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Old 10th Jul 2022, 11:36 pm   #92
G0HZU_JMR
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Join Date: Sep 2010
Location: Cheltenham, Gloucestershire, UK.
Posts: 3,077
Default Re: 6-gang FM stereo tuner heads

Yes, mismatch uncertainty can become very significant for some measurement tasks. The VNA calibration is very important in order to reduce systematic errors and I usually use a lab VNA and a decent mechanical cal kit or an Ecal module for stuff like this.

The little nanovna seems to work very well up to about 50MHz then the performance falls off after this. Even a modern lab VNA will struggle to measure some of those resistors up into VHF and UHF. Across the HF bands a decent VNA can deliver remarkable performance but above this it becomes increasingly difficult to correct the systematic errors mathematically.

The IEEE paper sounds interesting. I can access this tomorrow at work.
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