This active antenna is easily assembled from readily available parts provided you have the necessary skills with PC boards, soldering and RF assembly techniques.
Most of the parts, listed above, are available at most electronic supply depots. The one component that may be more difficult to get is the variable open-air ganged capacitor. This unit may have to be scrounged from an old radio.
- Note the ratio of windings: feedback coil, L2, tends to be 1/2 the number of windings of L1, the primary winding
- You can use any guage of insulated magnet wire.
- In the event that you do not acheieve feedback or regeneration, change the polarity of the feedback coil, that is, reverse the direction of winding or the leads that go to the PC board.
- You do not need to wind the coils over each other. They can, however, be wound closer together than illustrated.