Radio Shack PRO-2050 owner manual Scanning Type I and Hybrid Trunked Systems

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To remove a scan list from active scanning, use the number keys to en- ter the scan list’s number. The scan list indicator turns off, and the IDs in that list are not scanned.

Note: You cannot remove all the scan lists. One scan list must always be ac- tive.

To restore a scan list to active scan- ning, use the number keys to enter its number again.

Press SEARCH to return to the scan- ner’s previous function.

SCANNING TYPE I AND HYBRID TRUNKED SYSTEMS

Your PRO-2050 is set to scan Type II user IDs by default. When you scan trunked frequencies, each Type II user ID you see appears as an even num- ber without a dash (such as 2160). Your PRO-2050 can also scan Type I trunked systems. Each Type I ID ap- pears as a three- or four-digit number, followed by a hyphen, followed by a one- or two-digit number (such as 200-14).

If you notice a mix of odd- and even- user IDs (such as 6477, 2160, 6481, 6144, and 1167), then you are proba- bly monitoring either a Type I or hybrid (a combination of Type I and Type 2

user IDs) system. (See “Types of Trunking Systems” on Page 25.)

You might also notice that you are missing responses when you hold on an active ID. Unlike Type II systems, Type I and hybrid systems require a fleet map that sets specific fleet-sub- fleet parameters. It is easy to select a fleet map to scan; what is not always easy is selecting or programming a map that is being used in your particu- lar area.

When a Type I system is designed, the address information for all its user IDs is divided into 8 equal-size blocks, numbered 0–7, and each block is as- signed a size code. When you set up your scanner to track a Type I system, you must choose a size code for each block. When you have chosen a size code for all 8 blocks, you will have du- plicated the fleet map for the system you are tracking. If you have chosen correctly, you will be able to track transmissions in that system.

Each size code defines the number of fleets, subfleets, and IDs each block has. For example, you can see in the following table that a size code of S4 has one fleet, which is divided into 16 separate subfleets, and it has a total of 512 individual IDs.

Size	Fleets	Sub-	IDs	Block
		fleets		Used
S0	Reserved block for Type II IDs
S1	128	4	16	1

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