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Ferrite antennas

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filter altennas

Clock &
control moduls

AM receiver equipment

AM receiver equipment

There are many different "traditional" time signal transmitters in service worldwide, which emit the specified time signal protocol on different carrier frequencies, and thus provide the basis for a wide range of "atomic clock accurate" synchronized time control systems and radio clocks. These long wave transmitters use an amplitude modulation (AM) to embed the time and date information into the respective carrier frequency.
At the present time we know the following AM-modulated systems:


Location Mainflingen (near Frankfurt / Main), Germany

Carrier frequency: 77,5kHz


Location Anthorn (Cumbria), England

Carrier frequency: 60,0kHz


Location Fort Collins (Colorado), USA

Carrier frequency: 60,0kHz


Location Fukushima Prefecture, Japan

Carrier frequency: 40,0kHz


Location island of Kyushu, Japan

Carrier frequency: 60,0kHz


Location Xi'an, People's Republic of China

Carrier frequency: 68,5kHz

The advantages of long-wave transmitters are both in their wide scope, which is achieved by the interaction of the ground and sky wave and in good building penetration of the signals.
For the reception and evaluation of amplitude-modulated (AM) time signals, 3 modules or functional blocks are required in principle:

a) time signal receiver (IC receiver + peripheral wiring or receiver module)
b) reception antenna (ferrite rod antenna, active antenna)
c) microcontroller for decoding the demodulated signal and for providing the data to a defined interface.

The groups a) and b) are for receiving and demodulating the signal, which subsequently passes a downstream controller for decoding and further processing.

These tasks can be solved in different complex ways, always depending on the requirements that follow from the given electrical and constructive conditions of use of the target product (receiving environment, space, proximity to potential sources of interference, etc.).

HKW offers both individual components and function-tested, modular solutions for the individual implementation of your development tasks and helps you reduce your own development effort.