OB8-4M 8 Element 4 Band 40-20-15-10

 

OB8-4M 8 Element 4 Band

 

 

The OB8-4M is an extremely effective, compact and innovative Yagi for the classical four bands 40, 20, 15 and 10m. It is the first trapless Yagi for this frequency spectrum in the world with a single 50 Ohm coaxial feed and with two powerful Moxon Rectangles integrated in its design to improve performance. A mechanically brilliant power house without compromise, the next level of antenna performance!   
 
  • usage of all advantages of the 2 element loaded Moxon Yagi for 40m, see OB2-40M
  • on 20m a 2 element full size Moxon allows for outstanding gain and a super radiation pattern with extremely high F/B
  • 2 fully resonant active elements on 15m are additionally enhanced by the 10m director in front which results in an increase of gain and an optimised radiation
  • a driver-director combination on 10m already delivers higher gain and F/B ratio figures which are increased close to the values of a 3 element monobander due to additional positive effects of the 15m elements in the rear

 

     
OB8-4M   8 Element, 4 Band
     
Bands   40 / 20 / 15 / 10
Gain (dBd) *   3,5 / 4,2 / 4,4 / 4,9
Gain (dBi) **   10,7 / 11,4 / 11,6 / 12,1
F/B (dB)   18 / 25 / 20 / 28
VSWR    
40 m allgemeines setting:    
7,00 - 7,05 - 7,10 - 7,30   1,6 - 1,15 - 1,3 - 1,9
40 m USA phone setting:    
7,15 - 7,20 - 7,30   1,5 - 1,15 - 1,4
14,00 - 14,18 - 14,35   1,5 - 1,1 - 1,4
21,00 - 21,25 - 21,45   1,3 - 1,1 - 1,4
28,00 - 28,50 - 29,00   1,6 - 1,15 - 1,7
     
Elements (number)   8
Active Elements   2 / 2 / 2-3 / 2-3
Max. Elementlength (m)   10.52
Boomlength (m)   6.1
Turning Radius (m)   6.12
Feedlines (number)   1 Coax 50 Ohm
Weight (kg)   45
Windload at 130 km/h   970 N / 1,20 m² / 13,0 feet²