Operating instructions

LOCAL OPERATION
3-76
The underlined tones are listed in the center of the display with an analysis of the parameters of
each tone as below:-
• The measured frequency of each tone.
• The percentage error from the true tone frequency.
• The duration of each tone.
By using the [ E ] or [ F ] keys, the analysis of all tones in the decoded sequence can be shown.
The stored sequence can be cleared from the store by pressing the [Clear Sequ] key.
Revertive tones
Revertive tones signaling takes various forms. The common factor is that a tone sequence
received by a mobile transceiver or other receiver, will trigger a second sequence to be returned.
The second sequence may be a duplicate of the first or a different sequence. It can be used to
modulate a signal on a reverse channel or on a different channel. For some applications either or
both of the tone sequences may be used as an AF signal.
The routing of the original tone signal out of the Service Monitor, and the revertive tone signal
into the Service Monitor, is dependent on the settings of the [Tones In] and [Tones Out] keys on
the TONES selection screen. This allows the permutations shown in the following table.
Original tones out Revertive tones in
RF RF
RF AF
AF RF
AF AF
The revertive tones operation is configured by pressing the [Revertv Tones] key. To send a tone
burst, do one of the following:-
• If
TONE BURST has NOT already been selected as the send mode, press the [Send Mode] key
to access the send mode menu, then press the [Tone Burst] key. The tone sequence will be
generated, then after the last tone, the Service Monitor will change to decode mode ready to
decode the revertive tones.
• If
TONE BURST has already been selected as the send mode, press the orange [ON/OFF]
function key. The tone sequence will be generated, then after the last tone, the Service
Monitor will change to decode mode ready to decode the revertive tones.
The encoder screen can be displayed again by pressing the
[Encode] key.