{"id":17862,"date":"2016-03-22T09:38:02","date_gmt":"2016-03-22T13:38:02","guid":{"rendered":"http:\/\/swling.com\/blog\/?p=17862"},"modified":"2016-03-22T09:38:02","modified_gmt":"2016-03-22T13:38:02","slug":"bad-signals-transmitters-in-need-of-care","status":"publish","type":"post","link":"https:\/\/swling.com\/blog\/2016\/03\/bad-signals-transmitters-in-need-of-care\/","title":{"rendered":"Bad Signals: Transmitters in need of care"},"content":{"rendered":"

China Radio International via Radio Havana Cuba<\/strong><\/p>\n

\"Click<\/a>

Click to enlarge<\/p><\/div>\n

Each morning, I enjoy listening to Radio Australia on 9,580 kHz, but I’m forced to tune elsewhere\u00a0due to interference\u00a0when China Radio International starts broadcasting on 9,570 kHz, via Radio Havana Cuba’s relay.<\/p>\n

Hypothetically I should be able to mitigate any adjacent interference from CRI by listening to Radio Australia’s upper sideband. But unfortunately,\u00a0RHC’s transmitters spew spurious emissions a full 20 kHz on either side of their carrier. It’s most annoying.<\/p>\n

Here’s what RHC\/CRI’s 9570 kHz signal sounds like on 9560 kHz<\/a>:<\/p>\nhttp:\/\/swling.com\/blog\/wp-content\/uploads\/2016\/03\/Rec-9.559999MHz.mp3<\/a><\/audio>\n

Here’s what my waterfall looked like when CRI signed off:<\/p>\n

\"CRI-Spectrum-2\"<\/a>Notice how clear the 35 kHz waterfall window became (that’s Radio Australia centered on 9850 kHz):\"CRI-SignOff\"<\/a><\/p>\n

The reason for this is clear: obviously, some of RHC’s transmitters are in need of care–and they’re not the only ones.<\/p>\n

Radio Cairo<\/strong><\/p>\n

I’ve received a number of requests from Radio Cairo to post notices about their English language broadcasts. Normally, I’m quite happy to post press releases, but in each case I’ve mentioned that their English broadcasts are almost impossible to understand. For years, RC has had a\u00a0problem with AM modulation (I assume) and, to my knowledge, have never addressed it.<\/p>\n

I’ve sent RC feedback on a number of occasions; in response, I’ve received only the inconclusive reply\u00a0that they’re\u00a0“looking into the situation.”<\/p>\n

To underscore\u00a0the point, on\u00a0Sunday Andrea Borgnino shared the following video\/audio of Radio Cairo\u00a0via Twitter<\/a>.<\/p>\n

\n

Radio Cairo & worst am modulation @SWLingDotCom<\/a> @LondonShortwave<\/a> @John_Northants<\/a> @UlisK3LU<\/a> pic.twitter.com\/o0aRCkPtwt<\/a><\/p>\n

— Andrea Borgnino IW0HK (@aborgnino) March 20, 2016<\/a><\/p><\/blockquote>\n