Radtel RT 950 Pro as an Airband Receiver?

 So, after a very long time of not posting here I thought I would take the opportunity to 'resurrect' this blog and post on my findings with my recently purchased Radtel 950 Pro radio. Just like Chinese manufactured cars, the UK is being 'flooded' with Chinese radio equipment so just how good is the 950 pro particularly for airband listeners?

I have to say, I am comparing the Radtel 950 Pro against my Icom IC R15 which is a completely unfair comparison as the Radtel cost just £89 and the Icom over £400! The R15 in my humble opinion, is one of the best radios around for Civil and military airband listening right now and I think, ranks alongside 'benchmark' receivers such as the Signal R535 & Yupiteru MVT7100 (I've owned both in the past) but I'm not going to go into all the reasons why just now.

I bought the Radtel for two reasons, number one, I wanted a tougher more rugged (and cheaper) radio that I could use when 'in the field' away from home or at an airfield/airshow which is not very often for me. Reason number two was because I just occasionally listen to HF aero frequencies which the Radtel is also capable of doing but I am not able to compare it alongside a 'better' HF radio.

So having compared the Radtel alongside the R15 on the very same dipole antenna, I can honestly say on VHF airband the Radtel is really very good on both audio quality and sensitivity, I was truly surprised by it's performance! although some of the weakest signals come through as carrier wave only with no discernible audio whereas those signals are still good audio on the R15 as you would expect.

It is a slightly different story on UHF military band however. It is quite difficult to compare signals on UHF mil as transmissions are often very short, but I have managed to do so, by comparing known frequencies primarily for Swanwick military. So having monitored 233.725MHz on both radios, reception seems very good on the Radtel but by the time you reach Swanwick mil central on 252.875 the Radtel is almost completely deaf to very strong transmissions here. I was able to compare signals on 256.200 (a known Lakenheath air to air) and then further up the band, Swanwick mil on 275.500 and I have to say the Radtel remains pretty deaf on those frequencies! 

Just quite how low and how high this 'null zone' extends I'm still working on, but what I have noticed is that known frequencies that are 350MHz and above, are coming through load and clear again and comparable to the R15.  

I think all in all, given it's price point, you are getting a lot of radio for your money and it will serve the purpose for which I brought it. It's never going to replace my R15, but it has some great features such as displaying three frequencies at once etc. 

Just a point on it's memory features, what I consider memory 'banks' are labelled 'zones' on the Radtel. The free software available for programming memories is not great, but it works. In my very unscientific testing, it seems to scan memory channels at a very slow 5-6 channels a second (100+ on the R15!) so for airband monitoring you really don't want to be scanning more than a handful of frequencies at a time. 

In conclusion, if your main interest is VHF air you could do a lot worse than the 950 pro, it's audio quality and sensitivity really surprised me, however if you monitor a lot of mil air frequencies like myself, the 'null reception zone' around 250-275MHz coupled with the very slow scan rate of memory channels means it's not so great a choice. As I've already said, it's never going to replace my R15 as my main listening device but I do still believe, you are getting a lot of radio for less than £100!

Uniden UBC125XLT my scanner of choice at the moment!

Well, its been quite some time since I posted here! I must admit, I mainly tweet in real time these days regarding military aircraft movements and frequencies being used etc. However, I do want to keep this blog "alive" as there is a lot of information that is still useful and relevant going back some years for anyone quite new to the hobby of airband listening.

After having sold a Uniden 125XLT last year in preference for a Uniden BCT15X I find myself back with a 125XLT! Incidentally I also purchased a Yaesu VR120D to take on holiday with me to Devon last summer and it was an awful radio! VERY susceptible to interference and as a result, pretty deaf compared to the Unidens I'm used to and so I wouldn't recommend one of these to anyone and it was moved on to a new home pretty quickly!

The BCT15X is a great scanner (albeit in terms of sensitivity identical to the 125XLT) but with it's "dynamic memory" it was just too complicated for me as my only interest is airband.

And so, I find myself back with a 125XLT which provides great reception with very little interference or breakthrough in my location, using my DIY loft antenna which gives me excellent results.

I actually love the idea of fixed memory banks and channels numbers because I can still group things logically and memorize my most frequently used channels which means I just punch in the channel number followed by the "hold" button and I'm where I want to be very quickly! 

This coupled with its excellent features such as temporary lockout (resets when powering radio on & off again) and the priority features such as being able to designate one channel out of each bank as a priority and then using one of the priority functions such as "priority DND" (do not disturb: so it will only switch to a priority transmission IF there is no signal on the frequency you're monitoring at the time) means you have something resembling a "dual watch" feature, in fact, it means you can be monitoring up to 11 frequencies virtually simultaneously! (the one your on plus 10 priority channels).

That's it for now and if you're interested in following my real time military movements tweet then give me a follow: @Su39frogfoot

ICOM IC-R5

I have now received my little Icom IC-R5 back from Geoff at Castle Electronics in full working order who I can highly recommend for repairs.

This is going to be an ideal receiver for when I'm 'on site' at airfields and airshows, it's so compact but seems very sturdy and robust. I have to say after some initial testing, the supplied rubber duck antenna is next to useless, but as soon as you replace this with just about anything else, it really begins to shine and is a very capable and sensitive receiver on the VHF & UHF airband at least.

Many people have complained about the lack of buttons on the little Icom's making them difficult to use, but after having read the manual several times over on programming frequencies into memories and then into banks and also programming search bands (or scan edges as Icom like to call it) I am now able to do everything I want to do without referring to the manual. It's really quite quick and easy to tune frequencies I want to get to manually in VFO mode too.

I have been messing about with the Icom connected to my loft antenna usually reserved for my Uniden BCT15X and I had quite a shock this Sunday morning! While tuning around on the Icom I could clearly hear a constant broadcast from RAF Wittering coming through the squelch and showing one bar of signal on 123.925.

The broadcast was as follows: 'Wittering radar is now closed and will reopen at 0730 Zulu on the 14th August'.

I was quite surprised I could hear anything from Wittering given my location on the West side of Leicester but what was more surprising was when I reconnected my antenna to the BCT15X, the transmission wasn't coming through the squelch and even when I backed it off, the broadcast was barely audible! Could the IC-R5 really beat my BCT15X in pulling in weak signals? Well, yes it does in this case!

So, all in all, a very capable little receiver for airband at least, HOWEVER, the scan speed of memory channels is woefully inadequate in my opinion if you intend to scan a lot of frequencies, because while it will search at about 30 steps a second, it's actual scan speed of stored memories is just 10 CHANNELS A SECOND.

Now, if your going to use this radio 'on site' as I will be doing, this is not much of an issue, because I will typically be monitoring a handful of frequencies at the most, but for use as a home based scanner monitoring perhaps hundreds of frequencies as I do, it is simply not up to the job. To be fair to Icom, it does say on the front 'communications receiver' and not 'communications scanner' !

Having said that, I hear the slow scan speed has been addressed with the Icom IC-R6 so maybe getting hold of one of these will be my next goal....

Icom IC-R5 and Scampton Air Show

Well, I decided to purchase a 'spares or repair' Icom IC-R5 recently with the hope that it could be fixed primarily for me to use 'on site' at the Scampton Air Show which is the only event I'm likely to attend this year.

Having seen a recommendation for Castle Electronics (hamradiosales.co.uk) after a short conversation with Geoff there, I despatched the IC-R5 off to him last week hoping he can get it working. As yet, I've heard nothing, so watch this space!

I have owned an IC-R2 and R5 in years past, and the Icom IC-R5 is a one bank or all banks scanner. It's scan speed is not very fast either, but usually when 'on site' at an air show, I'll be monitoring a handful of frequencies at the very most, so it's drawbacks are not much of an issue for me in that situation.

I thought the little Icom would be an ideal 'discrete' scanner to use when out and about which is not very often for me, hence why I didn't want to spend much on it. If it can indeed be fixed, I'll report back on it's performance when used 'on site' and when attached to my home antenna.

As I mentioned, Scampton is about the only air show I'll attend this year and I know there's quite a bit of skepticism of the price versus content for this show at the moment on various forums.

I would like to give the organisers of what is a brand new event the benefit of the doubt but I must admit the 'flying' content with just over a month to go looks fairly light considering it will be nearly £80 for myself and my wife to attend (better value admittedly for families as under 16's go free).

There has been much fanfare in recent emails of attendees to the show, only to learn they are joining the static display only, which is great, but at the end of the day if I want to look at aircraft sitting stationary, there is a large number of air museums I can visit at any time to admire aircraft in that way. Is it only me or do most people want to attend an air show to see aircraft in their natural environment and that means flying!

Well, I'm holding off buying tickets for now as I want to see if anything else develops in the last month or so. I may well attend my local show down the road - The Victory Show at Cosby on the same weekend - not a full scale air show by any means, but they always puts on a good flying display and for £15 advance ticket cost is excellent value!  

As with all air shows, it's good to include the air show 'common' frequencies in your scan: 121.175 - 130.675 - 132.9 - 130.5 - 130.625 - 134.55.

Cosby Victory Show have always tended to be allocated 121.175

Uniden BCT15X

I've had my Uniden BCT15X for over a month now and I am thoroughly pleased and impressed with its features!

As it was supplied with a serial cable which is next to useless for most modern computers, I have programmed it manually which was actually quicker and easier than I thought it would be. Although it was probably two to three hours work in all to create a total of three systems (CIVIL AIR, MILITARY AIR & TACTICAL AIR) each containing various groups and then programming individual channels with alpha tags under all the group's, I now have everything set out just as I want it and it's very easy to instantly enable or disable groups and/or systems as I'm scanning (which incidentally it does very fast).

I've had a mess around with some of the features such as the bandscope function which allows you to set a centre frequency, then set the band width and step for the frequency search and will then display a signal bar for any transmissions found in the search range you have set. In fact, messing around with this feature enabled me to find an E3 AWACS frequency that was in use at the time!

Putting it alongside my UBC125XLT I think it is a little more sensitive but of course, any radio is only as good as the antenna used and it's position.

Above you can see my BCT15X in bandscope mode with 126.000MHz as the centre frequency with a total bandwidth of 1 MHz (from 125.5 to 126.5). The largest signal bar to the right of centre is East Midlands approach transmissions being intercepted on 126.175.

If you have a BCT15X and are struggling to get to grips with using it please check out the easier to read online manual on the Marksscanners website. 

Airband Scanners and the Need For Speed!

This is something I've touched on with a recent post when comparing the Uniden UBC125XLT with the Yupiteru VT225 and that is the speed with which a scanner will scan its memory channels (search speed is also important when looking for new frequencies too).

Many scanners available today offer scan speeds in the region of 20-40 channels a second which may sound quite reasonable. I think some of the AOR, Icom and Alinco radios scan at these sort of speeds and I believe the older Yupiteru scanners are in the region of 30 cps (channels per second) and many of the radio Shack/Realistic radios such as the PRO 2042 are in the region of 40 cps.

As I say that may sound reasonable, but when you have perhaps say 500 memory channels stored (quite reasonable even for airband especially if your interest is military and civil) it would take a scanner doing 20 cps 25 SECONDS to get round to checking each channel again! and when you consider that transmissions are often very short particularly on military airband you can begin to see that it would be possible to completely miss a transmission without ever being aware of it and then you're left scratching your head trying to lock on to that aircraft and the frequency it's using, so SPEED REALLY IS IMPORTANT in what determines a good radio scanner for locking on to those signals!

This is one area the Uniden radios in particular seem to excel, the 125XLT I have at the moment for instance has a published scan speed of 80 cps and I can honestly say, I've never picked up as many transmissions as I now do on this radio.If it's within reception range, I'll hear it.

My next intended purchase is a dedicated home based scanner and I'll probably be looking at the Uniden BCT15X as this has a stated search and scan speed of 100cps! I appreciate this scanner is not for the faint hearted as it has 'dynamic memory allocation' which I'm not going to explain here but it's quite a steep learning curve compared with most scanners today but I'm pretty familiar with the Uniden radios now having previously owned a 3500XLT with dynamic memory allocation so I think I know what I'll be doing with it so watch this space. Once I manage to get hold of one, I'll post my opinions and experience with it on here!

Air Traffic Control and Bandboxing

Many of you are perhaps familiar with 'bandboxing' in air traffic control circles, for those that are not familiar with the term it basically means a controller is working more than one sector and/or frequency at a time.

Remember these? An early digital airband radio from Swinburne

For instance, the Daventry high sector for mainly northbound traffic over the east midlands uses 127.1 and the Daventry high sector for mainly southbound traffic over the west midlands uses 129.2. Now this morning (Sunday morning) traffic levels are lower and therefore one controller is working both sides of this sector and hence both aircraft and controller can be heard on both frequencies (transmissions re-transmitted on both frequencies). You may hear the controller on one frequency and the aircraft on another frequency.

This situation frequently occurs for me with Swanwick military central because I can always hear the controller on 252.875 UHF but if an aircraft is talking to him on his VHF frequency (128.7) I usually only hear the aircraft side of the conversation (probably different transmitter sites in use). 

Again, it can be down to a lot of factors such as your location and the location of any actual transmitter sites that 'repeat' the transmission from Swanwick etc.

But hopefully, that gives you an idea, I'm no radio 'tecchy' so would not even try to explain the more technical aspects of this!

USAF Reach flights

On a clear day I often see 'reach' flights crossing the UK, usually on a well used route either travelling east or west through southern Wales (sometimes further south using reporting point 'gitus' approx 15 miles north of Lands End) across to RAF Marham in Norfolk (and then on to 'navpi' in the north sea east of Great Yarmouth).

Aircraft using these callsigns typically include C130 Hercules, C5 Galaxy, C17 Globemaster and KC10 and KC135 Tanker aircraft and occasionally other types.

These flights usually cross 10-15 miles south of my location but are clearly visible from here in Leicester on a clear day. Occasionally their routing is slightly different such as 'reach 707' (C130J) early this morning that went straight across eastbound from central Wales (usually but not always heading to Ramstein) and passed almost overhead my location.

These flights are almost always working Swanwick military on 252.875 and usually a few miles east of here get transferred to Swanwick Military 'East' on either 259.6 UHF or 133.325 VHF.

Another common route for 'reach' flights is from the Northwest (Lake District or further North) across Yorkshire, Lincolnshire and then across the North Sea off the North Norfolk coast and from the Yorkshire area these usually work Swanwick civil control on 126.780 until passed to Maastricht when Eastbound.

I'd be interested in knowing the frequencies they usually work further North if anyone can help?

Uniden UBC125XLT and the battery save feature

I've mentioned before that the only slight annoyance with my Uniden UBC125XLT is the battery save feature which automatically kicks in after a couple of minutes when I am monitoring a single frequency and frequently means I miss the first second or so of a transmission which can be vital if the pilot is reading back a frequency change for example.

This feature is only apparent when connected to my small extension speaker as it generates a 'thump thump' noise as the circuitry is continually switching on and off!

The only 'workaround' I have found so far is to have one of the priority modes activated while monitoring a single frequency. My preferred option is the Priority DND option which checks any priority channels that are activated every 2 seconds as long as there is no transmission on the main frequency being monitored. With priority activated the battery save function does not 'kick in' at all.

Of course, you might say you don't want to be monitoring anything else, well if that's the case, if the frequency is in a memory channel, say for arguments sake, in bank 1 then make that channel the one and only priority channel allowed in that bank and only activate bank 1 for scanning, then put the scanner in hold mode on the frequency you want to monitor along with the priority mode and the scanner will be only listening to that channel and the battery save feature will not activate at any time!

The other option is the same as above ie. activate only the bank your channel is stored in during scan mode, hold on your desired channel, make that the priority channel and then activate 'Priority Plus' which will only scan priority channels in activated banks, so in this case, it will only monitor the one frequency in the one and only active memory bank.

Anyway it's not ideal, but it does work if you find the battery save feature an annoyance like me.

Yupiteru VT225 vs Uniden UBC125XLT

So, I've had an interesting few days with my Yupiteru VT225!

As soon as I got the VT225 'out of the box' I had forgotten how relatively small the LCD display is. I guess I've become very used to the nice big, bright display on my 125XLT!

After a relatively short period of time putting these radios side by side connected to my attic DIY dipole antenna (which incidentally, still performs better than any commercial product I've tried) what has become evident is that the VT225 was not pulling in any signals any better or stronger than my 125XLT! this was bit of a surprise, I really expected it to do better somehow.

With the radio connected to the attic antenna, it was pulling in all sorts of 'hash' and in fact, when trying to monitor Lakenheath approach which I regularly listen to on 309.200MHz, there was 3 signal bars of 'white noise' making it impractical to monitor. I also noticed on other frequencies where the background noise could easily be 'squelched out' I was getting the muffled breakthrough of strong local airways transmissions in places, something that I simply do not experience with the 125XLT. Don't get me wrong, the 125 is not perfect, there are a few odd frequencies that are susceptible to strong data transmission breakthrough in my location, but they are VERY FEW AND FAR BETWEEN. 

It's not all bad, I think the Yupiteru VT225 is a sensitive radio, but it is probably best used with a telescopic antenna attached directly to the radio itself and in the right position, is a very good receiver. Worth noting is that the audio quality on the VT225 is excellent and it has a very 'bass' quality sound to it. To get a similar quality of audio I have to attach a small usb charged speaker to the 125XLT. 

Interestingly, the scan rate quoted for the VT225 is 30 channels a second as opposed to 80 channels a second quoted for the 125XLT. When it comes to scanning airband and not wanting to miss the often, very short transmissions (particularly military) in my experience, SPEED IS EVERYTHING especially if you have several hundred frequencies stored in memory. 

All in all, I'm glad I took a trip down 'nostalgia lane' and it's made me appreciate what I have in the 125XLT - it is an excellent scanner for airband (and for the money) and the host of features and it's ability to reject unwanted signals have come along way since the Yupiteru scanner era of the 1990's. Do I sound like I'm on Unidens payroll? wish I was!

So what now for the Yupi? well it's already moved on to a new home! And my Uniden UBC125XLT is staying right here with me! 

What can I try next? fancy one of this little Icoms....