Quote:
Originally Posted by Nuvistor
What I liked about them was their simplicity, just had to be aware of their limitations.
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About 20 years ago, I decided to investigate direct conversion for 80,40 and 20m. Using a mc1496 multiplier preceded by bandpass coils, on 80m I could achieve about 1uV sensitivity but on 40 and 20, it took off with audio oscillations. The only way I could get 40 and 20m stable was to reduce the audio gain, which meant it would have compromised sensitivity on 40 and 20m.
I wonder what the sensitivity of this 20m dc receiver is? They don't seem to have published it in the article.
I have found the best method and with minimal complexity radio design is to go for a single conversion superhet, spec. is good throughout.