Latest Posts
Paul O’Grady
29 March 2023
Radiodays Europe 2023
28 March 2023
Podcast Series Made by AI
23 March 2023
21 March 2023

Review: Whistler TRX-2 Digital Scanner


Tim Kirby takes an in-depth look at the Whistler TRX-2 Multi-System Adaptive Digital Trunking Scanner in the UK Band Plan technical configuration supplied by Moonraker

It was another of those emails from our dear editor. Would I like to have a look at the Whistler TRX-2 desktop digital scanner, with the setup as supplied by Moonraker? We’ll come to the difference that means shortly. 

I’d heard great things about the Whistler scanners from various friends and I was keen to try it. 

So, what basic information is available online about this radio? Here is an excerpt: 
‘Moonraker have worked with Whistler to customise a UK band plan for the scanners! This ensures the radios cover UK bands in the correct steps and the correct mode. When a user performs a service scan, this will search in the correct steps for the selected band ensuring maximum received stations. The radios will receive both amateur and commercial DMR transmissions, because – apart from the frequency – they are fundamentally the same mode. The radio is supplied with software, and users can select mode when writing memories or select auto, and the receiver will work out the mode itself.

This multi-system adaptive digital trunking scanner supports Motorola P25 Phase I, X2-TDMA, Phase II and DMR, making it capable of monitoring the following unencrypted channels/systems:
-    Conventional DMR (Entered as a DMR trunked system)
-    Hytera XPT 
-    MotoTRBO™ Capacity Plus 
-    MotoTRBO™ Connect Plus 
-    MotoTRBO™ Linked Cap Plus systems

Key Features and Specifications: 
-    Frequency: 25-54MHz, 108-136.99MHz, 137-174MHz, 216-379.97MHz, 380-512MHz, 764-781MHz, 791-796MHz, 806-960MHz (excluding cellular), 1240-1300MHz
-    Simple Zip Code programming 
-    Preloaded UK MicroSD card included. 
-    Easy updating via the Internet 
-    APCO P25 Digital Phase I & II
-    The removable magnetic head can be operated remotely 
-    Scanning at up to 70 channels/second 
-    CTCSS and DCS sub-audible decoder
-    Dedicated SKYWARN®/Weather button 
-    IF Discriminator Out 
-    User upgradable CPU firmware 
-    Spectrum Sweeper 
-    Tuning Steps: 2.5, 3.125, 5, 6.25, 7.5, 8.33, 10, 12.5, and 25kHz. 
-    Clock / Calendar 
-    Store Favorites Scan List


Unpacking the scanner, I found the unit quite small but nicely made. It comes with a ‘wall-wart’ style PSU, and a telescopic antenna with a BNC connector. The control head of the TRX-2 is detachable, and the unit comes with a cable to allow the control head to be sited up to 2m from the main body of the scanner.

Without any more ado, I connected the PSU, attached the antenna in the back and switched on.

With the Moonraker code plug installed on the TRX-2, the scanner has been configured with all the possible frequencies for Airband (both Civil and Military), Marine, DMR Simplex, DMR Repeater, NXDN Repeater, P25 Repeater, FM Simplex, FM Repeater, DMR446, and PMR 446.

This means that you can just switch on, and the unit will start to scan these frequencies. It’s as simple as that, and that’s exactly what will happen.

However, switching the unit on is a reasonably extended process, because the radio has to load all the frequencies stored on the removable SD-Card in the scanner into the memory of the unit.

Because of the sheer number of frequencies, this can take up to 5 minutes. 

Having waited for the configuration to load and scanning to commence, I very quickly started to hear lots of activity on the Airband, mostly civil, but quite soon, the scanner stopped on a military airband frequency, which I had not heard before, despite being quite local to me. That was very interesting and showed the beauty of having all the frequencies programmed into the scanner.

Having done a quick test using the supplied telescopic antenna, I found a SO-239-to-BNC adapter and plugged in my rooftop dual band 2m/70cm ‘white stick’ antenna, which does a good job of receiving my many frequencies of interest. I made the mistake of switching off the TRX-2 whilst I did this, but wished I hadn’t, because having done so, it took another 5 minutes or so to reinitialize and load all the frequencies again!

I found that predominantly, I was hearing only stations on the airband. This is because, I think, the Airband banks of frequencies are significantly bigger than the other banks, so the scanner spends more time going through these. Therefore, a quick transmission on the Marine Band, say, or a quick call on an amateur repeater, either FM or DMR, could easily be missed.

I soon learned that, if I wanted to listen, in particular, for Marine Band traffic, it was best to go into the menu and temporarily disable the Airband scan list, so that the scanner could spend proportionally more time scanning the Marine band.

I discussed this with Technical Support at Whistler, and they told me that the scanner scans at a rate of around 80 channels per second. With around 1650 channels to scan, the scanner is going to take around 20 seconds to go round all of the memories. Airband represents around 15 seconds worth (1271 objects) of that total, so if you are looking for traffic in other bands, it will probably be worth narrowing down the scan lists a bit, or at least temporarily disabling the Airband. 

This approach worked well, and I found that, despite living miles inland and at least an hour’s drive from the coast, I heard some transmissions on the Marine Band that I had not heard before – some traffic on the River Thames approaching a nearby lock, for example, as well as a sailing club setting up a course on a lake. Both of these transmissions occurred on channels that I wouldn’t have thought of scanning, so I was delighted.

It was also apparent by now that the unit was capable of decoding DMR transmissions. I was hearing at least three amateur DMR repeaters, one on the 2m amateur band and two others on the 70cm amateur band.

I was pleased to see this and to note that the TRX-2, as supplied by Moonraker, did not require any further purchases to activate DMR (or indeed NXDN) mode; something which is necessary with some other scanners.

When in DMR mode, the TRX-2 shows the Talkgroup, Color Code and RadioID of the station transmitting.

Content continues after advertisements

I found the receiver to be sensitive. Some scanners I’ve used haven’t been great around 430-460MHz. This can be quite an interesting area – there’s the amateur 430MHz band, PMR446, as well as the commercial activity between 450 and 460MHz or so. The Whistler was good in this band; on a decent antenna, I felt it performed very similarly to some of the dedicated amateur bands receivers I have here.

Although the TRX-2 is capable of receiving NXDN and P25 transmissions, I was not able to try this out in rural Oxfordshire.

Something I particularly liked was the TRX-2’s capability to record. For example, you can do a search for new frequencies and record the audio, along with frequency information. A friend of mine who has a TRX-2 uses the recording feature to save the traffic on a particular trunked DMR system to listen to at a later date.

In the configuration for each channel, you can decide whether or not you want to record traffic. The recorded audio files are stored onto the SD card.

Programming the TRX-2
Although the configuration of the TRX-2, as supplied by Moonraker, is really excellent, if you are anything like me, you may want to make some changes! For example, you might want to add a scan list, which contains local Shopwatch or other frequencies. I wanted to add a 10m scan list with 29.600MHz FM and some other 10m repeater outputs too. 

When I first installed the Whistler EZ-Scan software on the PC – which included the driver for the scanner – all seemed to be well, but I could not read the frequencies from the scanner. I fiddled around with no luck and then contacted Chris Taylor at Moonraker who kindly put me in touch with Technical Support at Whistler.

It became apparent that the SD card in the scanner had a minor corruption, so I was able to resolve that and reinstall a particular folder. Once that was done, I was able to read and write frequencies to and from the scanner and inspect the setup of the scan lists already installed.

Having got the hang of all of this, I decided to make a Military Airband scan list and move all the military frequencies from the Airband scan list to the new one. To do this, simply highlight all the military frequencies and amend the scan list number. It takes a while, but it will update them all. This meant that I could be more granular in my searches – and it had the benefit of reducing the size of the largest scan list!

I found it was much quicker to write the changes to the scanner by removing the SD card from the TRX-2 and placing it in a card reader in the PC, rather than using the USB connection. You’ll need to use the USB connection though if you upgrade the TRX-2 firmware (scanner firmware or DSP update)

Remote Control
Whistler also provides a remote control program, which can be downloaded from their website. The firm states that it is a ‘demonstration’, rather than a finished program. I really enjoyed it though.

To use it, you’ll need to set up the USB connection from your PC to the scanner. On your PC, you’ll need to look in Device Manager/Ports to check the number of the COM port for your scanner. If you’ve got several ports showing, just unplug the USB lead to the scanner and plug it in again – you’ll see which of the ports vanishes and then reappears. Select the port in the remote control program and then hit Begin Session.

You should then start to see data from the scanner echoed in the remote control program. You can operate the scanner from the program, but actually what I liked about it most of all was the fact that the frequencies that the scanner stops on are shown in a list in the program. As I’m often left wondering what the last frequency I heard was, having not hit ‘stop’ quick enough, this is a very useful reference.

I did find that, if the scanner was particularly busy, then not all frequencies were logged. My guess is that the program might work better on a faster computer than mine (the shack PC is a few years old now), as the program probably hadn’t had time to finish processing of the one data packet before another one came along. As well as showing the log on the screen, you can log to a file on your computer for future reference. 

Overall impressions
I really enjoyed the TRX-2. I found it easy to use, once I had got through the ‘familiarisation’ stage. I also found it to be sensitive on all the bands where I was able to try it, and I particularly liked the fact that DMR came as standard and did not require spending more money on an upgrade.

There were some features that here in the UK you can’t use – for instance, the location database, which is for North America only. However, the pre-programming of the Air, Marine, Amateur and some other frequencies into the ‘code plug’ means that you can use the TRX-2 out of the box and hear plenty of interest straight away – which is a big advantage.

Retailers have said to me that often people buy scanners but are disappointed when they get them home, as they are not sure what frequencies to listen to. The scan lists provided with the TRX-2 get around this problem perfectly.

I found programming from the PC easy (but do pop the SD card out of the scanner and into your PC to save time) and I found value in the Remote Control program, particularly for logging.

The capability to record onto the SD card will also prove useful and interesting to many. 

Many thanks to Chris Taylor of Moonraker and Mike Batten of Whistler for their assistance in providing this review.


Content continues after advertisement