The Australian Silicon Chip magazine has written an article about a kitset for a 100KHz to 2 GHz receiver based on the RTL-SDR that they are selling. Note, you will need to pay in order to be able to read the entire article.
Completing the kit gives you a radio with two antenna inputs, a 5-band preselector, an RF amplifier and an upconverter for the HF bands.
A few weeks ago Akos from the SDR for Mariners blog did a review of the SDR Up 100 Upconverter, and he promised to compare it with the Nooelec Ham-it-up Upconverter when it arrived. He has now done the comparison, and written about it on his blog.
For each test he used a gain of 0dB and the same 20 foot random wire antenna. Interestingly, his results show that the SDR Up 100 significantly outperforms the Ham-it-up upconverter. We believe that this may be as the SDR Up 100 has an LNA built into it whereas the Ham it up does not.
Update: Akos has now included comparisons with various RTL gain settings.
D-STAR or Digital Smart Technologies for Amateur Radio is a digital voice and data protocol used in amateur radio. I was tweeted a link earlier which shows how the RTL-SDR can decode D-STAR text messages and headers (link is in Italian but Google translate can help, and the pictures show more than enough information). By using SDRSharp and stereo mix you can tune to a D-STAR signal, and pass the audio to a command line based decoding program (dstar.exe) which can be downloaded from the above link, which will then decode D-STAR text messages.
Here is also an older video showing D-STAR decoding with HDSDR in action.
Akos from the SDR for mariners blog has written a review on the SDR UP-100 upconverter. The SDR UP-100 is a 50 USD upconverter for the RTL-SDR and similar software defined radios which is made by the same person behind the LNA4ALL low noise amplifier. Upconverters allow the RTL-SDR to receive between 0 and 30 MHz, where ham radio, military, marine and many other interesting signals exist.
In the review Akos tests the SDR UP-100 with a 6 meter random wire antenna and an RTL-SDR. His results show that the upconverter works well as expected. In the future he hopes to compare the SDR UP-100 with the Ham-It-Up Upconverter from Nooelec.
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.
Over on Pawel Janowski’s blog (SQ7MRU) a writeup on how to set up an APRS iGate receiver with an RTL-SDR and cubieboard mini computer has been posted. The article has been written in Polish, but can be translated using Google Translate.
APRS stands for Automatic Packet Reporting System and is usually used by Amateur radio operators to broadcast the current GPS coordinates of something such as a transmitter site/car/boat or high altitude amateur balloon. These APRS packets are received by an iGate and then put onto the internet. Check out aprs.fi for an example.
To create an APRS iGate, Pawel runs a RTL-SDR compatible python program called pymultimonaprs which is used to receive and broadcast the APRS data on to the internet.
YouTube user ranickel and creator of the RANVerter HF upconverter for software defined radios has posted a video showing how to use an RTL-SDR dongle and RANVerter to create a panadapter for an old and cheap Heathkit HR-10 “beginners receiver” ham radio.
He connects the mixer stage of the HR-10 via a capacitor to his RANVerter which then connects to a RTL-SDR dongle.
Update: KN0CKs products are now available at http://www.kn0ck.com/HF_SDR/.
The fourth revision of the miniature HF upconverter for the RTL-SDR by KN0CK is up for sale, now that revision three has just sold out. Revision four has a 120 MHz oscillator, and is capable of receiving the 6m band.
Check out the release post over at KF7LZE’s blog, and the product sales page at the Easy-Kits store.
