Even the DNO get it wrong sometimes.

Medium wave (MW) listening - that takes me back to the days of 'Short Wave Magazine' and listening to distant broadcast stations late into the evening!

As you are probably aware, stations are fast disappearing from the MW broadcast band in the UK, as a complete shut-down is planned by 2027. 

Tuning across the MW broadcast band here just now, the only stations to be heard were:

• BBC Radio 5 Live (693 kHz // 909 kHz)
• BBC Radio Scotland (810 kHz)
• Talksport (1053 kHz // 1089 kHz)
• Manx Radio (1368 kHz)

Also heard were two unidentified stations on 756 kHz and 1296 kHz, both very weak.

- Ross

Ross C said:

listening to distant broadcast stations late into the evening!

e.g Radio Caroline. :-)

I was thinking only a couple of days ago (why?) of a 2-transistor radio (wireless receiving set). It is all streamed nowadays, save perhaps for the World Service, which reaches even where the local authorities would rather it did not.

DNO  really look for noise or are they detecting something else like heat or vibration??

Some years ago we had niggling fault with the supply at work ... the DNO had several attempts to locate the fault as it gradually got worse and in the end they resorted to repeatedly replacing the substation fuse while their colleagues simply walked around listening for where the bang was loudest - and that's where they dug. Crude, but seemed effective! At a similar time we'd started using TDRs to locate faults on data network cables, so fancier technology certainly existed, but the DNO didn't seem to use them.

In your case it might just be they kept digging up likely joints until downstream customer stopped complaining of flickering lights etc...

   - Andy.

Not quite as far back as Radio Caroline!

I'm only going back as far as the 1990s here, when I could also be found doing such esoteric things as listening for distant marine and aeronautical non-directional beacons (NDB) just below the MW broadcast band! 

Similar to MW broadcasting, NDBs are now obsolescent. All the marine NDBs around the UK and Ireland were shut down by the early 2000s and whilst aeronautical NDBs are still in use, they are much reduced in number.

I should really go now, before I start reminiscing about hyperbolic navigation systems at 100 kHz and below! :)

- Ross

I still enjoy tuning around although this time of year it doesn't get dark till relatively late so don't get much DXing done, that said I can just hear radio Caroline  on  648 Khz  and of course radio 5  radio Wales  radio Scotland  at nite. Minx radio on 1386 is about the only music station still on mediumwave darker niteswill bring the Hungarian and Rumanian stations  so not a complete dead lose yet. I could go on but I won't unless someone asks for info. I think AJ Jewsbury is right they probably replaced bits until the fault went. I think the faulty feeder come off the same transformer as my house but it's a different cable 

Did you ever receive BBC Radio Ulster on 1341 kHz from Lisnagarvey Transmitting Station in Northern Ireland?

The mast that was used is of an very unusual design and I'm not sure what the future holds for it, after BBC Radio Ulster discontinued its MW service.

Some information at the links below:

• https://en.wikipedia.org/wiki/Lisnagarvey_transmitting_station 
• https://www.lisburnmuseum.com/virtual-museum-lisburn/the-end-of-an-era-lisnagarvey-transmitting-station/
• https://www.bbceng.info/Install/Transmitter%20Projects/Reminiscences/Lisnagarvey/Lisnagarvey_Blaw-Knox.htm 

I might have a tune around the MW broadcast band after dark this evening and see what can still be heard - the weak station that I could heard on 1296 kHz earlier in the week sounded like it might have been foreign.

- Ross

Yes I used to hear the N Ireland transmissions regularly at nite sometimes with almost armchair quality reception. I think the masts are called Blaw Knox masts and as ýou say an unusual design popular with US commercial stations. The station on 1296khz is an Asian station transmitting from Ashton moss transmitter near Birmingham I think if memory serves it runs about 5.5 Kilowatts I remember it was usually stronger than the BBC world service which proves just how efficient the BBC areals at Orford nesss were. My daytime reception here is Radio Caroline but only just on 648khzBBC 5 from start point on 693 radio Wales  on 881khz radio5 from Bournemouth on 909khz Jersey on 1026 talksport weakly on 1053 and much stronger on 1089 Guernsey on 1116 some Indian  program from brookmans Park on 1458 and finally BBC Somerset on 1566. At nite of course things get much more interesting!

BBC Radio Ulster from Lisnagarvey had a radiated power of 100 kW and in the past I was often able to listen as far south as Dublin.

Did you ever receive Downtown Radio on 1026 kHz? It was broadcast from a small transmitter site at Knockbracken, just to the south-east of Belfast, with a radiated power of only 1 kW.

As for Orford Ness, I believe the BBC MW antennas there were directional towards the North Sea and the continent and as a result reception in the UK would have generally been poor, relying on whatever back-beam existed.

Interestingly, BS 6656 used to have a note that certain tables contained therin relating to the ignition of flammable atmospheres by radiofrequency radiation did not apply to '. . . locations on the seaward side of Orford Ness, Suffolk' but I think this may have been more to do with the exteremely powerful over-the-horizon radar station that was once there, rather than the MW transmitters!

- Ross

You could well be right about RF levels around Orford Ness I seem to remember that the cobra mist radar radiated about 3 Megawatts at various HF frequencys so would of created  RF spark hazards  even a distance away. Reminds me if a story I heard that construction work on a new sports stadium in arabia  was hampered by RF sparks from a metal crane hook caused by pick up from  1200Kilowatt mediumwave transmitter about a mile away! I never heard downtown radio on 1026khz here because radio Jersey uses the same frequency at 1 kilowatt its around 90 miles from here but is mostly a sea path  so it come in here with a surprisingly strong signal

That " extremely powerful over-the-horizon radar station" would be the Cobra Mist project. A truly misguided attempt to co-locate transmitter and receiver for an OTHR that was very expensive and was eventually scrapped without ever having really worked, An array of log periodic antennas pointing at incremental angles and many megawatts of towards the iron curtain.

The now declassified official report makes an interesting read for those who like details.

"To achieve sufficient signal-to-noise ratios  against the predicted noise background, the radar
was capable of very high transmitted power output. A peak power of 10 MW and an average power
of 600 kw were originally specified, although these figures were not achieved in practice. Such high
powers were incorporated in the design to compensate for the relatively low antenna gain of
approximately 25 dBs."

Mike

PS good OTHRs are like the Australian one Jindalee Operational Radar Network (JORN)