AR5000 OPERATING MANUAL PAGE 27
3. Press
to accept the changes,
to abort
or
to move on to the audio internal / external
selection.
6-12 Audio tone eliminator (T-ELMT)
Various utility radio users are permitted to transmit their
signals with an accompanying continuous tone (pilot tone)
which is over ridden by the operator’s audio (voice). This
type of tone is transmitted continuously in order to provide
advanced security for radio communication system and
to ensure that important radio links are in working order.
The AR5000 tone eliminator is used to eliminate many of
these tones to enable the squelch to close when in scan
& search modes preventing the AR5000 locking up on
unwanted busy channels.
VFO, memory, scan & search
The tone eliminator may be programmed independently
into each VFO, memory channel and search bank for
greatest flexibility, this prevents the scan and search
process from halting on unwanted signals... when the tone
eliminator is registered with a memory channel or search
bank, the scan & search process will ignore (skip) busy
frequencies which carry the specified tone frequency.
Selecting the required tone eliminator frequency
1 The tone eliminator is selected from the OPTION menu.
Press
to access the menu then use the
and
keys until the display shows “
T-ELEM OFF
T-ELEM OFF
T-ELEM OFF
T-ELEM OFF
T-ELEM OFF
”
(one press on the
key, the sequence will change if
the DESCRAMBLER or CTCSS options have been
installed).
DE-SCR OFF
(if DS8000 option is fitted)
CTCSS OFF
(if CT5000 option is fitted)
DTMF OFF
T-ELMT OFF
T-ELMT OFF
T-ELMT OFF
T-ELMT OFF
T-ELMT OFF
<<<
2 Rotate the
MAIN DIAL
or
SUB DIAL
while listening to the
received audio (which contains the unwanted tone) until
the “BUSY” legend has disappeared, this indicates that
the tone has been eliminated and will be ignored by the
receiver. It is sometimes best to rotate the DIAL so that
the “BUSY” legend flutters half way between the signal
disappearing and reappearing. The
key is used
as a short cut to OFF. The acceptable range is 1 ~ 255
and OFF.
Signal processing is carried out by an analogue system
so some variation should be allowed from set to set. The
following tones may be eliminated (approximate range is
0.4 kHz (400 Hz) to 4.4 kHz):
Unwanted tone
Suggested setting
0.4 (kHz)
0 ~ 31
0.5
50 ~ 81
0.6
88 ~ 113
0.8
136 ~ 155
1.0
165 ~ 179
1.2
184 ~ 196
1.4
198 ~ 208
1.6
208 ~ 217
1.8
216 ~ 223
2.0
223 ~ 228
2.2
228 ~ 233
2.4
232 ~ 236
2.6
235 ~ 239
2.8
142 ~ 245
3.0
244 ~ 247
3.2
247 ~ 249
3.4
249 ~ 251
3.6
247 ~ 250
3.8
249 ~ 251
4.0
251 ~ 252
4.2
252 ~ 253
4.4
253 ~ 254
3 To complete the sequence and accept the input press
Note: There is no on-screen indicator to show that the
tone eliminator has been programmed (when outside of
the tone eliminator selection menu).
The tone eliminator only effects the way in which the
squelch interprets activity, tones are NOT removed from
the received audio presented to the operator... i.e. you
will still here the tone but the “BUSY” indicator can be
programmed to extinguish as if the squelch has closed.
Tone alone
= treated as channel unoccupied
Tone & voice
= channel busy