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:
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
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 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
Thanks. I already scanned through that, but I will go through it again in case I missed something. Mike🙂
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.
Pretty sure the measurement bandwidth is 50Hz-15kHz.
You might want to ask here:
FMtuners@groups.io | Home
Tuner Information Center - Vintage Stereo Tuners
List of EIA standards - Wikipedia
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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.
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!
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.
You may be aware that the 185-1975 standard is inactive-withdrawn. IEEE will sell you a copy for $60 though. 185-1975 - IEEE/IHF Standard Methods of Testing Frequency Modulation Broadcast Receivers - IEEE Standard
There is a critique of the standard at Updating IEEE 185-1975. The author may be able to help you further on standardized testing.
There is a critique of the standard at Updating IEEE 185-1975. The author may be able to help you further on standardized testing.
Yes, I saw it was for sale and did not feel that as audio hobbyist/amateur I wanted to part with $60 for that info. Thanks 😱
Thanks all for the info. Searching around I eventually found that the info I was looking for was in the old copies of the Pioneer Tuning Fork service guides I downloaded a long time ago. 🙂
The Institute of High Fidelity used to publish test standards for amplifiers and the like but they went out of business years ago. I did a search on IHF standards but didn't find anything.
Thanks Ray,
Pretty sure the modulation level for distortion testing tuners is 100%. Now looking into why the measured THD varies so much with modulation level - a minimum of ~0.09% at about 50kHz FM going up to around 0.3% at 75kHz and 30kHz. Puzzling...
Pretty sure the modulation level for distortion testing tuners is 100%. Now looking into why the measured THD varies so much with modulation level - a minimum of ~0.09% at about 50kHz FM going up to around 0.3% at 75kHz and 30kHz. Puzzling...
I got a sx-780 and sx3700 playing to near cd quality on stations with no compression.
you need a strong 88 to 90 mhz station 96 ish and 107 mhz. then turn the trims until all have about the same sensitivity. This will get you real close to ideal.
you need a strong 88 to 90 mhz station 96 ish and 107 mhz. then turn the trims until all have about the same sensitivity. This will get you real close to ideal.