FM Tuner performance measurement guideline

mikebeth

Member
2016-05-10 10:02 pm
PA
Hello all,
Does anyone have information regarding the measurement parameters to be used in making Tuner performance measurements as per manufacturer spec's. Just for instance:

  • For FM Tuner distortion @65dBf 1kHz mono, what level of FM peak deviation is specified?
  • For FM stereo measurements what is the 19kHz pilot level? 10% ?
  • For FM stereo distortion measurements is the MPX generator set to L=R, or is only the channel under measurement (L or R) modulated?
  • What is the measurement bandwidth specification? 50-15kHz?
These are just a few of several questions that came up this morning while measuring an FM tuner I just aligned for comparison to the manufacturer spec sheet. Changing any of the above settings changed the levels measured.

These are the kind of details that I need to sort out to make tuner measurements for publication. A reference or link to a published guideline would be awesome and most appreciated. I have not found such a guideline on-line so far. Thanks, Mike
 

mikebeth

Member
2016-05-10 10:02 pm
PA
Many years ago, I remember seeing either an hp or Tektronix ap-note on FM tuner measurements. Unfortunately, I don't have it. Maybe google will help find it.


Thanks. From your suggestion I found a manual for an HP 8920 that has information on making measurements which will be helpful.
I am hoping to find an official standard like IEEE xxx.xxx that lays out the rules of the road so to speak.
 

mikebeth

Member
2016-05-10 10:02 pm
PA
Pretty sure the measurement bandwidth is 50Hz-15kHz.

You might want to ask here:
[email protected] | Home


Thanks. I'm making best guesses at settings right now, like the bandwidth spec. Did post at FMTuners and AudioKarma forums



Hoping to find an official standard so I can know what the manufacturers use (or should!) so our numbers are apples to apples. I can find what settings give me the best numbers with some trial and error, but that doesn't make my measurements "legal" so to speak!
 

mikebeth

Member
2016-05-10 10:02 pm
PA
http://w140.com/tekwiki/images/9/98/26AX-3582-3.pdf is an application note from Tektronix regarding FM broadcast measurements using a spectrum analyzer.


Thanks Bill, I'll check it out. I think a relevant publication may be


ANSI/IEEE STD 185-1975: IEEE/IHF Standard Methods of Testing Frequency Modulation Broadcast Receivers


but not it's something I have ready access to.