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Use the filter and Attenuator to test the VNA(Track scope) function in Antenna Analyzer

Use the filter and Attenuator to test the VNA(Track scope) function in Antenna Analyzer
I have measured the performance of the S2 port added to the EU1KY Antenna Analyzer.
1.Introduction -
6.Antenna Analyzer VNA(Track scope) Test (this article)
1.Comparison of measurement results between commercial instrument and AA for filter
1.1 45.1 Mhz
I used a filter on a Motorola radio.

The filter is attached to the socket.

Measurement result of AA

Testing on a Spectrum Analyzer with signal generator

Measurement result of Spectrum Analyzer with signal generator

 The characteristics of the filter are similar to each other when viewed with AA and a commercial instrument.

1.2 50.1 Mhz
50.1Mhz Filter from YAESU FM transceiver.

Measurement result of AA

Measurement result of Spectrum Analyzer with signal generator


I used the attenuator to check the measuring range.
Connect the attenuator to S1 and S2.


 I set the range from 1 to 100 MHz.


 The measurement result indicates -5dB.


 The measurement result indicates -5dB.

-25 dB

 It is -25dB which starts the problem at 80Mhz or higher.
I recommend that the filter test be done at 70Mhz or less.
When measuring within -25dB, all frequencies are available.

I changed the frequency range from 1 to 40 MHz.


Measurement is possible up to -50dB, Most filter measurements are possible with -50dB.

-60dB (The maximum value of my attenuator)

 Measurement is not possible up to -60dB.


Maybe if you have a more sensitive attenuator, the range you can use can be measured even wider.

If you measure up to -25dB, you can use it at most frequencies. If you make a filter of 60Mhz or less, you can measure up to -50dB.


    it will be nice if you can make cursor vertical lines right and left if you determinat the filter bandwith so that you can set bouth lines left or right
    but in all good job nice .
    regards vojko
    de S52E

    1. Thank you for your good opnion.
      Maybe it would be good to compare dB. I will put the feature in the next version.

      Ian KD8CEC

  2. You have been busy Ian!
    It looks excellent. I will definitely be doing the transmitter mod on my EU1KY in the near future.
    Gerry / EI8DRB


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