RTL-SDR with Forced Air Cooling

Over on his blog, Nobu has uploaded a post showing his experiments with a forced air cooled RTL-SDR dongle (note the blog is in Japanese so use Google Translate). A tiny fan from RS components is attached to the case of the dongle and draws power from the dongles own power regulator. Nobu also replaced the crystal oscillator with a flat packaged oscillator for a better fit.

The translation is a little difficult, but it appears the fan was able to successfully stabilize the temperature. This may be an alternative to the temperature controlled oscillator (TCXO) RTL-SDR modification.

EDIT: It seems that the fan is not to improve temperature stability, but rather to improve sensitivity. Nobu has referenced this experiment which shows that improved heat dissipation improves the dongles sensitivity.

Fan Forced Cooled RTL-SDR
Forced Air Cooled RTL-SDR
Tweet
Share
Reddit
Vote
Email

GNSS-SDRLIB: Real Time GPS Positioning with RTL-SDR

Over on YouTube user taroz1461 has posted a video showing an RTL-SDR getting a real time GPS location fix using his GNSS-SDRLIB software package. Taroz1461 used an RTL-SDR modified with a temperature controlled oscillator (TCXO) to improve the frequency stability of the dongle.

In the video description he writes that GNSS-SDRLIB will soon have RTL-SDR support in the next update.

GNSS-SDRLIB: Real-time positioning with RTL-SDR (DVB-T Dongle)

Tweet
Share
Reddit
Vote
Email

SDR# Website and Downloads Removed

Update: The author has updated the website with an explanation of why he took it down. He has also restored download functionality so now sdr-install.bat will work again.

The SDR# website, download links and repositories have been taken down and probably won’t be back for a number of days or weeks. This means the sdr-install.bat file will not work as well. If you already have SDR# installed it will continue to work as normal.

We aren’t exactly sure why this has happened, but it seems the author of SDR# did not like the many forks of the software that have been recently popping up. The forks may have been violating the licence that SDR# is under.

If you are new to RTL-SDR, our Quickstart guide has guides to using HDSDR and SDR-CONSOLE to try while SDR# is unavailable. HDSDR and SDR-CONSOLE are two good alternatives to SDR# but are slightly more difficult to set up and use.

See the Reddit discussion on this here.

Tweet
Share
Reddit
Vote
Email

Direct Sampling Front End Board

Over on this Japanese language blog, ttrftech has been experimenting on a type of direct sampling front end board (Use Google Translate) for a direct sampled RTL-SDR dongle. More info about his direct sampling front end can be found on this post. Translated, it appears his board has the following feautres.

  • Filter x2 up to fifth order
  • RF switch
  • Amplifier
  • Power regulator
  • Input transformer (optional)
  • The RJ-45 (optional) or the SMA input connector
  • Power supply to the antenna
  • Output to U-FL or SMA (ipex) connector

The results seem to show his board does improve reception. Note that the RJ-45 appears to be the antenna. There also appears to be review of the board by “pup” here and a video showing the board filtering out a broadcast FM image in the video below. On Pups blog there are also more posts about the board under this tag.

ダイレクトサンプリング向けフロントエンド基板の実験①

Direct Sampling Front End
Direct Sampling Front End
Tweet
Share
Reddit
Vote
Email

New DAB Player for RTL2832U

A new Digital Audio Broadcast (DAB) player has been released for RTL2832U dongles (Link text is in German use Google Translate to translate). This player uses the official drivers and not the RTL-SDR drivers, although we believe the DAB demodulation is still done in software. You will need to install the drivers provided on the download page to run this DAB player. For R820T models, the Treiber2.zip file should be used and for E4000 Treiber.zip should be used. You will also need have installed the Visual C++ Redistributable package to run the program.

The software UI is written in German, but its controls are easy to figure out for non speakers.

An alternative DAB player that uses the RTL-SDR drivers is SDR-J.

RTL2832U DAB Player
RTL2832U DAB Player
Tweet
Share
Reddit
Vote
Email

Receiving Mexican Pirate SSTV on Military Satellite Frequencies with the RTL-SDR

Happysat, a reader of RTL-SDR.com wrote in to let us know his experience with receiving Milsat pirate SSTV images using his R820T RTL-SDR and his homebrew QFH antenna. During his research he found that Brazillian Mexican Pirates hijack military satellite transponders to send SSTV pictures of their families on 255.560 MHz 22.4° West UFO F7 (USA 127).

Happysat writes that he found an active signal on that frequency most of the time. To receive the SSTV signal happysat used the free RX-SSTV software.

SSTV is an acronym for slow scan television and is a mode usually used on HF (0-30 MHz) frequencies by ham radio enthusiasts for sending out digital calling cards.

More information about pirate SSTV can be found here.

Edit: From our Facebook page comments, it seems these signals are actually from Mexican pirates. More info here http://www.qsl.net/py4zbz/ec/ec.htm.

Milsat Pirate SSTV
Milsat Pirate SSTV in SDR#
SSTV Image
Received SSTV Image 1
SSTV Image
Received SSTV Image 2
Tweet10
Share
Reddit
Vote
Email
10 Shares

Modesdeco: Now Supports Simultaneous Reception of Mode S and Mode A/C

Modesdeco is a Windows/Linux/OSX/RPi compatible command line ADS-B Mode S decoder built for the RTL-SDR. It natively supports the BaseStation format and so can be used with the BaseStation software without the need for com port converters.

Modesdeco has recently been updated to allow for the simultaneous reception of Mode S and Mode A/C. Mode S provides location data for ADS-B while Mode A provides an identification code and Mode C provides the aircraft’s pressure altitude.

Tweet
Share
Reddit
Vote
Email

Effect of a Filter on RTL-SDR ADS-B Reception

Over on YouTube user Adam Alicajic has posted a video showing the effect of a filter tuned for 1090 MHz used on ADS-B reception. Adam switches the filter in an out showing the difference in the number of received ADS-B frames. With the filter enabled he is able to receive around 1200 messages per second and without only around 800 messages per second.

A filter (aka preselector) can help to reduce out of band interference from strong signals.

DVB-T dongle receiving the ADS-B using the filter

Tweet
Share
Reddit
Vote
Email