Spectra Logic TAC/COM SERIES - Manual (Page 92)

Tac/Com Control Head Manual SM06 Rev. 4.10
The additional codes and frequency display were added in the new control head
software in 1991 for USFS/OAS contracts. Tone data is often received in the EIA
sequential number format, or as the raw frequency, and requires additional tone support
for ease of use. Controls with USFS interfaces (guard controls) are set for the EIA
sequential tone code at the factory. Older controls (pre-1991 Tac/Com II) may upgrade
to current generation software for this expanded tone display.
3.5.4.3
Using Help to Get the Table
The tone code table is accessed by pressing HELP while editing a tone location during
channel editing. Scroll through the table by pressing HELP until the desired entry is
located. Press RADIO to exit, or continue through the table by pressing HELP until the
data entry screen is reached.
3.5.4.4
DPL Codes
NAT NT-series transceivers support 83 Digital Private Line Codes (DPL) in addition to
the CTCSS or Private Line subaudible tones. This option must be enabled at installation
time in the installation and configuration mode of operation. It is normally shipped set to
OFF by the factory to reduce confusion over tone codes.
DPL codes are three digit sequences that describe a digital code sent at low frequency
in the background of regular transmissions. They are filtered out of normal receive
audio and provide another method of signalling or squelch control.
Code numbers are arbitrary and are stored in an internal table. When in use, the
control head finds the correct entries based on how the code is entered. The FREQ
option for tone presentation is not available if DPL is enabled.
023 DPL Code If the '0' position is chosen for edit, the control head is
programmed to select a 3-digit DPL code and bring up the
table for the SELECT switch to choose from.
32 Tone Code If the first digit position is skipped, the control head is tone
code programmed to select a 2-digit CTCSS tone code and
bring up the table for selection.
This arises ONLY if DPL is enabled. For most users, this selection will not be used
because only subaudible tones are used.
Page 3-18 Jan 4, 2006
ENG-FORM: 806-0106.DOT
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