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WWVB Photo Gallery

The Station

WWVB, the radio station which broadcasts 60 kHz time and frequency signals, is located in Fort Collins, Colorado, about 100 kilometers north of Denver. It is the companion to the shortwave station WWV.

Sunrise view

sunrise view
Credit: NIST
Sunrise view of YAGI antenna with 60 kHz antenna in background

60 kHz antenna

60 kHz antenna
Credit: NIST
60 kHz antenna lowered

Frost

frost
Credit: NIST
Frost on receiving antenna and trees

More frost

more frost
Credit: NIST
Frost on trees

   

The Antenna

The longwave WWVB antenna is so large it is actually a cable strung between several different towers. Here are some general views of the antenna.

Image of WWVB radio antennas
Credit: NIST
Support towers of antenna

WWVB antenna
Credit: NIST
Support towers of antenna

satellite dishes
Credit: NIST
Satellite dishes with antennas in background

WWVB antenna
Credit: NIST
Heavy frost on antenna
   

The antenna for WWVB undergoes regular maintenance, as well as periodic upgrades. These photos were taken during a major upgrade which took place from 1997 to 2000.

Tower

WWVB tower
Credit: NIST
View from top of one of WWVB's towers

Repairs

WWVB repairs
Credit: NIST
Installing a new insulator

Repairs

WWVB repairs
Credit: NIST
Making repairs to the 60 kHz antenna

Repairs

WWVB repairs
Credit: NIST
Making repairs to the 60 kHz antenna

Antenna Details

Some detailed views of the antenna, and its servicing.

Servicing

WWVB antenna
Credit: NIST
Rebuilding the antenna

Detail

WWVB detail
Credit: NIST
Detailed view, during servicing

Bushing

busing
Credit: NIST
Busing on top of helix house

Detail

WWVB antenna
Credit: NIST
Rebuilding the antenna

Transmitter

The 60 kHz transmitter amplifies the time signal before it is sent to the antenna. A 50 Ohm transmission line connects the 60 kHz transmitter in the broadcast house with the antenna. The transmission line begins on huge spools, and is buried in a shallow trench.

WWVB transmitter
Credit: NIST
The transmitter

WWVB transmitter
Credit: NIST
Transmitter during construction

transmission line
Credit: NIST
Covering 50 Ohm transmission line
coax transmission line
Credit: NIST
Preparing to unspool 50 Ohm coax transmission line
power distribution cabinet for transmitter
Credit: NIST
Power distribution cabinet for transmitter
transmission line
Credit: NIST
Transmission line laid in trench; helix house in background
spooled transmission line
Credit: NIST
Spooled transmission line
transmission line
Credit: NIST
Preparing rigid transmission line

Variometer Installation

With the 60 kHz antenna, the transmission line must be matched to the antenna through a coil called a variometer.

Beginning

helix house
Credit: NIST
Helix house after old equipment was removed

Middle

helix house
Credit: NIST
Helix house modifications

End

helix house
Credit: NIST
Near completion of helix house modifications, white down lead yet to be connected to the antenna matching equipment

New Equipment

Construction of the new 60 kHz transmitters.

Transformer

transformer
Credit: NIST
Placing new 500 kVA power transformer

Power amplifier

power amplifier
Credit: NIST
Transmitter power amplifier unit

Control unit

control unit
Credit: NIST
Transmitter control unit

Amplifier

amplifier
Credit: NIST
Transmitter power amplifier unit with tubes removed

Assembly

transmitter assembly
Credit: NIST
Transmitter assembly

Assembly

transmitter assembly
Credit: NIST
Transmitter assembly

Installation

transmitter
Credit: NIST
Installing a transmitter

 

Retired Equipment

The following are the old 60 kHz transmitters and antenna matching transformer

Transmitter

transmitter
Credit: NIST
Old 60 kHz transmitter

Transmitter

transmitter
Credit: NIST
Old 60 kHz transmitter

Variometer

variometer
Credit: NIST
Old antenna tuning variometer

Created April 22, 2015, Updated July 18, 2018