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

60 kHz antenna

60 kHz antenna
60 kHz antenna lowered
Credit: NIST

Frost

frost
Frost on receiving antenna and trees
Credit: NIST

More frost

more frost
Frost on trees
Credit: NIST

   

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
Support towers of antenna
Credit: NIST

WWVB antenna
Support towers of antenna
Credit: NIST

satellite dishes
Satellite dishes with antennas in background
Credit: NIST

WWVB antenna
Heavy frost on antenna
Credit: NIST
   

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

Repairs

WWVB repairs
Installing a new insulator
Credit: NIST

Repairs

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

Repairs

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

Antenna Details

Some detailed views of the antenna, and its servicing.

Servicing

WWVB antenna
Rebuilding the antenna
Credit: NIST

Detail

WWVB detail
Detailed view, during servicing
Credit: NIST

Bushing

busing
Busing on top of helix house
Credit: NIST

Detail

WWVB antenna
Rebuilding the antenna
Credit: NIST

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
The transmitter
Credit: NIST

WWVB transmitter
Transmitter during construction
Credit: NIST

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

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
Helix house after old equipment was removed
Credit: NIST

Middle

helix house
Helix house modifications
Credit: NIST

End

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

New Equipment

Construction of the new 60 kHz transmitters.

Transformer

transformer
Placing new 500 kVA power transformer
Credit: NIST

Power amplifier

power amplifier
Transmitter power amplifier unit
Credit: NIST

Control unit

control unit
Transmitter control unit
Credit: NIST

Amplifier

amplifier
Transmitter power amplifier unit with tubes removed
Credit: NIST

Assembly

transmitter assembly
Transmitter assembly
Credit: NIST

Assembly

transmitter assembly
Transmitter assembly
Credit: NIST

Installation

transmitter
Installing a transmitter
Credit: NIST

 

Retired Equipment

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

Transmitter

transmitter
Old 60 kHz transmitter
Credit: NIST

Transmitter

transmitter
Old 60 kHz transmitter
Credit: NIST

Variometer

variometer
Old antenna tuning variometer
Credit: NIST

Created April 22, 2015, Updated July 18, 2018