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Wishlist: Useful features for the next software version

By hamuma •  2017-02-08 23:30:59 •  468 clicks
If an antenna is connected directly to the analyzer, the approach of the operator influences the measurement.

Is a remote control planned? E.g. via USB or network?
Also a time-delayed measurement would be very helpful.

connected  software  features  directly  network 

2 Reply | until2018-07-17 21:14Add a reply
    g7psz  2017-05-23#1 -Reply

    Half my replies seem to vanish on this bbs.

    So I will type again......

    I have now repaired my kc901s, so the urge to buy the updated 901v has been moderated by my financial constraints. I was sorely tempted because of the selectable resolution bandwidths in spectrum analyser mode.

    I use my 901s presominantly as a portable spectrum analyser (chasing qrm from switch mode psu, led lights etc), despite it not being its primary design purpose. I am mindful of the missed signals because of the finite steps in the sweep.

    However, further resolution bandwidths below 3khz (eg to 100hz) would allow inspection of individual transmitted signals and study of intermodulation products of ssb amplifiers etc. A sweep of only 20khz is needed for this, which would not result in "lost" signals.

    My original plan was to feed the signal to be inspected, along with a suitable local oscillator into a balanced mixer and look at the low frequency output via a pc or into a handheld tablet using its internal 16 bit adc. My ipad has a superb real time spectral display program with apparently 80db range and a resolution bandwidth about 10hz.

    Alternatively could the 901 be modified to provide a low frequency analogue output (before its adc) to allow connection to the microphone input of my ipad?

    This output could also be used to actually listen on headphones to demodulated signals when the 901 is on a single frequency (not sweeping).

    Steve Laurence G7PSZ

    VK3NH  2017-02-09#2 -Reply

    I have also noted that issue but for a VHF/UHF portable antenna it is indicative of the true antenna performance in normal use.

    Some observations about your measurement issues but not related to you question of whether a remote control function can be achieved which the site controller can answer.

    1/ The unit should not really be relied upon to provide a good ground plane for frequencies much below say 400MHz. That in itself makes the measurements prone to near field body effects as they would for a handheld dual band radio.
    2/ If you set to the maximum number of sample points at the slowest speed and single sweep mode then you should have adequate time to move away while the measurement is being made and then come back to observe the result.
    3/ By adding a reference cable (and putting known length and velocity factor into the KC901V) and then do the Open Short Load user calibration before putting the antenna on a suitable plane away from the unit or non metallic support if it is say a yagi antenna.

    I hope these suggestions are of some use to you.

    regards Noel


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KC901 serial VNA