Here is a Tri-Band 6/2/440 Collinear antenna that if built properly, using the materials suggested by the author, should give you years of service

This one is more suited for 802.11 operation

Here is a Tri-Band 6/2/440 Collinear antenna that if built properly, using the materials suggested by the author, should give you years of service

Building a colinear antenna for vhf 145mhz, and having about 10dbmore gain than that little 1/4-wave magmount i have not used for 6 years. the actual gain of this antenna is +7.5dbd

These antennas can be stacked to increase gain at low elevation angles and to decrease sensitivity to noise from high elevation angles

The antenna is basically an array of dipoles that are phased aligned by meander line phase-reversal coils that mate each 1/2 wavelength element to one another

A build of a 2-element 1/2 wave collinear j-pole a resonant frequency toward the lower end of the 2-meter amateur band and a vswr of 1.5:1 or better over the entire band

We have multiple 1/4 wave elements fed in series , the radiation from each adds in phase to produce a large vertically polarised omni-directional antenna with bstantial gain

The velocity factor for coaxial cable. For RG58/U coax it is typically .66. All that aside now, lets calculate the 1/2 wavelength of RG58/U coaxial cable with a frequency of 444 Megahertz

A coaxial collinear array for VHF/UHF

Antenna collineare per i 2 metri / 70 centimetri

You can use low-cost coaxial cacle to make a simple high performance omnidirectional vertical antenna

Another components are a connector type F or SMA, insulating tape, PVC pipe with the outer diameter 12 mm and suitable end-seal for this pipe

For the 420–440 MHz band, work UHF repeater systems operating around 435 MHz

Collinear arrays CoA are based on in-phase feeding of radiating elements that lie in the straight line and their radiation is typically broadside perpendicular to the axis of collinear elements

A collinear or co-linear antenna array is an array of dipole antennas mounted in such a manner that every element of each antenna is in an extension, with respect to its long axis

This antenna design is better suited for people who don't have the expensive equipment needed for fine-tuning. Just build it to the exact specs, put it into a PVC pipe some call it a radome and it works

Collinear arrays are high gain omnidirectional antennas. Both dipoles and quarter wavelength monopoles have an omnidirectional radiation

Construction of an easy-to-make collinear 360 degrees omni-directional, vertically polarised, antenna for 802.11b/g wireless networking. The antenna is very robust and compact, and has a gain of approximately 5-6dBi

A very simple antenna to do with the RG-58 coaxial cable. Remove the screen in certain lengths leaving the inner conductor and the dielectric in place

A gain avant 14 DBI rapport avant arriere 20 DBI

This rugged antenna, an omnidirectional collinear, is capable of surviving harsh environments. mounted to the tower, you can obtain approximately 3 - 10 dB of gain over a dipole

The super j-pole is a regular j-pole antenna with a 1/2 wave element mounted above with a 1/2 wave phasing harness connecting the element to the bottom part of the j-pole

I started to build the antenna by cutting four lengths of wire, the measurement is 38.75ins for a half wave @ 145mhz but I cut them at 39.75ins

VHF Collinear antenna project with matching-system for 2 dipoles model Gain = 5.15 DBi

Get a 5/8-inch diameter CPVC water pipe, cut it to 6 inches long for all the coil assemblies