VHF Omnidirectional Antenna Folded Dipole 136-174 mHz, 9 dBd 350W

  
DA-1504 is a 4-dipole element array wide band VHF antenna for professional and amateur radio systems. Dipole incorporates 1/4 wave coax line matching circuit optimized for wide bandwidth and accurate matching. Maximum gain is achieved by coupling single dipoles into array. Dipoles in array are coupled by precision phasing cable harness keeping low SWR and minimum insertion losses.

All connections made by soldering and are the one-piece. The vertical distance between centers of dipoles is 0.8 wave length. All antenna parts are made of aluminum. All components of dipole elements are DC grounded for better lighting and anti-static protection.

Frequency range, MHz : 136 - 174. Overall dimensions, cm : H 560, W 90. It is a serially manufactured antenna, so it has high quality and reliability. Important: each antenna produced at personal desired customer frequency, so when you place order, let me know your desired central (transmitting). After placing order, usually we need about 10 days to make an order.

Install the supplied hardware exactly as shown in the photo. Colored markers on each dipole indicate upward direction. Accordingly, the drainage holes at the end of the antennas should point downward.

To calculate the vertical distance in meters, between the centers of the dipoles, it is necessary to multiply the wavelength of the transmission frequency by 0.6-0.8. The wavelength can be calculated by dividing 300 by the frequency in MHz. The mast on which the antenna is installed must be no lower than the upper edge of the upper dipole. The antenna mast must be grounded. If you have any questions about the assembly and installation of the antenna, please contact to me.