Kenwood TH-55AT Series - Manual (Page 16)

3-6 REPEATER OPERATION
3-6-1 TRANSMITTER OFFSETS
All amateur radio repeaters utilize a separate receiver and
transmitter section. The receiver frequency may be either
above or below the transmitter frequency.
For most repeaters offsets are as follows:
\ Modal
оьД
Ptey \
TH-25A
TH-25AT
TH-25E
TH-45A
TH-45AT
TH-45E
TH-55AT TH-55E European
version
UK.
version
-1- + 600kHz + 5MHZ + 1.6MHz + 12MHz + 36MHZ
-600kHz -5MHz -1.6MHz -1.6MHz -12MHz -6MHz
-7.6MHz
• Offset Direction
To select the desired transmitter offset direction press the
SHIFT key. Each time you press the key the transceiver will
advance from one offset to the other, i.e. + to S
( to 1^ with TH-45E European version) to no offset
(simplex).
The transceiver allows you to store the frequency, offset in
memory, or you can select these functions directly from the
keyboard.
•
• Auto-Offset {TH-25AT only)
The TH-25AT has been programmed according to the stan­
dard ARRL Band Plan, regarding transmitter offsets. Please
see the accompanying chart for additional information. You
can, of course, override this by using the SHIFT function, if
desired.
144.00 145.10 146.00 146.60 147.40 148.00
- S - P S - - F S - S
S: Simplex Channel 145.50 146.40 147.00 147.60
3-6-2 REVERSE FUNCTION
Some repeaters utilize a “Reverse pair", i.e. the trans-
mit/receive frequencies are exactly the reverse of another
repeater. For example repeater A uses 146.000 for a
transmit frequency (OUTPUT) and 146.600 for receive
(INPUT). Repeater В uses 146.000 for its receive and
146.600 for its transmit frequency. It would be inconve­
nient to have to reprogram the transceiver each time if you
were in range of both repeaters.
The REV key allows you to reverse the transmit and receive
frequencies. To use the REVERSE function press the REV
key. The offset indicator ( ■+■ or s / s or S ) will
flash OFF and ON in the display to remind you that you are
working a reverse repeater pair.
To return to normal offsets press the REV key again. This
function is also useful to check the input frequency of the
repeater, so that you can determine if you are within
SIMPLEX communications range.
3-6 3 TONE OPERATION
Some repeaters require the use of a control signal to activate
the repeater. Several versions are currently in use
worldwise.
In the United States sub-audible tones are sometimes used.
With the TH-25A/25AT/45A/45AT/55AT 37 different sub-
audible tone frequency selections are possible with the use
of the optional sub-audible tone encoder/decoder (TSU-6).
This accessory also allows for CTCSS (Tone Squelch) opera­
tions. When this option is activated the squelch of the
transceiver will only open when the proper sub-audible tone
is received.
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