A straightforward way to test a 4:1 balun is as follows:

  1. Disconnect the output side of the balun from your antenna or ladder line.
  2. Locate a NON INDUCTIVE (Carbon composition, for example) 200 ohm resistor and connect it directly across the output terminals of the balun.
  3. Using an antenna analyzer, you should find low SWR (1.2:1 or below) across the entire operating range (1.8 to 30 MHz) of the balun.

If the SWR does not read low across the entire operating range, there is a problem with the balun.


If you're testing a 1:1 balun, connect a non-inductive, 50 ohm load across the output terminals of the balun for the test.

Related Products: Antennas