Morse audible over Radio 4 LW last night
 

A bit of an oddity.

I was listening to Melvyn Bragg on Radio 4 LW last night (so it must have been between 21:30 and 22:00) on one of my faithful DAC90As, when I heard very clear Morse code. It seemed to be a handful of letters, a pause, then some more letters, rather than a stream of words.

Reception of Radio 4 is excellent here in Oxford at the moment, but the Morse was loud and clear too.

Any ideas what's going on? There are no radio hams nearby AFAIK. The only bother I normally get is SMPS hash from next door, which is why the radio is where it is, against an external wall rather than the party wall.

N.

Re: Morse audible over Radio 4 LW last night
 

I apologise in advance, but I can't help thinking of the ghost of that Oxford-based Detective Chief Inspector. The handful of letters weren't by any chance "dah dah, dah dah dah, dit dah dit, dit dit dit, dit", were they? :D

Re: Morse audible over Radio 4 LW last night
 

Ha ha! It's not impossible, but I don't think it was that!

Re: Morse audible over Radio 4 LW last night
 

Spies. They're still about, you know!

Re: Morse audible over Radio 4 LW last night
 

Have you tried another radio tuned to Radio 4 LW whilst you can hear the morse signal on your Bush DAC90A?

Re: Morse audible over Radio 4 LW last night
 

MCW?

NDB somehow?

Lawrence.

Re: Morse audible over Radio 4 LW last night
 

Wonder if it was someone experimenting on 472 - 479 KHz band. That's CW and close to the IF frequency of the DAC90A

Re: Morse audible over Radio 4 LW last night
 

Presume DAC90A is Osc high side. 198+470(guess) is 668kHz.

2x 668kHz is 1336kHz, add the IF again to 1806kHz. That is near the bottom of top band and
somewhere high power CW might be found on winter nights.

A fast callsign & report exchange might not be very many characters. A short burst (callsign), pause, a longer burst (signal report & maybe location), pause (the reply from other end), a couple of characters (maybe just 2 dits), the end.

Re: Morse audible over Radio 4 LW last night
 

A spot of IF breakthrough from something nearby or powerful, as has been mentioned? Or an LO harmonic mixing something somewhat higher in frequency that hasn't been sufficiently rejected by the front-end into the IF? I recall that it wasn't unusual when listening on 198 (or 200!) kHz at night, particularly on a simpler, cheaper transistor set, to hear something like Moscow Nights or Tirana's mournful ident faintly in the background on quiet passages. I assumed that this was an artefact of slightly "messy" and harmonicky single transistor mixer/oscillator stages with incidental RF selectivity mixing something of a porridge of spectrum into the IF amp. Some of the Cold War senders had fearsome power and could be quite difficult to keep out of things! I'd expect better from a UCH42, though.

A bit of a puzzle there, though.

Re: Morse audible over Radio 4 LW last night
 

Not saying this is the cause but sometimes cross modulation can happen due to the Luxembourg effect.

Lawrence.

Re: Morse audible over Radio 4 LW last night
 

Yes I agree probably IF break thru or possibly a second harmonic of something from the very long wave TXs that lurk in the VLF part of the spectrum but my best guess is the IF thing. Hearing midnite in Moscow as a background to 200 KC/s is not a receiver fault in days gone by the USSR built high power TXs in Moscow and Leningrad to stop listeners there from hearing BBC world service which was on from midnite or thereabouts on 200 KC/s

Re: Morse audible over Radio 4 LW last night
 

If it's radio amateur Morse and in short bursts, it could be someone calling 'CQ' to invite contacts from other amateurs. If you hear it again, it might be worth seeing if it is. Typically: 'CQ CQ CQ DE (callsign times 3) K'. EG: CQ CQ CQ DE G4EBT G4EBT G4EBT K'. Even for someone who doesn't know any Morse code, it's as easy to recognise the melody of CQ as it is to recognise SOS.

If you go to 1.35 at this link cartoonish link you'll hear what CQ sounds like:

https://www.youtube.com/watch?v=mj99pja8B7o

Utterly irrelevant to this thread, but perhaps worth mentioning that 'CQ' does not mean 'Seek You' as many believe. It wasn't even derived from English, but from French (just as 'Mayday' is derived from French m'aidez "help me"). CQ was adopted by Marconi International Marine Communications Co in 1904. It had been in use for some time by land telegraphists and is derived from "sécu" - an abbreviation of the French word sécurité to identify messages of interest to all stations along a telegraph line.

Marconi International Marine devised 'CQD' to mean 'All Stations Distress Call' which was already being used internationally. It was soon replaced by the 'Notzeichen' (distress signal) SOS, used by Germany from 1905 and adopted internationally from July 1908. Jack Philips - the radio operator on the Titanic in 1912, initially sent CQD, which was still in use on British ships, then his junior officer said 'why not try to new-fangled SOS?' Hence, Philips alternated the two. (He drowned - his junior survived).

https://en.wikipedia.org/wiki/CQD

https://en.wikipedia.org/wiki/SOS

(In Morse code, SOS is sent with no spaces between the letters).

Waffling and dribbling again. Sorry - I'll get mi coat :-)

Re: Morse audible over Radio 4 LW last night
 

Q...God Save the Queen, one of the first things that was drummed into us when learning morse code while studying at The College of International Marine Radio Telegraphic Communication’s in Manchester...aka Alf's Academy:

https://www.radioofficers.com/traini...ar-manchester/

Long time ago8-o

Lawrence.

Re: Morse audible over Radio 4 LW last night
 

The Soviets had 81 jamming stations for the BBC HF transmissions spread across the Soviet Union - not sure they attempted to jam 198kHz. Following the outbreak of 'Perestroika' around 1987, the Western broadcasters and the Soviet Bloc broadcasters got together following their respective conferences and it was put to the (former) Soviets: 'why don't you use YOUR (jamming) stations to broadcast OUR programmes?

And they did!

But when the Soviets did jam, pre '87, they used sophisticated methods that 'messed with your head' by using programme content that replicated audio and a mixture of other tones, detracting from the information carried in the jammed broadcast - don't think CW was ever used.

Re: Morse audible over Radio 4 LW last night
 

Apart from a very brief jamming station 'ident' signal, which Tatsfield, later Caversham, noted and recorded to try to locate the jammer concerned (just checked my notes...).

Re: Morse audible over Radio 4 LW last night
 

Is it possible that the observed signal was some form of emergency coded information being transmitted to HM submarines ? or to other parts of our armed forces.

Re: Morse audible over Radio 4 LW last night
 

I guess spurious Morse could be resolved on a receiver without a BFO by beating with the wanted signal - I recall having heard Morse in the background on early-80s medium-wave car radios when driving past various large transmitting-stations in the Midlands - the usual effect was recognisably Morse, but reproduced as 'thumpy' level-shifts of the program I was listening to, presumably as the extraneous carrier affected the receiver's AGC.

Re: Morse audible over Radio 4 LW last night
 

Without a recording (or transcription) of the morse we are unable to tell you what it was. May well be an amateur (not even local) beating with R4 due to a mixer issue in your radio, spurious from the transmission, or maybe one of the various beacons below the broadcast band. If you hear it again record it, many of us can copy morse..

Dave
G3YMC

Re: Morse audible over Radio 4 LW last night
 

I had an interview at Brook's Bar, well more of an informal careers chat, I was still at school. Probably 1968. All I really remember was the the aptly named Collage secretary!

Re: Morse audible over Radio 4 LW last night
 

Goodness, I live <5 mins from there and have passed that building most days on my way to work for 25 years - never knew the history. The area has been changing - people familiar with the place might be amused to know that Hyde's brewery has been converted into a gated community of yuppie flats! :)