The fact that this station is able to instantly switch between AM and FM (no silence between modes) really has me wondering what kind of equipment they are using. Below is something I previously wrote about this station, with some slight modifications
This is the Brazilian station that appeared for the first time Friday night (SEP 17 in UTC). It has poor modulation and has appeared on three frequencies, 6979.8, 6950v, and 6960v kHz. On 6979.8 the carrier is easily seen on the waterfall (and drifts only a little bit) and audio is just slightly distorted. On the other two frequencies distortion is very bad and there are multiple lines on the waterfall near where a carrier should be. One of them is a carrier, but I am not sure which one it is or how the others effect the sound when listening in AM mode. It sounds very different from how I would expect it to based on the waterfall. Tuning in SSB is impossible, it always sounds weird and has a lot of buzz. I think it is likely using a homemade crystal controlled transmitter that is designed poorly. I am not sure why modulation is so much worse on the lower frequencies, maybe damaged crystals? I have added two pictures below of the modulation. I think it is worth keeping an eye out for this station.
I have never heard of a homemade transmitter that can switch modes like this, but I have also never seen ham equipment with such poor AM modulation. This is certainly very unusual. I realize now I have also heard this station in FM before but I thought I was hearing a ute. I have no idea what kind of equipment they are using but it must be different from anything I have heard of.
Topic: UNID (Brazil) 6960 AM/FM 0030 UTC 28 SEP 2022 (Read 962 times)
