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Upgrading Uniden Firmware

26 Mar

In an earlier posting about unit IDs, I mentioned that you needed the latest version of the scanner firmware in order to take advantage of that feature. Here’s the applicable websites with instructions for updating your firmware and enabling unit IDs:

BCD396XT: Firmware Upgrade

BC346XT: Firmware Upgrade

BCT15X: Firmware Upgrade

Add the unit IDs to your scanner the same way you would a new Talkgroup (to make the “i”, press the decimal key).

To view unit IDs on a P25 system, program it in as P25 single frequency trunk.

Good Luck!


Unit IDs

25 Mar

If you have a newer Uniden scanner, like the BC346XT or the BCD396XT and have upgraded to the latest firmware, you can enable the scanner to show Unit IDs on trunked and P25 systems. Here’s what that means:

Trunked systems are essentially computer controlled, and every time a user keys their radio, information is transmitted throughout the system, including an ID associated with that specific radio. Newer scanners can decode that information and display it. Knowing what radio is being used can be amazingly helpful while scanning. A few of the systems that you can see this on in the Boston area include the Massachusetts State Police, Cambridge PD/FD, and MassPort.

All of the marked and semi-marked MSP cruisers have an ID number on the license plate, and on the fender of the marked cruisers. If you’re listening to them on the scanner, this is the “call sign” that they are using, for example “2133 to Station A” would be the trooper operating this car:

For troops A, C, D and H (and maybe B), this number is also used as the ID (prefaced by a “5”) for the radio installed in the car itself. So, while I’m hearing that transmission, my scanner is also displaying UID:i52133. So even if I didn’t hear the beginning of the transmission, I can still see that and know which unit is calling. Each trooper also has an ID number, which is separate from his cruiser number. Sometimes you’ll hear them use their ID number on the radio when they are calling in to book a report, and they always give it at roll call. These numbers are used as the ID (prefaced by a “4”) for the portable radio (the “walkie talkie” that the trooper carries on his belt. If the trooper above, whose ID is 2588, gets out of his car and uses his portable, the display on my scanner shows UID:i42588. Since I don’t want to be looking up 2588 every time, I can program that ID into the scanner so it displays something simpler, like “Cruiser 2133”.
E Troop (Mass Pike) cruiser numbers are 2 or 3 digits followed by an “E”, for example, 120E. The ID numbers for the radios installed in the cruisers all start with a 3, and do not correlate to the cruiser number. For example, 120E is i35946. The portable radios follow the same convention the other troops use, though, so 120E is operated by trooper ID 1670, with portable radio ID i41670.
F Troop (Logan Airport) very rarely operates on the MSP trunked system, and are actually dispatched on the Massport system.
It can take a lot of listening to put together a thorough list of unit IDs for a single system. Besides the multiple radios used by each officer, you have the radios at the barracks, on air wing units, marine units, DCR Rangers, MEMA, etc. It can be very rewarding, though, especially if you like to know a little more detail about what is going on. 
If this is the sort of thing that you think might interest you, the Uniden BC346XT and BCT15X are good units that are priced towards the lower end of the spectrum. If you pick up one of these scanners, or if you have had one and just need help programming it, let me know and I’ll gladly put together a programming file for you.
As always, post questions, comments, and concerns and I’ll get back to you.

Squelch Tones, Simplified

22 Mar

Did you know that besides just the voice you hear, many radio frequencies carry additional information that you can’t even hear? The most common example of that is a squelch tone, more officially known as CTCSS, CDCSS, DPL or DCS. I’m not going to get into the technical details of how these work, but I’ll give a real world example of how this affects you when you’re scanning.

One of the more active Fire Buff radio networks in Eastern Massachusetts is Fire Radio Systems, which operates on 461.4000. If you have a scanner that doesn’t support CTCSS codes and you program in that frequency, you may also hear one of the other area organizations that share that same frequency, such as Bass Pro Shops in Foxboro, the New England Science Center in Worcester, or the First Church of Christ, Scientist, in Boston.

None of these groups want to hear the others’ radio traffic, so each group’s radios are programmed with a different squelch code. In the case of FRS, the radios are programmed with a code of 136.5. The same code is sent along with each transmission, and any transmissions that don’t have that code won’t be heard.

Most newer scanners also support these codes. In addition to screening out unwanted traffic when programmed in correctly, if left unprogrammed, they will also display the code that is being used, which can help you identify unknown frequencies or users. If your scanner doesn’t support this, it’s probably time for an upgrade. I use the Uniden BC346XT and the Uniden BCD396XT. The GRE PSR-310 is a popular choice, as well.

Post any questions in the comments below and I’ll try and answer them as best as I can.