How to Make a CB Dummy Load

By Alan Craig
Make your dummy load with a couple resistors.

It is easy to construct your own dummy load for your Citizens Band (CB) radio set. Since CBs are limited to low power transmitters (less than five watts), the parts are readily available. The dummy load will allow you to test your radio unit without your signal “getting out” beyond a few feet. By using two 100 ohm resistors in parallel your dummy load will exhibit the required 50 ohm load. Since each resistor can handle three watts, the dummy load will handle six watts. Thus, it will safely handle any CB unit that is running the legal limit of power or less.

Place the two resistors side by side and twist the leads together.

Cut the twisted leads on one end to be ½ inch long.

Slide the shortened leads into the center post of the PL-259 connector and solder them in place.

Bend the remaining twisted leads so they make contact with the shield of the PL-259 connector and solder them in place.

Cut off the excess length of the leads that are connected to the shield of the plug.

Use your dummy load by attaching it to your CB rig in place of the antenna.

Things Needed

  • PL-259 connector
  • 2 three watt, 100 ohm resistors
  • Soldering iron
  • Solder
  • Wire cutters

Tip

You can test to verify that your dummy load is made correctly by measuring the resistance between the center conductor and the shield of the PL-259 connector with an ohmmeter. It will show approximately 50 ohms if the dummy load is made correctly.

Warning

Be careful not to burn yourself when you are soldering the wires.

Always be sure that either your dummy load or an antenna is connected to your CB.