• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar
  • Skip to footer
Part15

Part15

License Free, legal, low-power radio broadcasting

  • Home
  • The ALPB
  • Forums
  • Members
  • About Us
  • Contact Us
  • Log In

RE: Quarter wavelength question

Home › Forums › temp › Quarter wavelength question › RE: Quarter wavelength question

October 8, 2006 at 11:10 am #14065
Rich
Guest

Total posts : 45366

[quote=YvesRoy]If, in a few years, Industry Canada would allow operate an AM transmitter more than 3 meters (let’s say a quarter of wavelength). In this case, with the same power (100 mW), how range will be with a quarter wavelength vertical antenna *WITH* 12 radials of 10 foot copper wire? And *WITH* 120 radials of a quarter wavelength?[/quote]
As always, MW “range” will depend on ground conductivity and path obstructions, quality of the receiving equipment, and interference levels at the receive site. But here are some general numbers based on the FCC’s propagation curves, and estimating that the system with 12 radials each 10 feet long will be about 10% as efficient as with 120 radials each 1/4-wave long…

Freq = 1,600 kHz
Ground conductivity = 8 mS/m
Radiator = 1/4-wave vertical monopole
Distance to 250 uV/m contour:
– using 120 buried radials each 1/4-wave long = 7.7 miles
– using 12 buried radials each 10 feet long = 3.8 miles

//

Primary Sidebar

Who’s Online

There are no users currently online

Footer

Members

Newest | Active | Popular
  • Profile picture of Mark
    Mark
    Active 4 hours, 45 minutes ago
  • Profile picture of Matthew Wells
    Matthew Wells
    Active 11 hours, 21 minutes ago
  • Profile picture of Johny C
    Johny C
    Active 2 days, 2 hours ago
  • Profile picture of timinbovey
    timinbovey
    Active 2 days, 19 hours ago
  • Profile picture of Fred
    Fred
    Active 5 days, 10 hours ago

Copyright © 2022 · Part15 on Genesis Framework · WordPress · Log in