DK7ZB Duoband Yagi 2m/70cm 2+2 Elements

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Duoband DK7ZB Yagi 2m/70cm with 2 Elements on 2m and 2 Elements on 70cm and one Feedpoint * 4,12dBd on 2m * 5,4dBd on 70cm Original design: https://www.qsl.net/dk7zb/Duoband/duoband_2-70_2-3.htm ----- VNA measurements taken in a home room - so they may differ from how the antenna works on the roof or in the field. It will be possible to make a slight correction by shortening the elements with a file. Originally made of boom, about 62 cm long - 20 cm from the Reflector 2 m - this allows the rear attachment to the mast or the installation of a bicycle handle and use as a portable antenna. Attention !!! Adding plastic plugs to the antenna at the end of the aluminum elements "lengthens these elements", which causes a shift in the operating bandwidth. If you are planning something like this, take it into account. ----- Printed parts: 1. box_bottom.stl - 1 pcs 2. box_top.stl - 1 pcs 3. choke.stl - 1 pcs 4. clamp.stl - 3 pcs 5. boom_cap.stl - 2 pcs (optional) ----- The length of the antenna elements (all 6mm aluminum tube): 1. Open-Sleeve-Element 70cm - 318mm 2. Radiator 2m / 70cm - 2 x 464mm 3. Reflector 70cm - 322mm 4. Reflector 2m - 1022mm The spacing of the mounting holes in the boom is shown in the attached photo. From the left, further elements: Open-Sleeve-Element, Radiator, Reflector 70cm, Reflector 2m ----- 50 Ohm Choke: 1. 40cm RG-316 (or similar) - See the attached photos ----- Additional materials: 1. Boom - Aluminum profile 15mm x 15mm x 1,5mm 2. Antenna Elements - Aluminum tube 6mm diameter 3. M3 x 30mm screws (5 pcs) 4. M3 x 10mm screws (10 pcs) 5. M3 nuts (9 pcs) 6. N connector 7. RG316 cable (43 cm) 8. Aluminum sheet or aluminum angle (N socket ground connection with boom - see pictures) Aluminum elements, M3 screws, nuts bought in a DIY store (Castorama) -----