FCC question

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Anonymous
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We are struggling with a puzzling situation in a product weeks away from shipping. We are using an FCC certified module in our product and when we use the manufacturing firmware via UART, our Spectrum Analyzer output looks exactly like the expected waveform. (40db difference between the 2.4Ghz and side lobes), however when we use the module in normal mode, in Max Hold mode, we see unexpected big side lobs. We do not belive this is a mistake with our hardware design so we are really puzzled.

I have a few questions:

* Using manufacturing mode, we can easily pass FCC test but we are worried we will have a problem if somebody would pick our product and test in normal operation. Considering we have no previous experience passing FCC with this type of module and frequency, are we missing something? (i.e. are we worrying unnecessarily?)

* Could this be a bug in operational firmware (or BRCM firmware) whereby it amplifies the sidebands ince the BPF is not working or working in a way it is not optimal.

I would appreciate if you could comment.

I attached the two waveforms. Manufacturing mode, SA output and normal oepration SA output. These are taken with near field probes.

[ATTACH=CONFIG]172[/ATTACH][ATTACH=CONFIG]173[/ATTACH]
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