Meinberg PZF600 - Manual (Page 9)

9
Front panel
Pilot LEDs
The Field-LED is switched on if a DCF-signal with at least minimum field strength
needed for the correlation receiption is detected at the input of the receiver.
Whenever the reception of the pseudorandom PZF signal is not possible but the AM
signal is available, the 'Field'-LED starts to blink once per second with a pulse duration
of 100 or 200ms, corresponding to the demodulated DCF pulses.
The Syn.-LED indicates that the autocorrelation coefficient decreases beyond a value
that is needed and a correct receiption is not possible therefore. This happens if a strong
interferer within the bandwidth of the receiver is present or the transmitter is switched of.
Furthermore, this LED is switched on whenever the receiver is using the AM signal
instead of the PZF signal for synchronisation, no matter if the clock is sync'ed or not.
If the Free-LED is on, it was not possible to synchronize the internal realtime clock to
DCF-time. This condition occures for at most two minutes after switching on the
PZF600, because two DCF-telegrams are checked for plausibility before the data is
taken over. Short disturbance of receiption can cause this state too.
This LED is switched off when the receiver is synchronous, this applies for PZF
reception as well as for AM reception.