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Old 1st Aug 2021, 10:18 am   #42
regenfreak
Hexode
 
Join Date: Nov 2018
Location: London SW16, UK.
Posts: 379
Default Re: DIY FM tuner with 6CW4 nuvistor and ECC85

Thanks for the explanation.

The IC-7300 uses 16 bit high-speed direct sampling ADC that can capture the RF signal.

Correction: Ziegu G90 uses lower cost 24-bit mixer type ADC, it is not direct sampling.

The greater the bits, the more the dynamic range(the less quantization noise from the ADC);

16 bit ADC has 95db dynamic range
24 bit ADC has 144db dynamic range

Correction: The Marantz 20B and 10B use two-stage grounded grid RF amp with ECC88 and they are not in cascode.

I find this very intuitive, visual explanation of I and Q:

http://whiteboard.ping.se/SDR/IQ
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