Category Archives: Digital

DuinoVOX USB Digital Modes Interface

From Kevin, KB9RLW

My home brew USB interface for all ham radio digital modes. Unique in that it uses an Arduino micro controller for the VOX function. This makes it very flexible and tweakable. One thing I didn’t mention in the video. You want to set the playback volume of the interfaces sound card to maximum on your computer. Then use the drive level knob to adjust the audio drive to your rig. This gives the vox plenty of signal to work with.

I intended to include the Arduino source code here, however youtube wouldn’t allow some of the characters in the code!!! Very disappointed, but I understand why.

I put that info on my blogspot blog. You can get the schematic and source code here.


SDRPlay Running 3 Virtual Receivers with SDRuno v1.2

Propagation was quite poor when this video was recorded, but for better or worse, the SDRplay is connected to an 85 foot vertically oriented triangular loop and is simultaneously receiving the AM BCB, 75 meters, and 40 meters. Toward the end of the video, the 3 virtual receivers are tuned to 3885, 1885, and 7290, the 3 AM calling frequencies on 75m, 160m, and 40m. Since Radio China International was sitting on 7285 the 40 meter receiver was tuned there at the end. The SDRplay was set to receive a 10 MHz swath of the spectrum for this video. The SDRplay does a beautiful job receiving the AM aircraft band, the VHF-UHF public service frequencies, the FM broadcast band (in stereo) and pretty much anything you can think of between 10 kHz and 2 GHz.

SDRplay running with Android mobile phone

From Mile, Z33T.

Turn your mobile phone into an All mode communications receiver from 0.1 to 2000 MHz !
This video shows “SDRplay” Software Defined Radio running with my Android mobile phone, receiving USB on 20m Band (14 MHz).
The software “SDR Touch” and SDRplay driver are downloaded from Google Play Store.

Some mobile phone USB ports simply do not have enough power for the SDRplay receiver (my phone usb port, did not provide enough power also), therefore, I sliced the USB OTG cable and added (soldered) additional connector for an external 5 volts power source, or 5V battery pack. In that way, the external battery is charging the mobile phone and powering the SDRplay-receiver at the same time.

CubeSat Telemetry Demo

From Scott Chapman

You can do a LOT of different things with Software Defined Radio (SDR). One aspect that I particularly enjoy is satellite telemetry.

Here is a basic overview showing some of the software options for receiving & decoding telemetry from the many amateur, educational, & government satellites that orbit our planet.

Many computer, SDR, & software combinations work well. In this demo, I was using Windows-7, SDRPlay, HDSDR, Orbitron, UZ7HO high-speed soundmodem, DK3WN AGW OnlineKiss, MXL GroundStation client from Univ. of Michigan, & the Online Telemetry Forwarder from DK3WN & PE0SAT.

We owe great thanks to all the amateurs who have documented each satellite, put their own reception reports online, and written software to make this all possible. The call signs listed above belong to people who have done a great service that contributes not only to our hobby entertainment, but in many cases the telemetry that we all download will be of great benefit to the schools and other organizations who are using data from the growing number of satellites in orbit.

Winlink Digital Mode

From Cliff N4CCB

Winlink lets you easily send/receive email from anywhere on the face of the Earth with your HF radio! In the first 7 minutes, I give you the background information on Winlink… what it is, why it’s important, and how it works. Then, I fire up the computer and a QRP radio (naturally!) to do a demo of sending and receiving email.

Antenna Testing Using WSPR

From Randy K7AGE

I’ll show you how to use WSPR software to check to see if my antenna is working. WSPR sends your call sign, power level and grid square during a nearly two minute transmission. Receiving stations decode your transmission and post the results to an online database. You can use a website to view a map of of the station that you have heard and stations that have heard you.

WSPR is written by Joe Taylor, K1JT

WSPR, software and users manual…

WSPR Net, map display

Grid Square Map

Setallar WSPR, receiver kit