ANTENTOP- 01- 2012, # 016

EH Antenna for the 20- meter Band

Next step is to connect the antenna parts between each other. The stage requires patient and attention.

At first, connect by wire in plastic insulation the upper end of the lower cylinder with lower end of the tuning inductor. (See Figure 1) For this connection do holes in dia 2- mm near the upper end of the lower cylinder and lower end of the tuning inductor. Take the length of wire that a little more the distance between the holes. The wire should go inside the tube and the wire should touch by all it length the inner surface of the tube. Tin ends of the wire. Bend the tinned ends of the wire onto 90- degree. Then insert the tinned ends of the wire into holes. Use all tools that you can find or make. I personally used a wood stick with a slot. An end of the wire was inserted to the slot then the end was inserted into the hole. After that the end was bended and soldered to the cylinder. Then next end of the wire was inserted into the hole and straight away bended and soldered to the tuning inductor.

At second, connect by wire in plastic insulation the lower end of the phase inductor with upper end of the tuning inductor. (See Figure 1) Preliminary do the same things as was done with the first wire. However the wire should go into center of the tube. You may use some kind of spreader to keep the distance equal inside the tube. Figure 8 shows the wires inside of the tube.

At third, last step to make the EH- Antenna. Install the cap with an RF- socket and an input inductor. Figure 9 shows the cap. Do holes for fastened RF- Socket by screw with nuts and install this one. Figure 10 shows the cap with the RF- Socket. Cut half part of plastic from the cap, install wires and input inductor. Figure 11 shows the cap with the RF- Socket and the input inductor. Well, do not hurry to install the input inductor it should be installed after a preliminarily tuning of the antenna. The inductor helps get the minimum SWR in the antenna. Tuning inductor may contain 5- 7 turns. Diameter of the inductor is 12- 15- mm. It made by wire in plastic insulation (similar wire that was used for the phase inductor). The inductor must be placed perpendicularly to axis of the plastic tube.

Figure 8 Wires inside of the Tube

Figure 9 Tube Cap

Figure 10 Tube Cap with RF- Socket

Figure 11 Tube Cap with RF- Socket and Input Inductor

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