EMRFD Message Archive 8001

Message Date From Subject
8001 2012-12-28 08:29:33 Nick F Double balanced RF Mixers - 1dB compression point
Hi All,

I've done some more measurements on my double balanced mixers, this time the 1dB compression point. The results are preliminary, once I have better data I will update the document. Maybe I can get some feedback from people who have more experience, if the results seem plausible or not.
The updated document can be found at http://users.tpg.com.au/nfieraru/Electronics/RF_Mixers/Double%20Balanced%20Mixers.htm

8003 2012-12-29 03:43:06 ha5rxz Re: Double balanced RF Mixers - 1dB compression point
8012 2012-12-30 18:50:15 Nick F Re: Double balanced RF Mixers - 1dB compression point
Hi Peter,

My concern was more related to using a good method when performing measurements. We can get different results by doing measurements with different settings.
For example, if I apply a constant level from signal generator to the spectrum analyzer and I change reference level, span, resolution bandwidth, I can get a difference of 1dB in level measurement.
This does not mean that there is anything wrong with the instruments, just that some settings are not as good as other ones for a specific task. For example, if you have a multimeter and you set to measure voltage on 1000V range and then measure 0.5V, you will get a result, but your setting is not the most suitable for the value you want to measure.
Some papers are describing a method that involves moving a 10dB attenuator between input and output and slowly increasing the level until the 1dB compression point is reached. I used a different method, which is faster but probably less accurate. However, looking at the results, they appear good enough for as general informati