20 MHz WWV Broadcast
NIST radio station WWV broadcasts time and frequency information 24 hours per day, 7 days per week to millions of listeners worldwide. WWV is located near Fort Collins, Colorado, about 100 kilometers north of Denver. The broadcast information includes time announcements, standard time intervals, standard frequencies, UT1 time corrections, a BCD time code, and geophysical alerts.
Broadcast Frequencies
WWV operates in the high frequency (HF) portion of the radio spectrum. The station radiates 10 000 W on 5 MHz, 10 MHz, and 15 MHz; and 2500 W on 2.5 MHz and 20 MHz. Each frequency is broadcast from a separate transmitter. Although each frequency carries the same information, multiple frequencies are used because the quality of HF reception depends on many factors such as location, time of year, time of day, the frequency being used, and atmospheric and ionospheric propagation conditions. The variety of frequencies makes it likely that at least one frequency will be usable at all times.
Antennas
The WWV antennas are half-wave vertical antennas that radiate omnidirectional patterns. There are antennas at the station site for each frequency. Each antenna is connected to a single transmitter using a rigid coaxial line, and the site is designed so that no two coaxial lines cross. Each antenna is mounted on a tower that is approximately one half-wavelength tall. The tallest tower, for 2.5 MHz, is about 60 m tall. The shortest tower, for 20 MHz, is about 7.5 m tall. The top half of each antenna is a quarter-wavelength radiating element. The bottom half of each antenna consists of nine quarter-wavelength wires that connect to the center of the tower and slope downwards to the ground at a 45 degree angle. This sloping skirt functions as the lower half of the radiating system and also guys the antenna.
WWV Antenna Coordinates
Frequency (MHz) |
Latitude |
Longitude |
---|---|---|
2.5 |
40° 40' 55.2" N |
105° 02' 31.3" W |
5 |
40° 40' 42.1" N |
105° 02' 24.9" W |
10 |
40° 40' 47.8" N |
105° 02' 25.1" W |
15 |
40° 40' 45.0" N |
105° 02' 24.5" W |
20 |
40° 40' 53.1" N |
105° 02' 28.5" W |
https://www.nist.gov/pml/time-and-frequency-division/time-distribution/radio-station-wwv
Il 21 febbraio 2023 dalle 17.28 alle 17.35 UTC sulla frequenza 20000 kHz in modalità AM, SINPO 3 4 3 4 3.
Ho ricevuto dal sito trasmittente di Fort Collins, CO – U.S.A., “20 MHz WWV Broadcast”, il segnale era sufficiente, anche se c'era molto rumore di fondo.
La stazione radio WWV Fort Collins è a circa 8387 km dal mio QTH
Setup di ascolto: ricevitore SDRplay RSPdx, software SDRuno, antenna End Feed 12,1 m (self-built)
Rapporto d'ascolto inviato all'indirizzo email: wwv@nist.gov, conferma con lettera contenente QSL dopo 21 gg.
Nessun commento:
Posta un commento