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I have a schematic I am looking at:

enter image description here

What does the NF on the resistor mean?

Trev347
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1 Answers1

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Not populated — don't put any resistor there. Or in the case of whoever wrote this schematic, "not fitted" or something like that.

As the doc says, this is a spot where you can put a pi network, but with the R1 and R3 footprints unpopulated, and R2 0-ohm, you get a "direct" (no matching network) connection between LTE_ANT and J1.

hobbs
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  • What is the point to putting a resistor that you should not place in the schematic? Why not just leave it out? – Trev347 Jul 13 '23 at 01:55
  • Somewhat curious that they'd call these "R1, R2, R3", where the intended PI matching network (if needed) would be populated with "C1, L2, C3". – glen_geek Jul 13 '23 at 02:39
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    @Trev347 Because if you want to change the frequency response of the filter, you may want to put something there. – Hearth Jul 13 '23 at 03:03
  • @glen_geek agreed. It doesn't seem very carefully done. I understand R2 since it's populated with 0R, but it's still unclear. But I don't see how the intent could be anything else :) – hobbs Jul 13 '23 at 03:28