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Troubleshooting
7 Troubleshooting
7.1 Duty cycle
The wireless DHC accessories operate in the following frequen-
cy bands:
• 868,000~868,600 MHz
• 869,400~869,650 MHz
In order to safeguard operation of all devices working in this
range, it is legally required to limit the transmission time of de-
vices. Limiting the transmission time minimizes the risk of inter-
ference.
The ‘duty cycle’ is the maximum transmission time. It is the ratio
of the time that a device is actively transmitting in comparison
to the measurement period (1 hour), and is expressed as a per-
centage of 1 hour.
If the total amount of allowed transmission time is reached,
the DHC accessory will stop transmitting until the time limit is
reached.
For example, when a device has a duty cycle limit of 1%, it is
only allowed to transmit 36 seconds in 1 hour. After this, it will
stop transmitting until the 1 hour limit is reached.
DHC accessories fully comply to this limitation and use 2 fre-
quency bands with a duty cycle of respectively 1 % and 10%.
During normal operation of the DHC accessories, this limit is not
usually reached. However it is possible that the limit is reached
