9el 144-145MHz Yagi OWL-Ultra Super low noise Yagi

Availability:in stock 989 item(s)
Product Code:144-OWLU-9

Product Dimensions and Weight

Product Length: 5.1000M
Product Widtg: 1.0280M
Product Weight: 3.4000KG
Product Packaging: 2.0000KG
Units in box: 1
Sales price £199.95
Sales price without tax £166.63
Boom Diameter

A 9 element OWL-Ultra (5.1m long) Super low noise, light weight Yagi 144-145MHz Optimised for weak signal (EME) operation - New 2020 Model!

X-pol available upon request & full EME system prices available upon request - This email address is being protected from spambots. You need JavaScript enabled to view it.

OWL Ultra

A 9el 144MHz OWL Ultra installed and ready for action

Fully customisable design - what you want, we will make

If you require a larger diameter boom, rear mount, X-pol, a variation in frequency coverage or other variation, contact This email address is being protected from spambots. You need JavaScript enabled to view it. detailing your requirement for a custom quote.

The G0KSC OWL Ultra is another fantastic design by G0KSC. A low impedance Yagi provides excellent performance. However, traditionally, low impedance has meant narrow bandwidth.

G0KSC developed the OWL (Optimised Wideband Low impedance Yagi) with a folded dipole driven element which this has increased the feed point from 12.5Ω impedance to 50Ω. This along with careful, long duration computer optimisation hasresulted in a much wider bandwidth than previously seen in native low impedance Yagis.

THE Low Noise Yagi dubbed the 'Urban Yagi'

The super low noise characteristics of the OWL Ultra mean you can HEAR as well as be heard in today's modern and very noisy city environments. If you want the very best option for minimal nosie pick-up in Urban and city locations, the OWL Ultra is for you.

Best in Class performance in terms of G/T

All of the InnovAntennas OWL and LFA models for 2020 show better G/T (Gain over Temperature, an antennas ability to recieve weak signals) than any traditional dipole fed Yagi of the same or smaller size. Check the VE7BQH list for confirmation.

9el OWL 3.28x2.7 lossy

AGTC output showing uncorrected G/T at 144.100MHz for the 9el OWL Ultra

Important Note: 

Convergence correction calculator with bent elements and folded dipoles are in use. Additionally, convergence correction should also be applied when hairpin and T-matching systems are in place in the model. If this is note done, artificially high-performance results may occur. Additionally, if matching devices are not applied to the model, associated matching loss will not be considered in the model either and again, artificially high performance figures may result.

9el OWL Correction

Corrected G/T showing a ground-breaking and class leading G/T of -5.83dB for 4 antennas stacked 32.8m x 2.7m (144.300MHz)


Excellent wet weather performance

The OWL Ultra is usable in all weathers. Unlike some antennas that shift frequency and become unusable when wet, the OWL Ultra remains perfectly usable.

Latest and best G0KSC designs only available through InnovAntennas

The OWL-Ultra is the latest, 3rd generation OWL and provides G/T performance not seen at this boom length previously (VE7BQH independant comparison list). The latest G0KSC designs are ONLY available through InnovAntennas.

Elevation lobe suppression is key

One of the reasons the OWL Ultra performance is better than other Yagis of the same size is the special attention paid to elevation lobes during the optimisation process. Whether you believe you live in a quiet location or not, elevation lobes will ensure your received noise floor is higher than it would otherwise be if they were greatly suppressed. Even if you have a shack in the middle of open countryside, if your shack is directly below the antenna or in view of the antenna in certain directions, noise from everything in the shack (from  computers, modems, LED lamps, alarms WiFi adapters etc.) will increas your noise floor. The highly suppressed elevation lobes of the OWL Ultra will ensure your noise floor is as low as possible.

single antennatwo antenna

Elevation lobes for a single 9el OWL Ultra and a pair stacked 2.7m apart. Elevation lobes are a major contributor to unwanted noise pick-up


Mechanical design

The new OWL Ultra is designed in a light weight and very strong package with this particular model using a 1" square boom with through boom (insulated) 1/4" solid rod elements. The driven loop is adjustable in order to ensure absolute minimum return loss figures can be seen and is made from 1/2" tube with 3/8" diameter loop ends which trombone to provide the finalisation tuning ability. The folded dipole is through the boom as are the parasitic elements although the section of loop opposite the feed point is grounded to help reduce noise and to help protect the receiver front-end against static. Grounding the loop in this way also provides a band pass filter characteristic. The feed impedance goes very high quickly once moving away from the 2m ham band and this results in a filter property being added to the antenna for out-of-band signals, received or transmitted.

G0KSC variable element correction applied

SWR characteristics are unparalleled as a result of the applying of G0KSC variable, percentage based correction to all through boom elements. Fixed length element correction does not match software models precisely. The correct method is to apply a % to the elements which vary greatly between the first (reflector) and last (final director) elements. However, an added complication is that the first and last few elements at either end of the boom, require less correction than those centrally mounted on the boom. Don't woory, all these correction issues are taken care of by G0KSC during the design and testing process.

Other benefits include:

  • Marine grade stainless steel fittings
  • Super-light but rigid construction
  • Mill finished boom and elements for highest levels of accuracy
  • Unparralleled after-sales support and assistance when needed


For more information Email Here


Gain: 14.38dBi @ 144.3MHz

F/B: 33.25dB @ 144.3MHz

Peak Gain: 14.23dBi

Gain 10m above ground: 22.83dBi

Peak F/B: 37.43dB

Power Rating: 5kw

SWR: Below 1.2:1 from 143MHz to 145.2MHz

Boom Length: 5.15m

Weight: 3.5kg/7.7lbs

Safe Wind Speed: 160Kph/100Mph

Turning Radius: 2.74m/9ft

Vertical Stacking: 2.7m for minimum under-lobes


Azimuth 9el Ultra

Azimuth plot of a single 9el OWL Ultra


9el ultra 10m up

9el OWL Ultra when placed 10m above average ground