PAGE 68 AR5000 OPERATING MANUAL
Note: When the CTCSS search is active it is not possible
to toggle the frequency display and text display. If the
optional CT5000 board is not fitted the above procedure
will result in no audio being produced.
16-4 CTCSS SQUELCH
The CTCSS tone squelch facility assumes that you either
know the frequency required or you have already used
the CTCSS SEARCH facility to identify the required tones
for specific transmissions.
When this facility is engaged only the selected CTCSS
modulated signals can be received. No audio will be
heard from other transmissions even if the radio has
received a strong signal (which does not carry the selected
CTCSS frequency).
1 To access the CTCSS menu press
. Use
the
keys to access the CTCSS menu, the
LCD legend “
CTCSS
CTCSS
CTCSS
CTCSS
CTCSS
” confirms selection.
DE-SCR OFF
(if DS8000 option is fitted)
CTCSS OFF <<<
CTCSS OFF <<<
CTCSS OFF <<<
CTCSS OFF <<<
CTCSS OFF <<<
DTMF OFF
T-ELMT OFF
2 The
SUB DIAL
is used to make selection of CTCSS
operation “
OFF
OFF
OFF
OFF
OFF
”, “
ON
ON
ON
ON
ON
” or “
SRCH
SRCH
SRCH
SRCH
SRCH
”. Rotate the
SUB DIAL
to select “
ON
ON
ON
ON
ON
”.
3 Press the
key to advance to the tone select
menu.
4 The
MAIN DIAL
or
SUB DIAL
may be used to select the
required CTCSS frequency, frequencies ascend in three
popular groupings then loop back to the beginning (refer
to the CTCSS frequency table at the beginning of this
section).
5 Press
to accept the displayed value (or to abort
entry press
). The legend “TONE” on the top line
of the LCD confirms selection of CTCSS tone squelch.
When transmissions are encountered containing the
selected CTCSS frequency, normal reception will be
established with the squelch opening and closing in the
normal manner.
6 To toggle the current selection ON/OFF press
(select the CTCSS menu)
Note: If the optional CT5000 board is not fitted the above
procedure will result in no audio being produced.
(17) Optional I.F. filters (500 Hz, 2.5 kHz
& 5.5 kHz)
It is possible to add an additional (optional) high quality
500 Hz seven resonator Collins mechanical filter for
improved selectivity when monitoring CW and other data
modes. Optional eight resonator Collins mechanical filters
may also be used in place of the standard fitted 2.4 kHz
(3.0 kHz) and 9.0 kHz (5.5 kHz) filters.
500 Hz MF500 Collins 526-8693-010
2.5 kHz MF2.5 Collins 526-8694-010
5.5 kHz MF6.0 Collins 526-8695-010
17-1 Fitting the optional 500 Hz filter
Only the upper case of the AR5000 needs to be removed
when installing optional filters. Switch the receiver off and
unplug the power cord.
1 In order to lift the upper case, carefully (with the correct
fitting posi-drive screwdriver) remove the 4 screws from
the top cabinet and the 3 screws from each side panel
(the screws on the side of the unit toward the front are
larger than the rest). The rear edge of the top cabinet
has a flange and the sides have two unused holes (for
mobile mounting).
2 On the top-rearmost PCB (I.F. board), disconnect the
IF OUT connector J8 (PCB side) from the socket on the
rear-left of this board and remove the six board fixing
screws.