Frequency/Trunk List Legend
I usually format my frequency lists the same way. The format I use is demonstrated below with an explanation of how to read it.
179.9 153.860/158.955 *CITY of Pearland EMS Dispatch (STAR-Net trunk 13808)
The first number is the PL or DPL tone used (if any). If the number has a decimal point, it is the PL (CTCSS) frequency in Hz.
If it is just three digits, it is the DPL (some call DCS) code.
The next number (in this case 153.860), is the (repeater) output frequency in MHz. This is what you would typically program into a scanner to receive the base and mobiles.
Since it has a second frequency after the "/", this indicates that it is a repeater system as opposed to simplex.
The frequency after the "/" (158.955) is the repeater input frequency in MHz. This is what the mobiles actually transmit on when using a repeater but you would be better off listening on the repeater output frequency to hear everybody.
There are a few exceptions to this whereas someone may operate "half-duplex". Many taxi companies and some Texas DPS channels operate where the base is on one frequency and the mobiles are on another but the mobiles are not repeated through the frequency used by the bases.
The next field indicates the service, agency, and sometimes other information.
In this case, it shows that the city of Pearland EMS operates on the STAR-Net trunked system and uses talkgroup 13808. The audio from the talkgroup can also be heard on 153.860 MHz.
Sometimes, a channel number may be indicated. On some aviation frequencies, the UHF (of VHF) counterpart may be listed.
In many of my lists, I use certain letters and terminology whose meaning may not be that obvious.
In this file, I hope to explain the meaning of these so that the information they provide will be more useful.
- * - confirmed/usually used next to a frequency or talkgroup to indicate that I have heard activity on it and
that any description I have listed next to it should be correct
- d - marked for deletion/usually in frequency lists/information is either obsolete, never confirmed, or
was incorrect to begin with
- = - in Amateur Radio list means this repeater is not listed in the current ARRL repeater directory (new
or just not listed
- # - in Amateur Radio list means this repeater was dropped from the last ARRL repeater book I referenced
- | - in Amateur Radio list means this repeater has been dropped from last two ARRL repeater books
- c - control channel/used as one of four possible control channels for a trunked radio system.
Sometimes, I also put a number in front to indicate the order of use that the control channels will be used.
i.e., a "1" means that it is most likely to be the control channel, to "4" being the least likely.
- i - frequency used to ID a trunked radio system in Morse Code
- p - frequency used as interconnect (phone patch) in a trunked radio system
- k - key click/In a trunked radio list, I use this next to a frequency when I've heard the
frequency with a brief, silent transmission. This usually means that the frequency is part of a
trunked radio system and may be used on an as-needed basis when the system starts getting "busy".
LTR channels commonly key-up with no audio but I use this letter in the case of Motorola trunked systems.
- pc - frequency used for private call feature in a trunked radio system/some trunked systems set aside certain
frequencies for private calls
- dvp - frequency used for DVP (digital voice protection-scramble)/many trunked systems with DVP
capability set aside certain frequencies for DVP usage
- In an EDACS or LTR trunked radio system list, the numbers in the parenthesis indicate the LCN or
logical channel number. When programming a trunk-capable scanner, it is neccessary to program the
channels in this order to properly track the system.
- In Motorola talkgroup lists, I list the hex value of the talkgroup (minus the LSB) along with the Uniden (scanner) value.
This is usually only meaningful to people using computer software to track trunked radio systems
or for people programming 2-way radios. If you only use a scanner, it won't be of any use to you.
- For EDACS talkgroup lists, I list the decimal value of the talkgroup along with the AFS (Agency-Fleet-Subfleet)
value. Some scanners will let you use either type format. I like to use AFS format myself since
the numbers are more meaningful and helpful in figuring out unknown talkgroups.
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