Justin:

You’re exactly correct. I’m shooting for 15.247.a.2 and 15.247.e to achieve (or approach) the 1W limit allowed in 15.247.b.3.

I didn’t have spur reject off, so perhaps that’s the difference. I believe I had all other settings the same though. I’ll retest this afternoon.

In this gem of a document from the FCC: https://apps.fcc.gov/eas/comments/GetPublishedDocument.html?id=237&tn=158724

… Section 7.3.4 explains one accepted method of testing PSD. They suggest using RBW of 3 kHz (which I am) but a VBW of 9 kHz. Spike won’t allow me to set VBW > RBW in any case. Is this going to lead to any inaccuracies in measurement?

I don’t need cert-quality measurements, but I do want realistic numbers from this pre-scan, so I know how much margin we have before hitting the 8 dBm limit.

Thanks very much.

Chris

Is there any resolution to this issue? I’m attempting to make the same measurement, and I believe I’m finding the same issue – 3 kHz PSD is several dB below the expected value.

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