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DTT spectrum in "high input"

 

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Hi all. I come to this group from the nanoVNA group. I don't have a tinySA yet but I will surely buy one. I would like to see a sweep of the "high" input of the analyzer scanning the UHF DTT band to know how the 8MHz channels are displayed without the 433.9MHz bandpass filter. Thanks in advance
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EA1AWY? Javier Muriedas? (Gijón, Asturias, Spain)
 

Something like this?


Two adjacent DTT channels
  

Thank you very much Eric, for your quick and efficient response. It looks better than I thought. I believed that the channels would appear widened when received above and below the LO frequency with the available IF being less than 1MHz. It also supposed that there would be a "hump" in the central part when adding the powers of both recepcioners (above and below LO).
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EA1AWY Javier Muriedas (Gijón, Asturias, Espa?a)
 

In high input mode there is some amount of mirror suppression, at least 30dB.?
Not good but usable for certain measurements
 

Is that high input mode mirror supression “ tweakable”, (eg with a balancing variable capacitor), or tiny twists of enamelled wire?

Steve, ?G7PSZ
 

Nope, its fixed DSP inside the a chip
  

Thanks again EriK. I can't see how he can do it, but the important thing is that he does it. 30dB is not a panacea but it is pretty good. In a TV antenna installation the decoding will be satisfactory with 30dB C / N ratio and normally we will not find much more than that. Therefore, we could use the tinySA as a "poor man's field meter" for amateur use, with portability and value for money, unbeatable price.
Congratulations
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EA1AWY Javier Muriedas (Gijón, Asturias, Espa?a)
 

I used the tinySA to debug dbv-c signal quality on my cable distribution. Easy to spot bad splitters or overload due to amplifiers

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