Freedom R8100 SERIES, Operator'S Manual

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Choose from the available decoding functions on a horizontal menu. These include PL/Period Counter,
DPL Decode, DTMF Decode, 2-Tone Decode, 5/6 Decode, and General Sequence.
PL/Period Counter – Displays the frequency and numeric code of the recovered audio from a radio
modulated with the Motorola Private-Line (PL) format (Figure 2.2.5.4-1). The period counter allows
rapid high resolution measurements of non-PL low frequency modulation without the long gate times
associated with frequency counting. A vertical submenu provides adjustment of the Low and High Pass
filters to reduce noise for more accurate measurements. Recommended filter settings for PL: HP= 1 Hz;
LP = 300 Hz.
Figure 2.2.5.4-1 PL/Period Counter screen
DPL Decode – Provides a numeric code readout from the recovered audio of a radio modulated with the
Motorola Digital Private-Line (DPL) format (Figure 2.2.5.4-2). A vertical submenu provides adjustment
of the Low and High Pass filters to reduce noise for more accurate measurements. Recommended filter
settings for DPL: HP= 1 Hz; LP = 3 kHz.
Figure 2.2.5.4-2 DPL Decode screen
DTMF Decode – Decodes DTMF (Dual Tone Multi Frequency) signals used in testing telephone
interfaced systems (Figure 2.2.5.4-3). A vertical submenu provides adjustment of the Low and High Pass
filters to reduce noise for more accurate measurements. Recommended filter settings for DTMF: HP= 1
Hz; LP = 3 kHz. Note: The R8100 displays the history of previously decoded DTMF codes, with the
right-most code digit being replaced by the most recently decoded tone. The DTMF Code field appears
static when the transmitted code isn’t changing or nothing is being decoded. Press the Reset soft key to
clear the history.
Figure 2.2.5.4-3 DTMF Decode screen
2-Tone Decode – Decodes the two-tone sequential paging format. The meter displays the Tone A/Tone
B (Tone 1 and Tone 2) frequencies and durations (Figure 2.2.5.4-4). A vertical submenu provides
adjustment of the Low and High Pass filters to reduce noise for more accurate measurements. The Decode
soft key is used to start or stop decoding. Recommended filter settings for 2-Tone decode: HP= 1 Hz; LP
= 3 kHz.