Construction   2-Element (0,15m)    3-Element (0,80m 4-Element (1,00m)
4-Element (1,25m) 4-Element (1,50m)   5-Element (2,00m) 6-Element (2,60m)

2-Element-12.5-Ohm-2m-Yagi for SSB/CW 

F/B > 20dB, stacking distance 1,45m

Your work must be very careful, the design is very critical. The distance between the two elements is only 125mm. The isolated rod in the middle part of the radiator is made by a glassfibre-rod of a tent with 4mm-holes for the elements (4mm-Aluminium).

The complete weight of the antenna is only 155g! As support I use a fishing rod.

 

  Gain 3dB hor 3dB ver
1x2-El 4,5dBd 67,2° 127,4°
2x2-El 8,5dBd 68,2° 40,2°

Element-Positions (drill-holes)

Rad D1
0mm 125mm

Very important: The elements lengths are different for a single Yagi and the stacked version. The interaction between the two antennas results in complete other lengths!

You cannot prove one Yagi of the stacked version alone, they must be assembled as stacked array with 1,45m distance (no less, no more!).

Element-Lengths for using as a single Yagi

  Rad  D1 
4mm 1020mm 977mm 
6mm 1029mm 968,5mm

Element-Lengths for using as a 2x stacked Yagi-group

  Rad  D1 
4mm 1015mm 982mm 
6mm 1023mm 975mm

 

Construction details

The 2x370mm-PTFE-cable RG-188 is wound to a coil as a DK7ZB-match from 12,5 to 50 Ohms. The socket is grounded to the boom.

The distance between the two 4mm-element-halves is 10mm.

 

Single Yagi, hor. pattern, 0dB =4,57dBd

Single Yagi, vert. pattern, 0dB = 4,57dBd

2 x 2-Element-Yagi stacked 1,45m

2 x Yagi, horizontal pattern, 0dB = 8,52dBd

2 x Yagi, vertical pattern, 0dB = 8,52dBd