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Revision as of 15:21, 11 June 2012 by Plaws (Cleanup - Interim save)
Type II Talkgroup Conversions
The easiest way to convert talkgroups between their various formats is by using the Windows scientific calculator. It provides a Decimal to Hex function that works very well.
Marshall Sherard, KE4ZNR, has a talkgroup converter that can be used to convert between the various formats of talkgroups.
All Motorola Type II talkgroups are evenly divisible by 16.
Type II talkgroup IDs come in three flavors:
- Uniden Trunktracker format, e.g. 41072 (Range: 0 - 65504)
- Motorola 3 digit hexadecimal, e.g. A07 (Range: 000 - FFE)
- Motorola 6 digit decimal, e.g. 802567 (Range: 800000 - 804094)
In the following formulas, M3 represents a Motorola 3 digit Hex format value, M6 represents a Motorola 6 digit decimal format value, and U represents a Uniden format value.
- The notation Dec_to_Hex(X) means convert X to its Hex equivalent.
- The notation Hex_to_Dec(X) means convert X to its Decimal equivalent.
To convert Use this Formula
- M6 to U (M6 - 800000)*16 = U
- M6 to M3 Dec_to_Hex(M6 - 800000) = M3
- M3 to U Hex_to_Dec(M3)*16 = U
- M3 to M6 Hex_to_Dec(M3) + 800000 = M6
- U to M3 Dec_to_Hex(U/16) = M3
- U to M6 U/16 + 800000 = M6
- Convert the M6 format ID, 802617 to U format:
(802617 - 800000)*16 = 41872
- Convert the M6 format ID, 802617 to M3 format:
Dec_to_Hex(802617 - 800000) => Dec_to_Hex(2617) = A39
- Convert the M3 format ID, A39 to U format:
Hex_to_Dec(A39)*16 => 2617*16 = 41872
- Convert the M3 format ID, A39 to M6 format:
Hex_to_Dec(A39) + 800000 => 2617 + 800000 = 802617
- Convert the U format ID, 41872 to M3 format:
Dec_to_Hex(41872/16) => Dec_to_Hex(2617) = A39
- Convert the U format ID, 41872 to M6 format:
41872/16 + 800000 = 802617
APCO-25 Talkgroup Conversions
To avoid confusion, it should be noted that APCO-25 system talkgroup IDs are also displayed in multiple formats: decimal (e.g., "26570") and hexadecimal (e.g., "675c"). To convert between the two formats, simply perform a straight hex-to-decimal conversion (or decimal-to-hex conversion), again using the Windows scientific calculator or one of the many free conversion calculators available on the Internet.
Type II Special Status Bits
Type II systems use these status bits for special transmissions such as Emergency, Patches, DES/DVP scrambled transmissions, and Multiselects on Motorola Trunking systems. Motorola Trunking radios directly interpret them for their special functions, thus no difference is noticed by the person with the radio. The Trunktracker scanners however interpret these special talkgroup status bits as different talkgroups entirely. Below is the conversion chart for these special status bits.
|TTID + #||Usage|
|ID+3||talkgroup patch to another|
|ID+7||Multi-select (initiated by dispatcher)|
|ID+8||DES Encryption talkgroup|
|ID+9||DES All Talkgroup|
|ID+11||DES Talkgroup patch|
|ID+12||DES Emergency Patch|
|ID+13||DES Emergency multi-group|
|ID+15||Multi-select DES TG|