With all the sporatic E around lately, I decided that I needed an antenna for 15 and 10m that I can deploy quickly at home and make some contacts with. I know there are better options, but I do not have space to errect other antennas and I need approval from my land lord to have anything permanent. So for ever i have been using a 40m dipole on 40,15 and 10, to some success mind you, especially on 15m.
So i figure that a trapped vertical for 10 and 15m should be a large improvement over the 40m dipole. My initial tests using a 15m vertical and 2 elevated radials seemed to do quite well, a 9db SNR improvement via Reverse Beacon Network over the dipole, making stations workable that the dipole could not even hear.
So on the CNC machine i routed up some Trap Boards, using a pair of 2000v 100pf caps in series for 50pf capacitance paralleled with whatever inductance was required to make resonance at 15m.
With silicon wire for the radator, and some zip ties for mechanical strength, its not a set and forget depoloyment, this thing will die quickly in weather, but, for something i put up on weekends, it should be fine.
Checking the resonance of the circuit. Looks about right to me.
And this is the completed trap, i should have added some more wire to the toriod rather than bunching the turns up, but i was lazy. Will see how it goes and pull it apart and make changed if needed.