Pag. 12
MRK950
dual true diversity receiver
proposes the new squelch level. The user could then
accept, refuse or modify it by means of the buttons
and of the knob.
Note: during the Autoset SQUELCH function
it is not possible to change the unit of the
squelch voltage.
SCAN
The SCAN function is very useful to discover the best
channels to use (the channels with lower RF noise)
in the selected group. After pressing the SCAN but
-
ton, both receivers are ready to start with the SCAN
function. It is possible to select the receiver 1 or the
receiver 2 or both (i.e. simultaneously scan on dif-
ferent groups).
With the first menu on the display it is possible
to choose the group of channels for the scan and,
pressing the knob, is possible to define a reference
line drawing in the final scan result graphic, just for
user reference. Pressing the knob the focus change
between REF LINE and GROUP.
Pressing the START button, an alert window remind
the user to switch off all the transmitters before
starting the SCAN, press START again and the SCAN
function will start. At the end of the analisys, on the
display it is possible to see the graph of the RF levels
measured in each channel and, rotating the knob, it
is possible to move the marker on the bottom of the
graph just to see the channel number and the RF
level measured for that channel.
Pressing the knob it is possible to have a graph in
rank order instead of channels order, so, it is very
simple in rank order to find the less noisy channels
because they are in the left part of the graph.
The marker is always active rotating the knob.
Pressing the knob the graph changes between rank
order to channel order again.
For terminating the SCAN function, press the lower
button on the right of the display.
In the above picture a typical graph of the scan func
-
tion (only the graph area of the display). This graph,
ordered by channel numbers, shows the RF levels in
dBµV for each channel in the selected group (i.e. Ch:
00). Rotating the knob the small arrow cursor moves
from a channel to the next one; on the right of the
graph it is possible to see the rank of the channel
selected by the cursor, its number, its frequency
and the RF level. Pressing the knob the order of the
graph became the rank, not the channel number. In
this way it is more simple to choose channels with
lower RF noise, they are in the left part of the graph.
See at the picture below:
In this graph the channels are ordered by rank. Turn
-
ing the knob it is possible to change the channel and
reading its number, frequency and level of RF noise.
The horizontal dashed line is the squelch level set
before starting the scan.
Connecting an headphone at the monitor output, is
possible to ear the signal in the channel selected by
the knob. If the RF signal is below the squelch level,
the upper button near the display disable/enable the
squelch so the audio output is enabled also for weak
RF signal.
The SELECT button is the exit from the SCAN func
-
tion tuning the receiver on the selected channel, the
EXIT button exits from the SCAN function leaving
the receiver channel unchanged.
