$20 USB Dongle SDR Receiver

[LabVIEWguru]

1) I have sent several emails to Realtek about the RTL2832U datasheet and they just refuse to answer. Very curious attitude from a device manufacturer. Perhaps I will call them in the coming week if I don't find a datasheet this weekend.

2) My SDR should be here today!

[ta3as]

1) I have sent several emails to Realtek about the RTL2832U datasheet and they just refuse to answer. Very curious attitude from a device manufacturer. Perhaps I will call them in the coming week if I don't find a datasheet this weekend.

2) My SDR should be here today!

Hi @LabVIEWguru,
I have sent several e-mails to Realtek too. I think there is a "black hole" there :-))
Please let me know if you have any installation problems. There is a networked version of SDR software too. I'm going to test. I'll share the results.

Regards,

TA3AS

[LabVIEWguru]

Hey TA3AS

Well, my SDRs (three of them) didn't arrive, but it gives me time to research and think.
Given the frequency range of the SDR, I wonder about connecting it to a small dish.
Also, it would be interesting to see what comes all the "birds" flying over our heads. Several years ago I tinkered with
DDS and a receiver, using LabVIEW to read the output from a 24 bit ADC to display what existed between freq "A" and "B" - it worked, but not very well.

Now, some very smart people have done all the work. I'll bet some of these smart people are seeing things on their displays they aren't talking about!

[ta3as]

Hey TA3AS

Well, my SDRs (three of them) didn't arrive, but it gives me time to research and think.
Given the frequency range of the SDR, I wonder about connecting it to a small dish.
Also, it would be interesting to see what comes all the "birds" flying over our heads. Several years ago I tinkered with
DDS and a receiver, using LabVIEW to read the output from a 24 bit ADC to display what existed between freq "A" and "B" - it worked, but not very well.

Now, some very smart people have done all the work. I'll bet some of these smart people are seeing things on their displays they aren't talking about!

Hi @LabVIEWguru,
You don't need to setup a dish if you are talking about ADS-B. You can try "log periodic" antennas for your tests if you want to work on 400 - 900 mhz range. I attached pictures of log periodic antennas which are made from PCB. There are a lot of Log Periodic Antennas if you want work over 900 mhz. They are small and easy to install. You can mount a log periodic PCB antenna to a small dish for increasing the receving capability too.

Regards,

[Magnox]

I couldn't resist having a go at this. For those in the UK, cosycave have some suitable receivers at decent prices. I bought the Newsky TV28T from this link:

https://www.cosycave.co.uk/product.php?id_product=220

It comes with a small aerial and connecter adapter for £16.65 delivered and arrived two days after I ordered. Only a touch pricier than ordering from China and a lot quicker. There are other options on their site.

The stick seems to work fine with the SDR#dev software, although I've only just started playing when it arrived this morning. The tiny aerial picks up broadcast FM OK, and just about manages a signal for its intended DBV-T without too much picture break-up. I can almost hit the nearest TV mast with a rock from here but I think they only transmit a watt or so because even on the main TV I need a high gain aerial for a stable reception!

Now I just need to get the ladders on the roof and put a big wire up there...

[ta3as]

I can almost hit the nearest TV mast with a rock from here but I think they only transmit a watt or so because even on the main TV I need a high gain aerial for a stable reception!

Now I just need to get the ladders on the roof and put a big wire up there...

Hi @foxyrick,
Nice to hear that it is working. These dongles sensitivity is not good. Using a LNA makes difference. I see that a lot of owners of these dongles are using cheap CATV amplifiers (broadband signal booster). The feedbacks about these amplifiers are positive. You can try these amplifiers too. Installing these amplifiers close to antenna with short coax cable will be fine. Definitely worth the price, as this is a rugged device meant for outdoor installation.
Please have a look:
http://www.amazon.com/Winegard-HDA-200-Distribution-Amplifier-Adjustable/dp/B00133UTRC/ref=sr_1_1?ie=UTF8&qid=1345576159&sr=8-1&keywords=Winegard+HDA-200

http://www.walmart.com/ip/RCA-10dB-Video-Signal-Amplifier/11600128

Regards,

TA3AS

[Magnox]

Thanks TA3AS, I'm looking at a couple of CATV amplifiers. They are cheap enough that it's hardly worth the effort making my own and then troubleshooting it. My RF skills are limited, (despite having a class A amateur license) as I've never done much in that area.

If I get really into this, I will put a PC in the loft and pop a 5m USB wire out through the wall, high up, so that I can get the receiver dongle as close to the aerial as possible and minimise RF cable length. I used to do that with a wifi antenna connected to a backtrack box, in the days when wireless networks around here still used WEP.

[Magnox]

I've just spend a while trying to get this to work over my network, so that I can monitor the receiver (which is attached to my PC upstairs) from a laptop in the living room.

The way to do this is to use rtl_tcp.exe from the Osmocom RTLSDR tools to connect to the USB stick and put the data onto the LAN, and use SDR# in TCP mode, but it does not work initially, at least on my Windows 7 x64. The stream is killed by rtl_tcp after a second or so. The fix is a different libusb-1.0.dll file...

The rtl_tcp.exe is in the RelWithDebInfo.zip file and can be downloaded here: http://sdr.osmocom.org/trac/wiki/rtl-sdr - direct download link: http://sdr.osmocom.org/trac/attachment/wiki/rtl-sdr/RelWithDebInfo.zip

Extract it and look in the appropriate folder (x64 or x32). You should see the libusb-1.0.dll file with a size of 85kB. It needs to be replaced with an older version from here:

http://sourceforge.net/projects/libusbx/files/releases/1.0.11/Windows/libusbx-1.0.11-win.7z/download

Extract that file and navigate to MS64 (or MS32 as appropriate) /dll folder and copy the libusb-1.0.dll file to the above location, overwriting the original dll.

Then, you can run (from a command prompt)

Code:

rtl_tcp -a 192.168.0.1

replacing the ip address with your PC's address. You should see a response that the E4000 was found and rtl_tcp is listening.

On the client PC, start SDR#, select RTL-SDR/TCP as the front end, and click the front end button to set the IP address of your server PC. Then click play!

[ta3as]

Elonics E4000 tuner datasheet.
See attached txt file. (It is not my share, found from internet)

[bobcat1]

Hi

I have plan to design a low cost discone portable antenna for 50~70 $ and a proper LNA (low noise amplifier) with about 14db of gain and upto 3db noise for about $ 30
 
The LNA will have easy connection to the SDR dongle with proper 75 ohm IEC  or MCX connector.

Any one interested?

Bobi

[borberk]

Do you need help? If not then first jump and then say hop.

[glompos21]

For antena you can see
here

[tanveerriaz]

hare is low frequency up Converter & Pre-Amplifier for sdr.
http://makearadio.com/visitors/nick-sdr.php

[ta3as]

Dear All,
I checked different brands.  Most important thing is that some SDR- sticks have no ESD protection for the E4000 tuner chip, this is already known information, simply solder a BAV99 (SOT23 housing/outline) to the appropriate place on the pcb- board of the stick.
However there are some sticks around wich use a BAV99W . These are very small, so some soldering skills are required here.
I'm attaching a picture that a dongle did not have a ESD protection diode. This diode prevents tuner chip from electrostatic discharge so it is important.

Regards,

[visn]

Hi,

I have lost some money on my Dealextreme order that never arrived. I am in contact with customer services at the moment, and have trust in DX. My other order yielded the ITE9135 chipset which is not compatible. I don't blame the seller as his ebay page made no mention of compatibility, the person who recommended it was at fault.

Now I am looking for someone else to blame, can one of you guys recommend me an ebay seller/dongle that you have used. I already lost money, so I need the cheap option that I can claim against if there is a problem.

[h0nk]

Hi,

I have lost some money on my Dealextreme order that never arrived. I am in contact with customer services at the moment, and have trust in DX. My other order yielded the ITE9135 chipset which is not compatible. I don't blame the seller as his ebay page made no mention of compatibility, the person who recommended it was at fault.

Now I am looking for someone else to blame, can one of you guys recommend me an ebay seller/dongle that you have used. I already lost money, so I need the cheap option that I can claim against if there is a problem.

Look for auctionnumber: 221082072063
Approx 2 weeks delivery time with standard shipping.
Works as expected.


Best Regards

[bobcat1]

My experience with 20$ USD SDR :

I have bought one from ebay few weeks ago - and start playing with it a few day ago.
The received sensitivity is low (-50 ~ -40 dbm) due to noise introduce by PC computer (need to be check with laptop ,maybe batter)
Also a good antenna is essential ,with the current antenna reception is better in the range of +400 MHz.
we will probebly need to isolate the dongle from PC and to add a good wide band LNA in order to have batter reception.
Any how most of the radio transmission today goes digital - it can't be decoded by the SDR (unless you have a dedicated decoder in software)
and I do hope some one will write a decode software for GSM, DECT etc...

All the best

Bobi

  
P.S. > SDR forum's to learn more :

There are 2 active forum regarding SDR :
One with google group's and one with Yahoo

All the best

Bobi  

[Magnox]

I'm really quite interested in this myself now - thanks to the OP, I wasn't really aware of it before other than knowing it existed.

I have what looks like a decent wideband LNA on the way (at a cheap price thanks to the bay of evil).

For the PC noise, a good quality and long (5m, so the dongle can be a distance from the PC and needs less lossy coax to the antenna) USB lead with ferrites will help, or add ferrite rings to a cheap one. I was thinking about isolation too, maybe an ADUM4160 or similar. Possible a screened enclosure would help too. I need more time to play...

I would love to get hold of some of the signals analysis / electronic intelligence software, but they cost an absolute fortune and I've not found one that has a trial version yet.

[borberk]

I tried 5m cable with ferrite toroid at the end but it does not help reducing PC noise much. Maybe the cheapest next step is to use separate DC supply for dongle. Question is how much noise is producing RTL2832 itself with it's own USB signal.

[ta3as]

Hi,
Sticks with this combination (RTL2832 + R820T) are relatively new on the market.
Rafael Micro R820T tuner chip is supportted by Osmocom. You can download new dll files at http://sdr.osmocom.org/trac/attachment/wiki/rtl-sdr/RelWithDebInfo.zip
No details are available on the tuning gaps for the R820T, but the E 4000 is known to have some gaps.
The quoted frequency range for the R820T is 42 – 1002MHz.
The quoted frequency range for the E4000 is 64 to 1700MHz.
By the way if you are planning to order DVB-T sticks, email your prospective supplier first and ask him to guarantee that what he advertises is correct and that the devices contain the E4000 tuner.

Regards,

[Magnox]

So, the R820T gains the amateur 6m band, but loses out on 23cm. However, from reading a little more, people have had success with the PLL achieving lock above 1700MHz with the initial driver. Also the R820T is said to be a little more sensitive.

Could be interesting...

 

[ta3as]

So, the R820T gains the amateur 6m band, but loses out on 23cm. However, from reading a little more, people have had success with the PLL achieving lock above 1700MHz with the initial driver. Also the R820T is said to be a little more sensitive.

Could be interesting...

 

Hi @ foxyrick,
See tuner comparisons:
http://rof.li/pic/tuner_comparison/

73

[mare69]

Hi,

Is there any success story on using "RTL" dongle under freebsd?

I have small http server based on freeBSD and I would like to put online receiver for pings from GRAVES radar. It is transmitter in France transmitting in space (143.050 MHz). "Pings" may indicate presence of meteorites and a chance for VHF Meteor-Scatter communication.

Transmitter: https://maps.google.com/maps?ll=47.348226,5.515308&spn=0.003246,0.008256&t=h&z=18
Background: http://www.britastro.org/radio/projects/MeteorRadarSDRReceiver.pdf

[leosedf]

I've just spend a while trying to get this to work over my network, so that I can monitor the receiver (which is attached to my PC upstairs) from a laptop in the living room.

The way to do this is to use rtl_tcp.exe from the Osmocom RTLSDR tools to connect to the USB stick and put the data onto the LAN, and use SDR# in TCP mode, but it does not work initially, at least on my Windows 7 x64. The stream is killed by rtl_tcp after a second or so. The fix is a different libusb-1.0.dll file...

The rtl_tcp.exe is in the RelWithDebInfo.zip file and can be downloaded here: http://sdr.osmocom.org/trac/wiki/rtl-sdr - direct download link: http://sdr.osmocom.org/trac/attachment/wiki/rtl-sdr/RelWithDebInfo.zip

Extract it and look in the appropriate folder (x64 or x32). You should see the libusb-1.0.dll file with a size of 85kB. It needs to be replaced with an older version from here:

http://sourceforge.net/projects/libusbx/files/releases/1.0.11/Windows/libusbx-1.0.11-win.7z/download

Extract that file and navigate to MS64 (or MS32 as appropriate) /dll folder and copy the libusb-1.0.dll file to the above location, overwriting the original dll.

Then, you can run (from a command prompt)

Code:

rtl_tcp -a 192.168.0.1

replacing the ip address with your PC's address. You should see a response that the E4000 was found and rtl_tcp is listening.

On the client PC, start SDR#, select RTL-SDR/TCP as the front end, and click the front end button to set the IP address of your server PC. Then click play!

I tried it and it works fine with the latest libusb 1.0.14 version.\
The problem is whatever version i use i get intermittend sound. like 0.5sec sound. Too laggy, any ideas?

[Magnox]

Try lowering the sample rate, from the 'Front End' button. It's probably too high a flow of data causing a bottle neck.