FM/PM/AM accuracy - RF Cafe Forums

 Post subject: FM/PM/AM accuracy

Posted: Tue Sep 21, 2010 4:16 am 

Dear distinguished guests of the forum,

With reference to the 8902A specifications especially the FM/PM and AM accuracy published in the document , i would be obliged if anyone here can point out the differences in the said specs compared to the ones published by some accredited calibration labs using the same instruments.

For an example , the Freq Modulation accuracy(as stated in the 8902A spec sheet) is given as +2% of reading + 1 digit at freqs ranges 250kHz - 10MHz at rates 20 Hz -10kHz at deviation less than 40kHz peak.
But Agilent in its scope states it at 0.024FM +10Hz peak?
But using the same instruments , the accuracy should be 2% + 1 digit ,agreed?
Can i rewrite the accuracy as 0.02FM + 10 Hz peak?

How about Amplitude Modulation accuracy then?
The 8902A specs state +2% of reading + 1 digit at freq range 150kHz -10MHz at rates 50Hz - 10kHz and depths 5%-99% but again Agilent scope states it at 0.025 AM + 0.14 %......
Should it not be 0.02AM + 0.1% only?

I hope someone can help explain this difference?

Rgds
Ruben

 Post subject: Re: FM/PM/AM accuracy

Posted: Wed Sep 22, 2010 9:17 am 

I've seen the difference in semantics on a lot of certificates from cal labs. Pick a cal lab from a Google Search and call them to ask. You might even try calling Agilent and asking them. Agilent soaks you for products, but is usually pretty good about getting answers.