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Körner 15.11 specs

At last – a new high performance FM antenna for serious DX or professional use: The FM15.11

Körner 15.11
Körner 15.11

Superior performance for size – and highest quality construction!
High gain – higher average gain than bigger designs due to special wideband tuning of the directors in combination with a horizontal folded dipole.
Wide bandwidth – covers the FM band with consistent high performance.
Superior F/B – even compared with much bigger designs, now improved compared to previous FM15 versions. Rear response is minimised over the entire rear half-plane, not just directly to the rear, and over the whole bandwidth.
Lowest SWR – see measurements below, lowest mismatch loss across the band.
Lowest loss signal transfer – very low loss wideband halfwave coaxial balun for 75 Ω.
Optimized 5 element reflector wall – really makes a difference for F/B.
Predictable performance – all elements are electrically isolated from the boom to minimize boom effectsand common-mode currents on the connected coax.
No phasing lines – no coupling to the boom that degrades the optimised pattern.
Superior mechanical stability – heavy duty boom and mast clamp.
Maximum mechanical durability – continuous and seamless elements, heavy duty mast clamp and stainless mounting hardware.
Reasonable size – size is not much bigger than typical 8 element designs.
Detailed specification overleaf – all parameters modeled or measured!

On the web: http://ham-radio.com/k6sti/korn1511.htm

Modeled results: Modeling software: MMANA-GAL v. 1.0.2.20

Gain (dBi) and F/B over rear half plane
Gain (dBi) and F/B over rear half plane
Gain (dBi) and F/B directly to the rear
Gain (dBi) and F/B directly to the rear
Horizontal and vertical patterns
Horizontal and vertical patterns
Measured SWR SWR 88 - 108 MHz (Including balun, measured with 12th wave transformer)
Measured SWR SWR 88 – 108 MHz (Including balun, measured with 12th wave transformer)

Gain comparison*:

Forward Gain

F/B comparison*:

Front-to-Worst-Backlobe ratio

 *) Modeled by Brian Beezley, http://ham-radio.com/k6sti/, using AO-Pro 8.08 Antenna Optimizer

Electrically isolated element mounting hardware
Electrically isolated element mounting hardware

Maximum gain: 11.8 dBi
Impedance: 75 Ω unbalanced (50 Ω with additional wideband 12th wave transformer)
Dimensions:
Length: 3.74 m / 147”
Width: 2.08 m / 82”
Height: 1.48 m / 58”
Turning radius: 2.35 m / 92.5”
Design:
Peter Körner, M.Sc.EE
Lund
Sweden
Email: p_korner@hotmail.com

Manufacture and sale:
VHF TEKNIK AB
Godsvägen 2
S-231 62 Trelleborg
Sweden
Tel. +46 410 464 30
Fax +46 410 462 11
Email: info@vhfteknik.se, sven@vhfteknik.se
Web: http://www.vhfteknik.se/

© 2011 original specs sheet