Radio
Station WWVH
NIST
radio station WWVH broadcasts time and frequency information 24 hours
per day, 7 days per week to listeners worldwide. The station is
located on the Island of Kauai, Hawaii on a 12 hectare (30 acre) site
near Kekaha at Kokole Point. The information broadcast by WWVH
includes time announcements, standard time intervals, standard
frequencies, UT1 time corrections, a BCD time code and geophysical
alerts.
Broadcast
Frequencies
WWVH
operates in the high frequency (HF) portion of the radio spectrum and
radiates 10 000 W on 10 MHz and 15 MHz, and 5000 W on 2.5 MHz.
Notice:
the 5 MHz broadcast which normally radiates 10 000 W is currently
operating at 5000 W due to equipment failure.
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
From
2000 to 2007, NIST has installed new antennas encased in fiberglass
rather than traditional steel supports, to resist corrosion from the
salty ocean air. The fiberglass design will reduce maintenance and
repair costs. The new design also enables the flexible, lightweight
antennas to be easily lowered to the ground for maintenance, reducing
safety hazards to staff. The improved antennas should reduce signal
downtime for WWVH users. The 5 MHz antenna system consists of
half-wave phased array vertical antennas. The 2.5 MHz, 10 MHz and 15
MHz antennas are base-fed vertical monopoles that radiate
omnidirectional patterns. Each frequency also has a vertical monopole
standby antenna connected to the standby transmitters, in the event
that the primary system fails.
WWVH
Antenna Coordinates
Frequency
(MHz)
|
Latitude
|
Longitude
|
2.5
|
21°
59' 20.9" N
|
159°
45' 52.4" W
|
5
|
21°
59' 10.8" N
|
159°
45' 44.8" W
|
10
|
21°
59' 18.2" N
|
159°
45' 51.3" W
|
15
|
21°
59' 15.3" N
|
159°
45' 50.0" W
|
Modulation
The
signals broadcast by WWVH use double sideband amplitude modulation.
The modulation level is 50 percent for the steady tones, 50 percent
for the BCD time code, 100 percent for the second pulses and the
minute and hour markers, and 75 percent for the voice announcements.
Other
Information about WWV and WWVH
Questions?
Send mail to: wwvh@boulder.nist.gov
Informazioni da: https://www.nist.gov/pml/time-and-frequency-division/time-distribution/radio-station-wwvh
Il
29 marzo 2023
dalle 05.25 alle
05.31 UTC sulla
frequenza 15000
kHz in modalità AM, SINPO 3 4 3 3
3.
Ho
ricevuto dal sito trasmittente sull’isola
di Kauai,
Hawaii – U.S.A.,
“15
MHz
WWVH
Broadcast”, il segnale era sufficiente, con
presenza di
molto rumore di fondo.
La
stazione radio WWVH
è a circa 12394
km dal mio QTH
Setup
di ascolto: ricevitore SDRplay
RSPdx,
software
SDRuno, antenna 14.5 m Terminate Folded Dipole (T2FD) installata
inverted vee (homebuilt)
Rapporto
d'ascolto inviato all'indirizzo email: wwvh@boulder.nist.gov,
conferma con lettera contenente folder informativo e QSL dopo 14 gg.
AUDIO MP3
