| 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! |
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| 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) | 50 | |
| Windload at 130 km/h | 970 N / 1,20 m² / 13,0 feet² | |
| Price *** | 2.219,00 EUR |
| * = average gain over dipol in free-space / for comparison: 2 el monobander 4 dBd, 3 el 5-6 dBd |
| ** = average gain at 20m above ground (= dBd + 2.15 dB isotropic + about 5 dB ground reflection) |
| *** = outside EU minus 19% tax – subject to change |
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