OPTIBEAM ANTENNAS FROM GERMANY - ENGINEERING AT IT'S BEST

OB8-4M  4 Band 40/20/15/10m

Full-size elements on each band, plus Moxon rectangles on 40 and 20m. Unique low-VSWR direct feed system

Click here for photos of the excellent mechanical construction

• 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/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 pattern

• Adriver-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

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

SWR -  40 m general Setting:  =7,00 - 7,05 - 7,10 - 7,30 1,6 - 1,15 - 1,3 - 1,9

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

Boom length (m) -6,10

Turning Radius (m) - 6,12

Feedlines (number) -1 Coax 50 Ohm

Weight (kg) - 45

Windload at 130km/h - 970 N / 1,20 m² / 13,0 feet²

Price - Euro  2099  (We are showing prices in Euros because of currency instability. For a  GUIDE price in £ sterling, please click here and use the currency converter. If you then wish to retun to this page, please press the BACK button on your browser. For firm £ prices, please contact us)

**=average gain at 20m above ground

*** 28.0-29.0

*=average gain over dipole in free-space - for comparison: 2 el monobander 4 dbd, 3 el 5-6 dbd