Antenna Trap Kit V2 including cable lugs and cable clips

Description

Antenna trap kit including all supplies for proper strain relief. This kit contains everything you need to fabricate your own trap.

This type of strain relief is recommended for longer or permanently installed antennas. For light antennas and field work, soldering directly to the stage can be used if necessary.

A trap is used as a blocking component for one specific frequency. This can be applied in for example a wire antenna.

Click here!!! Antenna trap kit construction description

A grid-dipper, Nano VNA or spectrum analyzer is needed to tune the stage.

Power: The Trap is designed for QRP use, but appears to work at 100 watts PEP as well, provided it is properly shielded from moisture.

Example 1: multiband dipole antenna for the 10 and 20 meter band using antenna traps

Trap by making two stages that are resonant at the highest frequency. That’s the 10 meter band in this example. If you build the stages in such a way that the resonance frequency is at 28.5 MHz (see building instruction), then signals with this frequency will be blocked. Now start making a standard dipole antenna for the 10 meter band. So a feed point (preferably a 1:1 BalUn) and two pieces of antenna wire of about 2.5 meters ( 300 / 28.5 * 0.95 / 4 = 2.5 mtr). Start with a little more length so you can cut more. Once you have the antenna in resonance for the 10 meter band, the stages can be placed at either end. Now add the other two pieces of antenna wire for the 20 meter section. In our example also about 2.5 meters per side. Now cut the ends to length so that the antenna is in resonance on the 20 meter band. It is also possible to apply this trick a few more times to add a few more bands to the antenna.

Example 2: multiband end-fed antenna for the 40 and 60 meter band using an antenna trap

Start by making one trap resonant at the highest frequency. That’s the 40 meter band in this example. If you build the trap in such a way that the resonance frequency is at 7.1 MHz (see building instruction), then signals with this frequency will be blocked. Now start making a standard end fed antenna for the 40 meter band. So a feedpoint (1:49 impedance transformer) and a piece of antenna wire of about 20 meters ( 300 / 7,1 * 0,95 / 2 = 20 mtr). Start with a little more length so you can cut more. Once you have the antenna in resonance for the 40 meter band, the trap can be placed at the end. Now add the remaining piece of antenna wire for the 60 meter section. In our example about 7 meters. Now cut the ends to length so that the antenna is in resonance on the 60 meter band. It is also possible to apply this trick a few more times. This makes it possible to add more bands.