What's happening with the CR95HF RX resistance?

RDien · ‎2022-02-08

If you look into the AN4327 CR95HF transceiver antenna tuning circuit with EMI filter you see:

I assume this means 22 pF capacity in parallel with 80 kOhm resistance. But when you open the recommended Excel sheet you see:

Until this moment this was supposed to be 1 gOhm. And finally you open the CR95HF Datasheet to check the value and there you see this:

Can anyone tell me what's the correct value finally?

Brian TIDAL · ‎2022-02-10

Hi,

the value to be used is 100 kOhm as specified in the Datasheet. The value in the Excel sheet is a typo but as soon as the resistance value is very high, the impact of having 80kOhm, 100kOhm or 1GOhm on the various formulas is insignificant.

Rgds

BT

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Brian TIDAL · ‎2022-02-10

Hi,

the value to be used is 100 kOhm as specified in the Datasheet. The value in the Excel sheet is a typo but as soon as the resistance value is very high, the impact of having 80kOhm, 100kOhm or 1GOhm on the various formulas is insignificant.

Rgds

BT

In order to give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

RDien · ‎2022-02-11

Hi, Brian!

Thanks! I've checked the infuelce and it turned out to be negligiblе just as you advised. When you are newbie and something goes wrong you tend to recheck every number you are in doubts about.

Kind regards!