2 el. 40m Yagi

40 meter 2 element beam Yagi (7 MHz).
Shortened element with high-Q loading coils PTFE insulated and weatherproof.
Boom made from 55 and 50mm tube.
Elements made from 35 to 12mm tube.
Insulating Guying provided for boom and elements (longevity more than 25 years): see pictures.

Specifications

• Forward gain in free space (dBi): 5.0

• F/B ratio (dB): 15

• Frequency coverage (MHz): 7,000 - 7,200 MHz (see below for possible settings)

• Bandwidth @ 1.5 VSWR (kHz): 100

• Feed impedance (ohms): 50

• Power handling (kW): 5

• Longest element (m)/(ft): 13.76/45.1

• Boom length (m)/(ft): 5.50/18

• Turning radius (m)/(ft): 7.49/24.6

• Weight (kg)/(lb): 25/55

• Wind survival (km/h)/(mph): 125/77.7

• Standard Mast size (mm)/(inch): 50/2 (55/2.25 or 60/2.50 optional at no extra cost)

• Kit DXM40-3sb for DXM40-2 available, for transforming this antenna to a 3 element 40m  short-boom Yagi (DXM40-3sb) → New in 2017

Possible settings → New in 2013

#1  CW preference: 1.3:1 VSWR on 7.000 - 1.05:1 on 7.030 - 1.8:1 on 7.120 - 2:1 on 7.150 MHz

#2  SSB preference: 1.7:1 VSWR on 7.050 - 1.05:1 on 7.100 - 1.9:1 on 7.200 MHz

(See analyzer Plots from the pictures above)

Greases supplied

2 kinds of grease are supplied with your antenna:

• Aluminum contact grease: Professional grease containing 30% aluminum particles, recommended for the assembly of aluminum antenna tubes. Prevents binding, corrosion and the formation of aluminum oxide, and allows easy dismantling of antennas after several years.

• Copper conductive grease: Professional conductive grease with a copper base, recommended for all hardware requiring a sound and lasting electrical contact. Prevents oxydisation, damp ingress, and limits chemical reaction between stainless steel and aluminum.

Balun or no Balun ?

• This antenna does not require any balun.

• To avoid having stray current on the braid of a coaxial cable (often the cause of RF and/or TVI/BCI), you can make your own 1:1 choke balun with coaxial cable. Explanations are provided with antenna assembly instructions. (See also our F.A.Q).