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Old 22nd Nov 2022, 7:51 pm   #254
regenfreak
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Join Date: Nov 2018
Location: London SW16, UK.
Posts: 655
Default Re: 6-gang FM stereo tuner heads

Quote:
Houston i have a problem here, the maths does not add up in the plots, if OP is the output frequency, the equation of the straight line would be:

OP = -nRF + mLO
-n is the slope , mLo is the y-intercept.or input RF = 0 hz and m = 1, OP = mLO=3.6GHz. In the graph, the lines all intercept at 6GHz, I am confused now and need to go away to do some exercises to clear my head.
Ok, the muppet overlooked the LO slider. Now the numbers add up.

This old paper based web works similarly except they non-dimensionalize by dividing the output OP and RF frequencies by LO:


https://www.rfcafe.com/references/el...r-spur-web.htm

OP = mLO + nRF

Op/LO = n RF/LO + m

n = slope

m = y-intercept
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Last edited by regenfreak; 22nd Nov 2022 at 7:56 pm.
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