Originally Posted by tchartney
... OKWIN. When I scan the 800 Freq for my area I pick many agencies on the same freq. So now I want to be able to program these agencies so I can only here select ones how do I know what freq they belong to. Third question is does my scanner pick-up EDACS if yes then how do I put them into my scanner. Last and final question (for now), how do i get it to scan Trunk for one bank and what I call regular freqs (154.3700) in another bank and be able to pick up both. Thanks in advance.
OKWIN - The various agencies are not on particular freqs., they have particular TALK GROUPS and they all share all the freqs. A master computer chooses a freq. every time someone pushes their mic button. I will put a simple explanation at the end of this page, using Motorola trunking, the most common type.
EDACS - You need to put in all the frewqs. for a particular site. Each freq. MUST be in an exact channel in your scanner. The channel numbers are the small numbers in front of each freq. in the database..
The object of trunking is to allow many users to share a relatively few frequencies.
A trunking system is controlled by a computer. Information (data) is exchanged between the system radios and the computer on a control channel, sometimes called a data channel. It sounds like a strong buzz.
A large system can have up to 28 freqs., 4 of which may be used as control channels. The control channel may be changed once a day or as often as the programmer decides. Some scanners need only the control channels to track an entire system. Just put in the 4 Control Channels.
Each group of users (Fire, Police, etc.) is assigned TALK GROUPS. In a Motorola Type II system, the most common type, TGs are usually in 32 number steps starting with 16 and going up to 65536; 16, 48, 80 --- 4656, 4688, 4720 --- 28944, 28976, etc. System radios can have more than 100 TGs programmed into them.
After all the freqs. have been entered and it is "trunking", the Banks become SCAN LISTS where you enter the Talk Groups you want to hear. Use the Talk Group numbers in the DEC column.
When a user pushes the talk button on his radio, data is sent to the computer. The computer chooses an unused freq. and sends that data to all the radios using the TG of the originating unit. This all happens in a fraction of a second and it happens EVERY TIME a radio is used.
Fire Dispatch calling Engine 4 (TG 4528 on 856.7125)
Engine 4 answering Dispatch (TG 4528 on 852.2625)
Respond to 73 Elm Street (TG 4528 on 855.9625)
Engine 4 responding (TG 4528 on 851.6375)
If you have entered TG 4528 into your scanner, it will decode the control channel data and change your scanner freqs. to follow the conversation on TG 4528.