Trunking | Scanner Master Blog

ScannerMaster offers a service to install the various paid updates for Uniden HomePatrol, x36 and P2 series scanners. These updates include the HomePatrol Ultimate Update (for HomePatrol 1 and 2 scanners) as well as the ProVoice and DMR/TRBO updates for the BCD436HP, BCD536HP, BCD996P2 and BCD325P2 scanners.

If you buy one of these scanners from ScannerMaster we offer a service to install these options for you before we ship the scanner. You can also send the scanner to us to perform the update, we then send the radio back to you.

Sometimes however it is not practical to send the radio to us. For US and Canadian customers it is pretty simple to buy the update directly from Uniden and install it yourself. For customers in other countries however it is a different story. Uniden can only accept credit cards from US and Canadian addresses. If you live in other countries then Uniden cannot accept your credit card for payment for these updates. They will refer you to a third party like ScannerMaster to obtain your updates.

ScannerMaster can accept credit cards from most countries. As long as the card works on our payment system we can provide you with the secret code to unlock the update for your radio. There are a couple things you will need to do to make this all work out:

First you need to update the FIRMWARE for your scanner. This is so important that if you don’t do it the paid updates just will not work! On the HomePatrol and x36 scanners it is done thru the Sentinel software, on the 325 and 996P2 radios it is done thru a separate (free) program available from Uniden’s website.

Once you have done the Firmware Updates then you need to obtain the “ESN” (Electronic Serial Number” from your scanner along with the “SUM” code. Here are the procedures for this:

HomePatrol-1 and HomePatrol-2:

Press Menu
Press Advanced Menu
Press the down arrow to get to the second page of items
Press the Version Information Button.

The ESN is listed and starts with 36 for the HP-1 and 37 for the HP-2. The SUM Code is the last 3 digits past the second dash. The ESN will look something like 36327-0040012345-123, the SUM code is the “123” part.

BCD436HP, BCD536HP, BCD325Ps and BCD996P2:

Press Menu
Select Settings.
(If you do NOT see “Upgrade” as an item in the list go back and update the firmware and start over!)
Select See Scanner Information
Select Firmware Version
The ESN will be listed as “SN37……”
The SUM Code will be a 3-digit letter/number combination.
We need both the ESN and the SUM Code. Don’t worry about the M-VER code.

We need the complete ESN and the SUM Code as well as the model of radio you have. With this info we can obtain the one-time code that unlocks the feature you want and send that code to you. You then go to the Upgrade menu on your scanner and enter it using the rotary knob to select the numbers. Once the code is properly added the radio will think it over for a minute or so and then announce that it was successful.

Once properly updated the code will stay working on the radio and will not need to be reinstalled. The code will only work for the radio it was obtained and if you dispose of the radio there is no way to transfer the code or feature to another radio.

In the old days of scanning things were pretty simple, you put in the local police frequency to listen to the police. In many parts of the country however, this no longer works. Most cities, many counties and even entire states use Trunking Systems. What are trunking systems and how do they work?

The best way to explain how a trunking system works is the analogy of a set of bank teller lines. The bank has 5 tellers, you can line up at any of the 5 lines and hope your line goes faster than the others. Then you get stuck behind the lady that wants to have her penny jar counted by hand…

These days however, banks have a single queue and you go to the next available teller when you reach the head of the line. This is exactly how a trunked radio system works: All users are in one queue and get assigned the next available channel. Instead of having a separate frequency for the FD, one for the PD and another for the ambulance, they just go to the next channel that isn’t being used.

All this is controlled by a computer system called, appropriately enough, a “Controller”. The Controller watches the system and when a radio requests to talk it assigns that radio and any other radio in its group to a channel. All this happens in a fraction of a second.

Radios have all the frequencies used by the system programmed into them and the system is broken down into various virtual channels, called “Talkgroups”. Talkgroups are assigned to various uses like channels would have been before. For example, Mayberry PD might be assigned Talkgroup 101 for Dispatch, 102 for Car-Car and 103 for Detectives. Mayberry FD might be assigned Talkgroup 123 for Dispatch, 124 for Fireground and 125 for Tactical. If Mt. Pilot is sharing the system they might be assigned Talkgroup 287 for Police Dispatch and so on.

There are several types of trunking systems but they all work in much the same way. There are differences in the way they get programmed into scanners as well. The main types of trunked systems in use by Public Safety agencies in the USA include Motorola, EDACS, LTR, APCO25 Phase 1 and APCO25 Phase 2.

For scanner listeners these trunked systems add a layer of complexity to the programming. Depending on the type of scanner and the type of trunked system the method used to program differs. For newer Unidens you program in a “System” to identify the type of trunking, then “Sites” to put in the frequencies used and lastly “Groups” for the talkgroup listing. Whistler, GRE and Radio Shack scanners with Object Oriented programming work differently. On LTR and EDACS systems you have to identify the proper “LCN” channel numbers, these are usually well documented at www.radioreference.com. Motorola and APCO25 systems do not need the frequencies in any particular order.

HomePatrol and other scanners with the Database feature will have these Trunked System parameters already programmed so you can just select the Service and location to listen to them. They do all the heavy lifting for you.

Keep an eye on the ScannerMaster Blog for our explanation of Digital operations!