RTL-SDR - an SDR receiver from a cheap DVB-T tuner on a USB connector

And in order not to combine with some power supplies and stabilizers, you can connect a satellite tuner and an SDR tuner through the simplest signal splitter to the antenna. A splitter should have one input and two outputs. Remembering that the input from the antenna to the satellite tuner should be direct, without any chokes or capacitors, so that the voltage from the sat tuner flows to the converter. The second output may have filters as long as they do not cut the band from 950Mhz to 2100Mhz. The signal from it will be passed through the separator to the SDR tuner anyway.

But then I had a signal at the output of the SAT decoder (when it was turned on). It may have been a bit disturbed. Additionally, the sat decoder controlled the polarization and bandwidth

You will never have the same signal at the decoder output as at the converter output. The decoder transmits the analog signal of the watched channel to the TV set in one frequency, and the converter transmits the received digital signal across the entire band. The satellite tuner works similarly to the SDR tuner.

We didn't understand each other I mean that way out

Loop out - pass-through output + modulator (some).

BOOM i ZONK wrote:

Loop out - pass-through output + modulator (some)

What does it mean to exit with flight? Okay, you mean that sometimes it serves to connect a TV to it, right? This is why this config works:

tomek10861 wrote:

What does it mean to exit with flight? Okay, you mean that sometimes it serves to connect a TV to it, right? This is why this config works:

First, for the sake of clarity, I have to ask if you know what a modulator and LNB are? We need to know this so that someone can answer you briefly and on the subject. Remember that these are two different things. LOP OUT is for connecting another tuner to the antenna. It is the same with the output as above in the photo LNB OUT. I don't get one thing. This extensive topic concerns RTL-SDR, and here I can see satellite tuners.

The modulator converts the carrier into a modulated wave (amplitude / frequency or other effects). LBN is a satellite converter right? So 900MHz from 10GHz, and 2GHz from 11GHz, in short.

As for the decoders, as I mentioned, the sat tuner served me as a power supply for the converter and its config (i.e. when I fired, for example, a German station on the astra, the tuner sent it to the converter to convert it in a given band and set it in a specific polarization). I used the LBN out to connect the SDR - it should see the same as the sat decoder.

Moderated By kriss51:

A colleague writes nonsense. The modulator does not change anything, especially the carrier wave. As already, the carrier wave of a given channel is amplitude modulated by the vision and subcarrier of 6.5MHz audio which is modulated by FM. This is how it is done in such simple modulators. It is so in the will of information and explanation. Please stick to 3.1.14. It is forbidden to publish entries inconsistent with the topic of the forum or discussion thread.
And
3.1.11. It is forbidden to publish entries that do not contain substantive content, contain harmful advice, advice that is not an attempt to solve the problem, and the publication of identical entries consecutive or repeating information from the discussion.

What are you doing this for? you will see some satellite signal and that's it ... You can't decode it because you don't have the keys (encrypted transmission).

I had such a thought through my head, why do you need the whole sat tuner? The converter is powered in the same way as the antenna preamplifier in the antenna ... Digital signals there is only a power supply and probably 12V. I met polarity switching, etc., and yes, but there were 2 separate lines coming out of the head.

The only thing that the sat tuner gives is the initial amplification of the signal, although I can be wrong.

According to Wikipedia

Quote:

Vertical Polarization - 10.7-11.75 GHz range; voltage: 14V 0kHz signal
Vertical polarization - range 11.75-12.75 GHz; voltage: 14V, 22kHz signal
Horizontal polarization - range 10.7-11.75 GHz; voltage: 18V 0kHz signal
Horizontal polarization - range 11.75-12.75 GHz; voltage: 18V, 22kHz signal

The sat tuner makes me a power supply and setting the polarity (in total, it is enough to give 14V and it will come out for one). What am I doing this for? To see what is at 10 GHz, I know that I will not receive satellite TV. :)

Buddy, look at your penultimate post. Stay on topic. The next such posts will be deleted. / kriss51 /

Although 10GHz is a band of hams I just wonder if anyone in Poland deals with it ...
I know from experience that 2m and 70cm in the SP9 district is a paddle ... at least in the vicinity of Katowice ..

Hello, I recently found something like this. Like an sdr tuner, but it is not on the RTL2832 chip, so you would need other drivers for it than usual. It is quite an interesting design, according to the parameters, it should work from 150Khz to 1.9Ghz. Has anyone seen any tests on such a tuner on the net?
http://radioaficion.com/cms/mirics-msi3101-sdr-usb-dongle/

I wasn't looking too much for lack of time, but I think it already works under Linux as SDR.

My previous topic was closed by kriss51, so I'm writing here even though this thread is about the dvb-t tuner receiver.
I am looking for an sdr tuner to receive signals.
I have a dvb-t not only tuner, but its quality is hopeless, the reception of the transmission ends after 500 meters.

I am looking for an sdr receiver with better sensitivity.

You write so loosely and without details that I am not surprised that some of your threads have been closed.

First of all, what "signals" do you want to receive, on what frequency.
Secondly, what antenna do you have and where and at what height. Describe.

What do you pick up, or rather what you stop picking up after these 500 meters?

The NOT ONLY DVB-T tuner or whatever it is with a gray casing is not bad at all, as long as it is not damaged. I had it and the sensitivity is quite acceptable. Of course, it has disadvantages like any other receiver of this type, but it is suitable for listening.

The right antenna is the key to success!
If you have an antenna connected from the kit that is half a cat's tail long, you won't hear much. If someone is here to help, please present the problem specifically!

I admit I wrote a bit illogically.

As for the received signal, not only, the case concerns the reception of the signal from the PMR on the attached antenna, from a distance of about 300 meters I can barely receive the signal, from 500 meters you can not hear anything, while on the second PMR, the signal reception is trouble-free even from 2 km.
It looks like the tuner is broken :(

I am looking for an SDR tuner with better sensitivity than dvb-t.
I mainly care about not receiving the 2m band, then 70 cm and possibly 20m, 40m, 80m

kamilalek1 wrote:

My previous topic was closed by kriss51, so I'm writing here even though this thread is about the dvb-t tuner receiver.
I am looking for an sdr tuner to receive signals ...

Dear colleague. I will not duplicate what has been written to you many times. It is about the basic thing which is a good antenna.
Another thing is your complete lack of SDR knowledge. Instead of reading the topic to which you were sent, you tire other people with strange questions that no one will answer you because no one knows what you mean.
At the beginning, I suggest looking on the Internet what is SDR (Software Defined Radio), what is needed to create such a radio and how to use it.
As you write, you are looking for an SDR tuner and not a DVB-T tuner. So find out that a DVB-T tuner together with the corresponding firmware is an SDR tuner.
Read the rest and then ask.
One more note. If you "blow" the unprotected input of the DVB-T dongle from a short distance, even from the PMR, you can usually throw it (tuner) into the trash. There is a rescue in the form of bypassing the internal receiver but this requires some knowledge and skills.


ps kriss51 did not close the topic for you.

I confirm what the predecessor wrote and I will only add that the antenna attached to the tuner is only suitable for using the radiator as a toothpick and the stand as a fridge magnet.

Make a decent antenna for the PMR band, there are a lot of descriptions on the net.
Connect it with a suitable cable and place the antenna as high as you can so that it is not obstructed by buildings. Suddenly it may turn out that you are receiving PMRs from the other end of the city from other broadcasters.

If it turns out that the DVB-T tuner you have is damaged, you can buy a new one.
You can find it on auction portals by entering the phrase r820t or newer model "r820t2"

I will not agree. The original antenna is extremely useful for conducting analyzes and measurements. Not too sensitive, small shapely and you can't beat the receiver with it.

It is nice to listen to SDR, but compared to, for example, Baofeng or other real radio, it's a lot ... Interestingly, Baofeng is also SDR and has schematics available on the Internet, so if someone wants to improve RTL, I recommend to take the input amplifiers of his receiver.

Today I visited an electronics store, bought an antenna socket, soldered it and plugged into the antenna system of the house. And this is the effect of aerial listening in the vicinity of Tarnów at the frequency of ~ 121 -> 126MHz in AM modulation

nicely
And I started playing with SDR on Android. I even recorded a "guide on how to run it". I only have the impression that the sensitivity is lower than on the PC. Do you know any free SDR program with band preview for android?

In your film you complain about the lack of spectrum while listening to it.
While downloading the software and driver, you will see the "RF Analyzer" application at some point. Install and run. As far as I remember, it has everything you need. Unfortunately, both SDR Touch and RF Analyzer cause frequent crashes of my smartphone, so until I changed to a newer model I gave up playing with these applications and use factory receivers and SDR for PC.

And as for the previous colleague and listening to the air band from a home antenna installation, this is a very thin idea. I think that a piece of wire outside the window cut to size will be a better idea and give a better reception.
You unnecessarily clog the receiver with signals from other ranges, but the signal from AIR BAND itself is relatively low compared to those and it makes black pudding

@methyl Ladies for listening in on frequency data, I will make an antenna for the band, listening to the antenna installation resulted only from running dvb-t on the computer because it was cheaper for me to buy a new TV

Hello, I have SDRSharp, HDSDR and a tuner like in the picture, the problem appears when I try to go above 1553Mhz. Then it gets more noise and the sensitivity drops to zero. I also tried with drivers increasing the reception to 1800MHhz and it does not do anything except that the frequency can be moved higher. Has anyone solved this problem or the only way out is to buy a tuner with the E4000 chip? I use the simplest "turnstyle" antenna to receive.
http://www.arrl.org/files/file/Technology/tis/info/pdf/0210036.pdf

don_viking, and what do you want to listen to on this donglu and this antenna?
The dongle itself could be tested for received bandwidth with a simple broadband noise generator made at the junction of an RF transistor. or zenerka, as long as the zenerka will fly with a noise so high. The antenna itself is dedicated to the GPS operating frequency and I suspect that above and below a few MHz is deaf as a trunk.
For this it is probably a directional antenna.

Personally, I receive various things above 1GHz on the donglu but I have a factory DISCONE antenna on the roof. Efficiency - the gain of such an antenna is nasty but the advantage is the width of the work and the omnidirectional characteristics.

methyl wrote:

Personally, I receive various things above 1GHz on the donglu but I have a factory DISCONE antenna on the roof. Efficiency - the gain of such an antenna is nasty but the advantage is the width of the work and the omnidirectional characteristics.

Just out of curiosity, what is above 1GHz? I only pick up planes and that's it. In addition, my tuner has no restrictions on frequency setting, only when I exceed about 1.5GHz it starts to catch what I have at the bottom (i.e. 400MHz).

Above 1500Mhz you have different types of satellites, such as GPS, INMARSAT and others. Some countries also broadcast DAB + digital radio. The frequency list is online. The band is called L-Band. Recently, on a different directional antenna, I received a signal from INMARSAT satellites that support the satellite phone. The Inmarsat-C decoder shows you which telecommunications company supports a given channel and you also receive short messages. Unfortunately, the Inmarsat-B decoder, which decodes modulation and talks, is only available in premium WAVECOM programs.


The program is attached, USB modulation signal reception. Description on the page below.
http://www.tekmanoid.com/egc.shtml

methyl wrote:

... Plus it is probably a directional antenna .....

No, in the first sentence he writes about his characteristics. You can see that they are two rotated dipoles.

Some satellites work with left-handed polarization, others with right-handed. I have several antennas, one described earlier and it works from 1100 MHz to 1550 MHz above the tuner is already hanging. Another is a helical right and left turn and I am still looking for a satellite radio antenna diagram because I wanted to check if I receive something on it. I just want to find an antenna that would receive the signal omnidirectionally. DICSONE does not receive this type of signals very well, I made one for the 900Mhz to 2000Mhz band. But this is not exactly about the antennas in this topic, but that the tuner freezes above 1550Mhz. I have two of them, and they both behave the same.

I see that nobody answered you specifically, so I checked a few tuners and they have a symptom as you write, some pull without problems to 1600MHz, some can immediately raise the noise level around 1550MHz. It seems to me (I have not checked) that cooling the tuner system will minimize this problem. However, I noticed that a quick jump by 1GHz down and returning to the previous frequency sometimes removes this defect.
However, when it comes to L-band reception, I made a helical (not very carefully) about 85cm long and using a LNA bought in a supermarket for the frequency of LNB SA I received INMARSAT on the frequency 1539, xxx and decoded the frames with the program that you uploaded a few posts earlier. Although nothing appeared in the terminal window, the program generally decoded the data.