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European Pirates and Private Stations / Re: mystery station ? 6270.0 0320 UTC 29 May 2018
« on: May 29, 2018, 1957 UTC »
Hello Ray - this is a topic for the technical segment, but I will describe my experience because once again the issue of "ghosts" appears.
I often see mirror or intermodulation signals on my RTL.
I noticed that the change (increase) of the Input Sampling Rate reduces or eliminates them. Unfortunately setting for example 3,2 Mc reduces the signal strength. Usually these unexpected signals are not exactly according to the frequency grid, which raises suspicion about their actual existence.
Momentary tuning of the receiver so that it is different LO FRQ and return to the observed signal also often shows that it no longer exists. The same is obtained by changing the Setting LO <> Tune Offset. Is this a real signal also verified by listening on the Icom PCR 1000 receiver which due to different architecture will not reproduce the "ghost" signal. Using a signal attenuator at the RX input does not solve this problem. I have to run a set of HF 12 pcs with bandwidth filters (2MHz bandwidth) and I hope to significantly reduce these signals.
I have set LO <> Tune Offset 1MHz and sometimes a strong station from other band at such a distance gives me a mirror.
Write about your experiences. But at 6270 something was playing with me too
.
73!
I often see mirror or intermodulation signals on my RTL.
I noticed that the change (increase) of the Input Sampling Rate reduces or eliminates them. Unfortunately setting for example 3,2 Mc reduces the signal strength. Usually these unexpected signals are not exactly according to the frequency grid, which raises suspicion about their actual existence.
Momentary tuning of the receiver so that it is different LO FRQ and return to the observed signal also often shows that it no longer exists. The same is obtained by changing the Setting LO <> Tune Offset. Is this a real signal also verified by listening on the Icom PCR 1000 receiver which due to different architecture will not reproduce the "ghost" signal. Using a signal attenuator at the RX input does not solve this problem. I have to run a set of HF 12 pcs with bandwidth filters (2MHz bandwidth) and I hope to significantly reduce these signals.
I have set LO <> Tune Offset 1MHz and sometimes a strong station from other band at such a distance gives me a mirror.
Write about your experiences. But at 6270 something was playing with me too
.73!
You run nicely, cool jingles
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