2 Nice "catches" on Stockholm Radio

 

Heard the pilot of this aircraft calling Stockholm Radio on 11345khz this morning (0957UTC) from Paris Le Bourget for a selcal check. He spoke to the Stockholm controller partly in Swedish.

The aircraft is an Airbus A318 Corporate Jet (Elite) operated for Hamza Al-Kholi (hence the HK on the tail), a Saudi Businessman. I read recently on the Civil Aviation forum that these pre-flight calls on HF must take place after re-fuelling for safety purposes, which I found interesting.

The second interesting flight was a Smartwings Beoing 737-800 OK-TSF calling for 2 radio checks on his way from Prague to Bacau, Romania

Listening mostly to VHF, where I get my fair share of Ryanair and British Airways, it is really cool to hear such an unusual range of aircraft and companies on Stockholm Radio.

Ethiopian Freighter on 11300 khz

 

After reminiscing about former HF activity on 11300 on the Civilian Aviation forum, I decided I'd listen in for a while last night and I caught a huge signal from this Ethiopian Airlines Cargo 737-800 as it entered Khartoum airspace on its way to Addis Ababa from Benin. All this on a little Tecsun PL660 with it's telescopic whip in the kitchen!

Interesting HF Logs February/March 2021

 After an interesting message exchange with IrishSea about HF listening, I am posting a few of my top logs over the past few weeks.

Bear in mind that due to horrendous local QRM I'm only listening on a portable (Tecsun PL660) with it's built-in whip, or homemade broadband active loop from here in Dawlish, SW England:

18FEB21 0932 8891khz Bodo Radio working United flight to QSY Iceland 8891 at 78N 00E
20FEB21 0730 8888khz Syktyvkar Weather in Russian
02MAR21 1647 8888khz Samara Weather Russian heard word "Kazan"
11MAR21 1841 11300khz Seychelles ACC wkg Reunion 9971 from St Denis to Paris
11MAR21 1842 11300khz Khartoum ACC wkg Turkish 6152 from Entebbe to Istanbul

Thanks. 73 Adam

Logs June 2020

4182.0   23JUN20 2225 USB RMCW West, Naro Fominsk channel marker "T"
5292.0   23JUN20 1940 USB RMCW West, St Petersburg "Fazan 37" channel marker "D"
8123.0   23JUN20 0950 USB french fishermen "peche" "pecheurs" catch weights etc
6824.0   22JUN20 0732 CW 5 figure groups // no ID
9996.0   21JUN20 0839 CW Moscow Time Signal ID "RWM" slow morse . good signal
8191.0   20JUN20 2025 CW Russian Navy Kaliningrad RMP msg to Russian Baltic Fleet REO
  321.0   18JUN20 0918 CW St Mary's Isles of Scilly NDB beacon "STM"
10871.0 16JUN20 1906 CW Single Letter Beacon Moscow "C"
  345.0   14JUN20 0745 CW Villacoublay AFB near Paris NDB beacon "TA"

 
RMCW: Russian Military Commandment Network

Homemade Active Loop for LW, NDBs, MW and HF

I've been experimenting with loop aerials for years as from my very first project I was wowed by their ability to reject local noise and give me back my hobby of short wave listening, which was becoming increasingly difficult as RF noise plagued the ether.

My first loops were ugly and crude but worked extremely well and saved me lots of money. Over the years the designs have improved and looked more like something I was proud to have in the shack.

But being interesting in a huge chunk of radio spectrum, from LW right up to HF, I needed to swap loops around. A lot. And even assuming I could have made a passive tuned loop to cover all of this, I would still have needed to retune each time I changed frequency.

In the end I suppose I compromised and ended up with a wide 2.1 to 18MHz loop for HF (well, most of it) and pretty much neglected LW, MW, and NDB DXing.

So it had long been an ambition of mine to build my own active loop. The Wellbrook loops were too big and too expensive for me, and with the little outside space I have available being plagued by RF, would need to be sat inside the shack, and to be honest I found their design too ugly for this!

The AOR active loops were my favourite, but still they were very costly and I was put off by the very small 30cm diameter. I know from my own experiments that doubling up to, say 60 or 70cm, gave a huge in signal, especially on the 5 and 6 MHz bands, were I do a lot of utility DXing.

So I decided to build my own. And it has been surprisingly straight-forward.

I bought the amplifier ready assembled from Rainville Communications in California. Luke there was incredibly helpful, and after patiently explaining to me what I needed for the project (I was getting confused between an active loop and adding a PRE-AMP to my tuned loops, that would have added more noise and little else) I ordered the LAMP-1A HF Receiving Loop AMP.

Putting it all together was really simple, though you do need to have basic soldering skills just slightly beyond what you might need to build a passive tuned loop, but only ever so slightly. If I can do it, anyone can! I had given months of thought to how I wanted it to look, as this was very important in this build. I wanted a small, somewhat flatter box than my normal bulky looking ones, and a sleeker, lower-profile design. I wanted a little LED to show me when it was on, and ideally to give an indication of the amount of gain I had selected. The variable gain is simply a variable resistor (potentiometer) used to reduce the power (I chose a 1K linear which is about perfect). I used a 75cm Witzig Hula Hoop from onbuy.com and 15mm single hinge clips from Talon to secure the loop to the project box.

So for £50 I ended up with what I think is a very sleek-looking loop which outperforms anything I have ever made before. The AMP is superbly quiet and generates no noise at all, unlike previous supposed "low noise" RF Amps I have bought before from China for £6.

Rainville state it is an HF AMP, but it works extremely well all the way down to 200khz, which was a really nice surprise when I was testing it out. I spent a long time comparing it to a larger passive tuned loop, and in every respect it outperformed it. I was really surprised as I had a pre-conceived notion that any kind of amplifier in a noisy RF environment was a big no-no.

The joy of being able to hope around from NDBs in the 400khz band to HF, back to MW, and all without re-tuning or swapping loops is indescribable. SWLing heaven!

I am attaching some photos of the loop. I have also done Youtube video

Message me via comments on this blog or my Youtube Channel if you want to ask me any questions. I enjoy hearing from you and chatting about this fine radio hobby of ours.

73 Adam

Realistic DX394 RAM Memory Back Up Battery Replacement

 

The DX394 has a small rechargeable battery soldered onto a totally inaccessible place in the front of the radio, and when the battery failed on my radio, I was faced with a row of irritating flashing zeros on the clock, a display that reverted to 150khz, and blank memories, each time I returned from a holiday or weekend away and the power to the shack had been shut down. Eventually I put the radio in my cupboard and stopped using it. Then I discovered someone called Dino from the DX394 io group had discovered a possible way of bypassing the very complicated disassembly of the front panel (which requires manufacturing your own tool to remove the tuning knob). It is shown above in my slightly edited photo to aid clarification to complete beginners like myself. 

I was a bit reluctant to take my soldering iron (and craft knife for severing the PCB trace) to my beloved radio, but it didn't look like rocket science and I figured I'd give it a try. 

I have already done a couple of radio mods, easy ones. Like the Uniden 9000XLT discriminator tap and the PRO2005 EL backlight replacement. I'm a rubbish solderer, I have shaky hands, but I'm careful and methodical and down-to-earth about the idea that if I damage the radios beyond repair they are not so expensive they can't be replaced one day. I| might even use the opportunity of their demise to try a different radio. So with this mentality you can't go wrong. 

I am so glad I tried all of these mods and would not hesitate to try them again if the need arose. They are not too hard and really help boost your confidence. 

Firstyl, you have to buy a Panasonic VL2020 battery from ebay (about £8).

When you have removed the top panel of the DX394 if you look inside at the back of the front panel you will easily find D206 in the diagram.

To sever the trace to its left where shown you need a sharp knife. I practiced a bit on an old, broken radio, to figure out the pressure needed to break the copper. It did need pressure, a steady hand, and using your other hand as a brake in case you slip. But afrer a few firm scroes across the trace and lots of inspections with a jewellers loupe (an ordinary magnifying glass was useless) it was clear when the copper had been cut completely. A useful tip: after each scoring across the trace, I wiped the debris with a small cotton bud dipped in surgical spirit to more easily see the result of the cut.

Soldering a small piece of insulated wire from pin 1 of D206 I firstly tinned the tip of the wire and dipped it in flux before carefully soldering it in place. That would be soldered to the positive terminal of the battery. I did the same thing with the negative lead, soldering it to the big blob of solder shown on the diagram.

The result:

I then put the battery inside a small memory card folder and neatened thing up a bit.

Although the battery read 3V when I inserted it, after just half an hour it had gone down to 2.8V and after a 30min power down, the memories were empty again. So I left the DX394 connected to a 13.8V power supply overnight for two consecutive night, to fully charge the new battery and since then everything is working splendidly.

I can't tell you what a joy it is to have the memory working again. The radio has been reborn. To switch on in the morning and see the right time, no flashing, and my last used frequency, with all the memories intact is indescribable joy! I must be a true radio geek!

Had it not worked, I would have bought another DX394 cheaply and tried again, as I have always loved this radio. The MW and maritime MF bands are incredibly sensitive. HF sensitivity is excellent. The memories are quick and easy to use and program and change and delete. The display is large and pleasing to look at.
Sadly AM broadcast listening is fatiguing. Most people agree here. But I use a DX400 for broadcast stuff nowadays, and with its excellent murata filters and audio quality use the 394 for aero/utility monitoring, MW and maritime MF.

I'm a big aero fan, and always monitor Stockholm radio and Shanwick. The DX394 is perfect for this.

Anyway, message me if you need an advice via the comments or QRZ (M6RDP). I just wanted to show you this excellent mod here on my blog.

Bye. 73

Kenya Airways Ops LDOC Frequency 13330khz Nairobi

I was beginning to think that the only aircraft ops I could hear these days on short wave was via Stockholm Radio (oh and my latest exciting catch of Saudi Airways on 8968khz)

But on the latest arrival in my shack, the XHDATA D808 from Australia, I was tuning around its extremely user-friendly memories when I came across some South African sounding voices on 13330khz. Turned out to be Kenya Airways Ops control in Nairobi selcalling KQ250 en-route to Seychelles and KQ 211 inbound from Mumbai with METARS/weather reports.

So this was on 17th June 2019 at 1755UTC on the XHDATA D808 indoors on its telescopic whip.

The XHDATA is simply superb for a quick check on each memory channel and then a quick tune up and down a few khz of each channel and all without the need to switch between VFO and memory mode which is what I have to do on the Tecsun PL660.

I am going to do a review on this latest radio to come out of China later on, but I have had my eye on it for about a year, since reading about its very well implemented VHF airband, and FM RDS which are both features I knew I would use a lot.

I've also had some great catches the last few evenings on 8879khz with Mumbai radio working lots of aircraft travelling from the Gulf to India. Qatari Airways, Express India, Singapore Airlines..... it's been superb.