
f4exb
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Joined: Tue Jan 24, 2023 7:16 am

Re: Setting up SDRAngel for receiving DCF77.

Post by f4exb »

Indeed... the original loop may work but doubling the turns makes it a great Rx antenna from ~DC to 10m.

Brgds,
Edouad, F4EXB.
jaro61
Posts: 55
Joined: Thu Jan 26, 2023 8:51 pm
Location: Stropkov, KN09TE

Re: Setting up SDRAngel for receiving DCF77.

Post by jaro61 »

If I wanted to cover the 2m band as well, would you also recommend this antenna K-180WLA? Or should I use 2 antennas? For 10m band and 2m band.
Click here Antennas
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f4exb
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Joined: Tue Jan 24, 2023 7:16 am

Re: Setting up SDRAngel for receiving DCF77.

Post by f4exb »

Hello,

LF, HF and VHF antennas are different beasts. For LF the loop with amplifier will work fine and so will it up to the HF range not sure for VHF probably not or other types of antennas will do better. You have to consider the amplifier bandwidth too. I have found the MLA 30+ goes below its advertised limit of 500 kHz but didn´t try it much above 30 MHz. For HF you could use a loop antenna like this or a dipole with appropriate length although if it is just for reception the size may not be that critical knowing that as your antenna gets smaller vs the wavelength the less efficient it will be. For VHF a dipole will work but as the size of elements get smaller you may afford a 3 or 5 element yagi in a relatively small volume and it will give you appreciable gain at the expense of higher directivity which may also be desirable to eliminate unwanted signals. You also have to place your antenna as high as possible to have enough distance from the ground. As the wavelength diminishes the less height you may need so at VHF a person's height could be enough to get decent results. If you live in a city in a concrete building the building itself because of armored concrete can be considered as "ground" so any antenna will not work very well inside the walls.

Brgds,
Edouard, F4EXB.
rbannocks
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Joined: Tue Jun 27, 2023 9:28 pm

Re: Setting up SDRAngel for receiving DCF77.

Post by rbannocks »

I will be interested to see the results. CAn you advise how to adjust the displayed spectrun. Mine shown negative frequencies.
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srcejon
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Re: Setting up SDRAngel for receiving DCF77.

Post by srcejon »

Decrease your sample rate or increase decimation (DEC). Both of which will reduce the bandwidth / span (and thus reduce the range of frequencies displayed in the spectrum).
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