June 2010 Recordings from Central/South America. Time signal from Guayaquil, Equador. 3810KHz. This signal has returned, it transmits LSB with inserted carrier so a receiver set on CW will pickup the 1KHz time pips on 3.809KHz. These are now every 10 seconds, with an announcement before. These pips are often audible in the morning when the band is quieter. Sometimes the announcements may be heard using LSB 3810. This path is showing different results than others. There is little sign of a dusk enhancement, signals gradually rise and a definite peak after my dawn is not uncommon. I feel this may tend to be seasonal, a second year's research is needed! As with all my observations I can only say that I assume the transmitter identity, that power and antenna remains the same and although the effect of interfering signals are usually obvious I can only monitor irregularly, maybe an average of one short period per night.
Looking for other signals from this direction From PTSW I find [Honduras on 3340.0KHz. A signal that has the expected properties is seen but is likely to remain one that will not be positively identified, but it has got strong enough to hear some audio. First seen at about 3340.03, now drifted down to about 3339.97KHz.. This has been absent for some time.]
Marituba, the Transmitter site of R. Cultura Ondas Tropicais, Belém, Pará Brazil, on 5045KHz And another from South America. R.Difusora de Maca, Brazil. on 4914.97KHz. Jan 2010 around 4914.98KHz. Another station close to the frequency (~4915.0-4915.02KHz) is shown with a light blue trace. I suspect this to be another Brazilian, maybe R.Anhanguera, usually fading in a little later than Maca but even this is not constant, showing variations in propagation over a relatively small distance.
Although Macapa and Marituba have similar paths and frequencies the propagation observed from them often looks different. Note I have been playing with transmitting WSPR. My low power signals cause spikes on some charts but the overall picture is not affected.
