QRP EFHW SOTA TUNER

             This is a mini QRP tuner for EFHW antenna tuner. End Fed Half Wave is a type of dipole antenna of which the feeder point is at one end instead of the traditional dipoles where feeder line is connected to the middle point where the impedance is very low. 

ARISS end of year ISS SSTV 2021--Expedition 66 - ARISS Series 19 Lunar Exploration

     Thanks to ARISS team to encouraging SSTV operations from the ISS during the period of Dec 26-31. Used this opportunity to collect fabulous images related to lunar exploration. The transmissions were available worldwide on 145.800 MHz with PD 120 mode.

    Due to limited access to apartment roof have no other option left over than to use 1/4 lambda antenna replacing rubber duck antenna of my classic UV5R handy.

My Setup 😎

    Managed to receive following images of specific passes from North to East and vice versa due to limited open space from apartment balcony.

Slim-Jim Antenna

      Just completed my slim-jim antenna last week. The materials used are 14 SWG copper wire from old electrical cable and some old PVC's and PVC Connectors. I used a 1.9 Meter 1/2" PVC to assemble element and 1'' PVC for covering the element with an PVC end cap on top and an so239 connector at the bottom end to connect the feeder.

      I used a RG 58 feeder cable and a small balun at the antenna feeder end. And here it is at my roof top. The calculation for element length can be found in google. Do consider a parasitic effect due to PVC and build the antenna with a tuning frequency slightly greater than the required tuning frequency.

Balun for 145.000 MHz.

Cheers !!! ...