Tagged: LNB

RTL-SDR Based Itty Bitty Radio Telescope

On his website, David has posted a page showing his results with an “Itty Bitty Radio Telescope” connected to an RTL-SDR dongle. The Itty Bitty Radio Telescope is a small radio telescope that can be used for simple and educational radio astronomy experiments. The telescope consists of an 18 inch directv satellite dish with low noise block (LNB), a satellite finder and an RTL-SDR dongle connected to a laptop.

The LNB converts input frequencies of 12.2 GHz to 12.7 GHz down to 950 MHz to 1.45 GHz which is a range that the RTL-SDR can receive. In his YouTube video posted below David points his Itty Bitty Radio Telescope at the sun and shows the associated increase in the noise floor on SDR# due to solar radio emissions. More information and possible experiments with the Itty Bitty Radio Telescope can be found in this PDF.

Itty Bitty Radio Telescope

Using the RTL-SDR as a Cheap TV Satellite Finder

Finding the correct direction to point a satellite for TV reception can be difficult without the right equipment. YouTube user MegaOscarVideos shows us in the video below how he uses an RTL-SDR to accurately aim his satellite for TV reception.

He uses a TV satellite dish with an LNB connected to a bias-T circuit as the receiver, which is then connected to the RTL-SDR. As the satellite is moved he looks for the direction at which the signal level in SDR# increases the most.

RTL SDR as cheap TV Satfinder

Visualizing Broadcast Satellite Signals with the RTL-SDR

Over on Gough’s Tech blog, Lui Gough has posted about his experiences with visualizing broadcast satellite signals with the RTL-SDR. In his post he shows how to receive broadcast satellite signals by using a LNB, or low noise block downconverter, which allows the RTL-SDR to receive satellite frequencies which are typically out of the range of the RTL-SDR.

Later in the post he also shows what several broadcast satellite signals look like on the waterfall, as well as some of their telemetry signals.

Visualizing Satellite Signals
Visualizing Satellite Signals

Rain Scatter 10 GHz Reception with the RTL-SDR

YouTube user feri67000 who last month showed us that the RTL-SDR can receive 10 GHz signals with a cheap avenger LNB PLL now shows an interesting experiment where he uses a technique known as rain scatter to receive a 10 GHz beacon with his satellite dish pointed in the opposite direction of the beacon transmitter.

Usually communications at 10 GHz are line of sight only, but by using the rain scatter technique, the 10 GHz signal can be bounced off a precipitation cloud and received with line of sight to the cloud, rather than the transmitter.

rain scatter 10ghz LX1DB beacon