SP 130: AM and FM with SDR (20 pts)

What You Need


To receive AM and FM transmissions with a simple dipole antennas and a Software-Defined Radio (SDR) device.

Necessary Equipment

You need this RTL-SDR kit (under $40):

RTL-SDR Blog V3 R820T2 RTL2832U 1PPM TCXO HF Bias Tee SMA Software Defined Radio with Dipole Antenna Kit

Getting SDR Sharp

You need this software to run the SDR dongle.

Don't plug in the RTL-SDR dongle yet. If you already plugged it in, unplug it.

In a Web browser, go to


Download the "Windows SDR Software Package", as shown below.

On your Windows system, right-click the sdrsharp-x86.zip file and click Extract, "Extract All".

Double-click install-rtlsdr.bat, as shown below.

Installing the Zadig Driver

Plug in your RTL-SDR dongle. If it attempts to automatically install drivers, wait for that process to finish. If it fails, that's OK.

On your Windows system, open the folder you extracted SDR Sharp into. That folder should contain the zadig.exe file.

If the file is not there, you can download it here.

Right-click the zadig.exe file and click "Run as Administrator", as shown below.

Approve any security questions that appear.

In Zadig, click Options, "List all Devices".

Make these selections, as shown below.

When the settings match the image below, click "Replace Driver".

Approve any security questions that appear.

Connect the Antenna

The kit comes with a couple of skinny coaxial cables and antennas. Connect the larger "bunny-ear" dipole antenna to your RTL-SDR, as shown below.

Using SDR Sharp

On your Windows system, double-click SDRSharp.exe, as shown below.

In SDR Sharp, at the top left, click the gear icon.

In the "RTL-SDR Controller" box, make these selections, as shown below.

In the "Radio" pane, select AM, as shown below.

Adjust the frequency to an AM station that works in your region, as shown below. To adjust it, click in the top half of a digit to increase it, and the lower half to decrease it.

Tune it in until you hear clear radio.

SP 130.1: AM Reception (10 pts)

The flag is covered by a green rectangle in the image shown below.

SP 130.2: FM Reception (10 pts)

Close SDR Sharp and restart it.

Configure the controller for a higher sampling rate and a different mode, as shown below.

Use the WFM band with a bandwidth of 200,000. Tune in an FM station so it's clear.

The flag is covered by a green rectangle in the image shown below.


RTL-SDR.COM Quick Start Guide

SDR# FM Radio

Posted 12-12-20
Zadig download link added 1-6-21