Dtmf (Touch-Tone) Features - Radio Shack HTX-242 Owner's Manual

UNDERSTANDING THE НТХ-242
This section explains some of the HTX-242's features. See "Basic
Operation" on Page 16 for instructions about how to use these fea-
tures.
Dual VFO Modes
The VFO (Variable-Frequency Oscillator) modes let you directly
select a frequency anywhere within the HTX-242's operating range.
Your HTX-242 has two VFOs: VFO-A and VFO-B. You typically use
the VFOs to tune to frequencies you have not stored into one of the
HTX-242's memory channels (see "Memory Channels" on Page 13).
A related feature of the HTX-242 lets you transmit on the fre-
quency selected with one VFO and receive on the frequency
selected with the other VFO. (See "Using the Dual VFOs for Duplex
Operation" on Page 27.)
DTMF (Touch-Tone) Features
DTMF (Dual-Tone, Multiple Frequency) is another term for touch-
tones (the tones a telephone produces when you press a digit). This
standard set of tones is used by many different amateur radio sys-
tems for accessing programmable features and dialing through
autopatches.
Your HTX-242 produces all 16 standard DTMF tones (0-9, *, #, A,
B, C, and D). It has 10 DTMF memories which can each hold up to
15 digits for quick transmission. You can also set the HTX-242 to
listen for a specific set of DTMF tones, and alert you when it
detects them (this feature is called DTMF Paging). Until it hears the
sequence, the HTX-242 does not pass any transmissions to the
speaker.
Group Calling lets you DTMF page a single person or an entire
group of people. To use group calling, every person in the group
selects the same first three digits as their DTMF page sequence.
They then select up to four additional digits unique to each person.
То page an individual, you transmit their entire DTMF page
sequence. To page the entire group, you transmit at least the first
three digits of the sequence, followed by the DTMF tones for A, B,
and C.
Note: Group Calling only works with the HTX-242 and other transceivers
that support this feature.
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