Saturday, April 10, 2010
Measuring Latin American frequencies
During a few nice mornings in March I made some more offset measurements of the typical (and some more rare) stations of Colombia (& some other Latin American countries).
Especially on March 26th during a nice opening to Colombia favouring Manizales - Cali area, quite a few signals were well above audio level making IDing also by audio possible. The list of the statations heard is on picture below the article. The band was captured simultanously by IQ- and SDR-14-receivers at the King´s Village QTH covering 1190 - 1580 kHz. I have kept also one IQ on at home more to review the current conditions and make some observations during the sunrise period (usually about 15 minutes by daily basis) with a ALA100 loop (3x7 meters) in the garden. Although the urban RFI is heavy. sometimes signals do make their way up from the noise. On 26th March nice signals from some of those Colombians were noted also at home. The clearest was Sonora Cali mixed with Maria Manizales on 1500 kHz. At the picture you can easily see the slight drift of Maria and Sonora closing down (a clip with the Sonora sign off with QRM of Radio Maria).
The second figure shows a three days analysis on 1540. It is very easy to do with the SpectraVue automatically just to "listen" afterwards with waterfall and "allow file chaining" on. All measurements are done on a resolution of 0.19 Hz, but there is a calibration error of (below) 1 Hz. On 1540 it was nice to note that besides the common Bahamas (dominates during conditions favoring the Caribbean/Colombia) or TurboMix Cajamarca (during conditions favouring Peru) a Colombian station on 1539.994(5) could be noted. The waterfall shows it being the dominant on March 26th.
The station turned out to be Radio Cóndor Manizales which could be an "easy guess" as Mainzales was also strong on 1450.027 (no ID though) and 1500.005 (Maria). Thanks to Henrik Klemetz (again) to solving the ID!
On the bigger view a station on 1540.154-5 can be seen. This was first noted in Sweden by Gert Nilsson. On March 26th the close down was at 04.17 after instrumental music. A Peruvian or from Bolivia? Any ideas?
Remarks 17 April: According to Swedish DXers the station is Radio Corporación, La Voz de Cerro de Pasco (Tnx TJ, HK)
The whole list (mainly 26 March & a few others can be found by clicking the text below)
The list of offsets (google docs).