Wireless Waffle - A whole spectrum of radio related rubbish
Russia is the Tsar of Piratessignal strength
Thursday 19 January, 2012, 14:30 - Amateur Radio, Pirate/Clandestine
Posted by Administrator
Wireless Waffle has talked extensively about pirate radio in the past, from short-wave music stations, to Brazilian sat-jackers. But it seems that, of all the nations on the planet, the Russians hold the baton for being the biggest pirates of them all.

This story begins when reading the latest intruder report from the IARU Region 1 Monitoring System. The report indicated that there had been an intrusion into the 80 metre amateur band between 3.5 and 3.6 MHz by Russian pirate stations running AM. Now historically the Voice of Korea (the North Korean broadcaster) has been transmitting in the 80 metre band (or the 75 metre band as it's called in in North America) on 3560 kHz in AM and the immediate assumption was that these new signals couldn't possibly be Russian pirates, but must be the Voice of Korea and perhaps a few other stations trying to jam it. The IARU report, however, says that the carriers are very unstable and that the modulation is voices in Russian.

blue soldier red squareSo the only thing to do to verify this story is to turn on a receiver and have a listen. Having done this, there were no obvious signals in the 80 metre amateur band. Having previous heard pirates just below the band at around 3450 kHz, the tuning dial was slowly rotated to ever lower frequencies. Nothing. And then, at 3175 kHz, something. A weak carrier... no, two carriers alternating... both rather unstable in frequency. Switching the receiver to AM yielded weak modulation. A bit more tuning, to 3125 kHz and a much stronger AM signal with a Russian voice and a wobbly carrier. Hey presto!

But what are these odd signals? Are they military operators in a private net (if so, why AM and why unencrypted)? Are they some kind of harmonics or intermodulation? Googling didn't bring much until a page on Sparky's Web Blog was found. It seems that these are effectively the equivalent of Russian CBers but presumably using much lower frequencies given the large distances between Russian cities. The band is known as the тройка band ('troika' in English which has several meanings from 'three of a kind' to a sledge or fairground ride). The band runs from approximately 2900 to 3200 kHz which are internationally allocated to the Aeronautical Mobile and Mobile services.

red square blue squareThere are aeronautical frequency assignments in the band (2872, 2899, 2921, 2962 and 3016 are frequencies assigned to North Atlantic traffic for example), but these lower frequencies are less often used unless propagation makes it totally necessary. Oddly, the various frequency lists for the band show very little aeronautical use in Russia (other than Irkutsk on 3016 kHz) - a coincidence? Probably the pirates know this and therefore feel free to mess about in the aviation bands, knowing that the Russian authorities are likely to be little interested in their activities.

If you're in Europe, when it gets dark (and lower frequency propagation opens up over the continent), why not give them a listen. It's fun to chase the carriers up and down in frequency. If you speak Russian, perhaps you could provide some translation as to what on earth they are talking about!

P.S. You might also want to take a listen to 2920 kHz USB as this seems to be a common calling channel for the more technically adept Russian pirates.
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BBBBCC Rraaddiioo Ssccoottllaannddsignal strength
Friday 9 December, 2011, 15:17
Posted by Administrator
It seems that it's not just Rraaddiioo Nneeddeerrllaanndd that suffer from an echo on transmissions. It was a dreich day and being concerned for relatives who live in Northern Scotland, last night the Wireless Waffle receiver was tuned to BBC Radio Scotland on 810 kHz.

jenny bbc radio scotlandThe 810 kHz service is transmitted from three stations, two high powered (Burghead and Westerglen) at 100 kW a piece, and a lower powered fill-in at Redmoss at 5 kW. From the south of England, only the two higher powered stations are audible and during the evening are pretty much at similar strengths and lo! and behold, there was an annoying echo echo on the signal.

Where multiple transmitters operate on the same frequency, it is as important that the audio feeds are synchronised as it is that the transmission frequencies are. Where both can be received at similar signal strengths, any difference in frequency between the two causes an audible heterodyne (a.k.a. whistle) to be heard. If the audio is not synchronised, an echo can be heard. Any difference in audio delay between the sites should typically be kept below a few tens of milliSeconds if the resulting echo isn't to cause a loss of intelligibility.

There are many reasons why transmitters may have audio feeds that are not synchronised. For short-wave services, the feeds may be on completely different routes. This became a bigger problem for international broadcasters when short-wave feeder transmitters were replaced by satellites. For many years, the BBC World Service maintained a 24 hour English language service on 6195 kHz (these days it is used for a variety of different languages and is shared with other broadcasters too). In those halcyon days, different transmitters around the world were used to maintain the frequency and typically sites in the UK, Middle East and Singapore would share the honours. At times, however, some of these transmitters may be on at the same time. It was not uncommon for Singapore and one of the UK sites (eg Skelton, Woofferton or Rampisham) to be transmitting English language programmes at the same time. But Singapore was fed via satellite and Rampisham by direct land-line. The result - 'The news the news read by Damien read by Damien Trellis Trellis' - over most of the world inbetween the two sites. This was eventually resolved by adding in a delay to the UK feed at Bush House to bring the networks back into alignment.

It's a shame, therefore, that BBC Scotland haven't learnt the lessons of their sassenach colleagues and got their own delays sorted out. Not least, the national DAB network has to be synchronised to within microSeconds so sorting the medium wave network out ought to be child's play.

As they say in Scotland, 'Whit's fur ye'll no go by ye!'
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Radio Killer - Don't Let The Music Endsignal strength
Monday 28 November, 2011, 12:10 - Chart Predictions
Posted by Administrator
Here at Wireless Waffle we're working on something a bit special. A project that will help sufferers of broadband drop-out everywhere. Meanwhile, we thought you might like the latest offering from Romanian groovers Radio Killer, 'Don't Let The Music End' (lovers of 80's hi-fi will enjoy their web-site!)

It isn't as good as Lonely Heart which we plugged for chart success earlier in the year (and still think there's a chance it might make it some day), but it's nice to see an inventive video (ie one that isn't just scantily clad ladies a-groovin' and a-grindin'). And Radio Killer singer 'Lee Heart' has a very girl next door kind of look, which again makes a refreshing change from the 'less is less' attire of some other pop stars.

One ponderance we had was whether there was just a little plagiarism going on when they thought of the title, as it's precariously similar to 'Don't Let The Music Die' from fellow Romanian Inna...
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Another Radio Birthday...signal strength
Monday 17 October, 2011, 14:38 - Radio Randomness
Posted by Administrator
big net night 30 emIt's been a while since we discussed CB radio here at Wireless Waffle and it's not time to go over old ground now. What it is time for, is to dust of that old rig that's propping up the WiFi routers that are sitting in the corner of your garage, sort yourself out a twig, and join the birthday celebrations.

CB radio becomes 30 years old on November 2nd this year, and to commemorate this landmark, there is going to be a party called 'The Big Net'. Set your dial to Channel 30 (UK) or 27.89125 MHz if you prefer, and put out a call between 7pm and 9pm. Wouldn't it be good if the result was the discovery of a few old breakers who you had lost contact with. Or embarrassing if you happen upon a few old seat-covers! A big 10-4 on that one.

Keep the lipstick off your dipstick and the smokies off your tail, good buddies. 10-10 'til we do it again.
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