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Re: Antenna analyser

Posted: Fri Oct 27, 2017 7:10 pm
by Drachenfrucht
I have a question:

when we use Pavels' VNA application which jumper setting should we set at IN1 port ? The default setting is LV (LowVoltage). There is also the option to use HV (HighVoltage) or even jumper settings 2-5 to bypass the attenuator.

Should one use LV or 2-5 jumper setting to bypass the attenuator? What is best and suggested ?

Re: Antenna analyser

Posted: Sat Nov 04, 2017 9:01 pm
by Drachenfrucht
noone?

Re: Antenna analyser

Posted: Thu May 17, 2018 9:47 am
by sq3rx
Can anyone suggest jumper position during VNA operation ?

Re: Antenna analyser

Posted: Thu May 17, 2018 10:49 am
by pavel
sq3rx wrote:
Thu May 17, 2018 9:47 am
Can anyone suggest jumper position during VNA operation ?
The LV position should be OK.

Re: Antenna analyser

Posted: Thu May 17, 2018 11:48 am
by sq3rx
I am wondering is it safe to use it with baypass. :idea:
I use RP as skimmer serwer with metal case, so open it every time when I need to use vna is difficult.
Or maybe I can change default VNA port for IN2 ?

Re: Antenna analyser

Posted: Thu May 17, 2018 11:54 am
by pavel
sq3rx wrote:
Thu May 17, 2018 11:48 am
I am wondering is it safe to use it with baypass.
It should be safe if you set Level to -12 or -18 dB. Adding an attenuator to OUT1 could be also a solution.

Re: Antenna analyser

Posted: Sat Oct 06, 2018 9:19 am
by narrowstats
DeGaCo wrote:
Wed Apr 29, 2015 6:46 am
You need a directional coupler to get the reflected power than you can measure the reflection coefficent and calculate the VSWR. In this frequency range up to 30MHz I am not sure that a calibration is necessary. It is dependet on the quality of the coupler.
The problem with coupler is the limited bandwith. A transformator will cover the range 1MHz - 30MHz.

For a vector network analyser look at

You need two switch, two power splitter and two directional coupler. Because the RP has only two inputs the second switch will connect successive the signals to the input ports. To compensate the influence of the components a calibration will be necessary.

Thanks for the link.

Re: Antenna analyser

Posted: Sat Oct 20, 2018 7:30 am
by sq3rx
Sorry for trivial question, but I am not an expert in vna measurment...
Is it possible to measure insertion loss of antenna switch using RP VNA ? How should I connect antenna switch ?
Thanks for any advice

Re: Antenna analyser

Posted: Tue Oct 30, 2018 9:39 pm
by dk5hh
Hello list,
as I know, the VNAcode at the moment is designed as a 1-port measurement. -- From my point of view this is a a solid pythonic code. An excellent work by Pavel!

But it can be extended for two port measurement, if someone will take the opportunity to add this function to the code.

A cable 1-port return loss measurement opens the view on the cable losses (through- measurements).

cable loss := return loss / 2

may be, this helps for now!
Michael, DK5HH

Re: Antenna analyser

Posted: Thu Nov 01, 2018 11:53 am
by sq3rx
Hi Michael,
Thanks for explanation. I think it could be great addition to VNA software.
On github there is currently active topic "Use the VNA app for output power measurement not just".
https://github.com/pavel-demin/red-pita ... issues/772
I think it is quite similar to your idea. Isn't it ?
Maybe you can check this one and add your comment ?
73! Mek SQ3RX