36/56
M880 ALL EN 2.7.2.docx
9. CHANGING THE OPERATING FREQUENCY
If any specific setting has not been made, the radio selects a frequency channel assigned by AFA
mode (Automatic Frequency Agility). This mode allows the radio channel change as a result of
disturbances detected due to other radio devices operating on the same frequency. There may be
cases in which it is preferable to disable the AFA mode, by operating on a fixed channel selected by
the operator, doing the procedure described below. In AFA mode, the receiver continuously monitors
the frequency band in which it operates and, if the transmission channel becomes too disturbed, the
system decides to “move” to the best available channel.
To verify the presence of disturbances, simply turn-off the transmitter and check the “RF-Link” LED on
the receiver: if it stays on, it means that other devices are using the same frequency. If disturbances
occur during operation, the receiver LEDs “Error_A” and Error_B” will turn off to each reception error
detected.
Reception errors lasting more than 0.5 seconds will put the
receiver on
passive emergency
(see
§
11.2).
9.1. Initial conditions for the frequency change
Make sure the transmitter battery is charged; make sure the
receiver is powered and bring the transmitter as close as possible
to the receiver.
9.2. Frequency change procedure
Turn on the radio remote control, thus establishing the
radio link (the green and blue LEDs on the TX side are
blinking and the RF-link LED on the RX side is ON). Press
the two frequency change controls (CF) at the same time
(see Annex T for identification) and press and release the
START button . The yellow LED on the transmitter will
flash at 1s periods and a BUZZER tone will sound.
Release the two controls (CF): the system turns to AFA
mode automatically.
Select “automatic” Mode:
Press the START button or, to
abort the operation, disconnect the battery pack or, if present,
rotate the key selector.
Select “manual” mode:
To set one of the possible
channels,
use (C.F.x10) command for the tens and (C.F.x1)
command for the units. Exceeding channel 30 (or channel 69 if RF
power is limited to 1mW) makes the system restart in automatic
mode.
Press the START button to memorize the set channel. To abort
the operation, disconnect the battery pack or, if present, rotate the
key selector counter clockwise.
At the end of either procedure wait for about 5 seconds: the
transmitter and the receiver store the data of the new mode. On
the receiver side, you will see the ERROR_A and ERROR_B
(yellow) LEDs flash briefly: this means the frequency change
procedure is being executed.
Press START to begin the sequence of commands. If it does not
occur, it means the procedure was not correctly executed. Turn off
all devices and repeat the entire procedure from the beginning.
NOTE:
With the 433-434 MHz radio module, when power is set to 10% (1mW) the frequency band and the
channels pass automatically from 30 to (band 434.050÷434.775MHz) to 69 channels (band
433.075÷434.775 MHz).
The power level choice (1 or 10 mW) is made by qualified technicians during the radio remote control
installation.
P2
P1
P1
P2