User's Manual

Table Of Contents
©1999 Navia Aviation AS 21464-5 Tests and adjustments
USER MANUALNORMARC 7050
MARKER BEACON
7-7
The software adjustments are most easily done with the RMM program, but may be carried
out from the front panel.
This procedure requires that the output power is already adjusted
Set the input attenuation straps on MO1374 according to the marker type. Start out with
22dB attenuation for outer marker, 18dB for middle marker and 12dB for inner marker.
Watch the Monitor parameter RF
LEVEL.
Adjust the potentiometer R850 until RF
LEVEL is 3V at the nominal output power.
(Ref. fig. 7-4)
If this is impossible to achieve, try another strap setting and readjust R850.
Figure 7-4 Input Signal attenuator
7.5 Other adjustments
These adjustments are normally not required, the factory settings should be sufficient.
7.5.1 Output power readout calibration
The C
ARRIER POWER parameter in the RMM Maintenance window is the internal wattmeter. It
is factory calibrated, but may be recalibrated by following this procedure. The software adjust-
ments are most easily done with the RMM program, but may be carried out from the front
panel.
Connect a reference wattmeter to the output signal RF OUT.
Set TX1 to air.
Watch the maintenance parameter C
ARRIER POWER
Adjust the TX settings parameter RF LEVEL until the watt meter shows 2W
Check that the Maintenance parameter C
ARRIER POWER on TX1 is accurate to within 5%.
If not, adjust the Carrier Power potentiometer on TX1 until the parameter shows 2.00W
Repeat for 1W and 0.5W
Repeat for TX2..
0dB
6dB
12dB
16dB
MO 1374
18dB
22dB
R850
28dB
34dB
HBK799/1