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Hi folks,

I need help to know if my newly bought (few months ago) VNA V2 Plus 4 from Tindie is good unit or not. When any antenna connected it do not draw the SWR graph. I am sure it is a good unit and as a new user I am doing something wrong.

Initially I just turned on the device and checked if the menus are working and device respond to touch screen and found OK. For a month and a half was busy and did not have time to play with the device. From last 4 to 6 weeks, I gone through the docs available in the Wiki written by Martin Savacoi (9A2JK) and the one found online written particularly for this unit by Bill Ruggirello (NC4BR). I still think I am doing something wrong that after the calibration done as described below, I am still doing something wrong that when an antenna is connected it do not display SWR graph.

Here what I did for the cabliberation.

-Turn on the unit.
-Display > Channel: selected Ch0 Reflect
-Frequency set = 100Mhz ~ 900Mhz.
-Display > Trace > 0 is ON.
1, 2, 3 are OFF and grayed out.
-Display > Format : SWR
-Display > Scale > Scale/Div = .25 X1
-Calibrate > Calibrate :
Connected first the "OPEN" standard on Ch0, then pressed Open. Had a check mark and show on the left hand side "O"
Then connected "SHORT" standard on Ch0, pressed SHORT. Had a check mark and show on the left hand side "S"
Then connected "LOAD" standard on Ch0 , pressed LOAD. Had a check mark and show on the left hand side "L"
Then connected nothing on Ch0 , pressed THRU. Had a check mark and show on the left hand side "T"

I saved the calibration in slot 0 (Zero).
Set the range on memory 4 for 144 MHz to 148MHz (and other ranges in other slots).
I connected my Diamond HT antenna "SRH230" and the VNA do not show any graphs.

Attached are the pictures I have taken. Please open the pictures and I placed some handwritten notes on them. What I am doing wrong? Anyone can help.
Thank you,
Sohail, VE3ITU.

Then connected nothing on Ch0 , pressed THRU. Had a check mark and show on the left hand side "T"

For THRU calibration Ch0 must be connected to Ch1.

Suggest you read this excellent document...

/g/nanovna-users/files/Absolute%20Beginner%20Guide%20to%20The%20NanoVNA/Absolute_Beginner_Guide_NanoVNA_v1_6.pdf

HTH

Nick

Check your scale. Upper left shows swr of over 7 ( or something like that. Hard to read on my phone).

Hi Nick,
Thank you for your reply. I already gone through that user guide that you are referring to. As you see I mentioned in my post above but obviously missing some important steps. I got some suggestion from another group. Will post the findings.

Sohail VE3ITU.

Hi Ron,
Thank you for the tip. Someone also suggested same as you said. But there are few other things and until I do not go through them its not going to show the graph properly. I tried changing the scale from 0.25 to 2 with no success. Someone on another group also suggested extra few things. Will do and post the results here.

Sohail VE3ITU.

Hi folks,

It's being while I didn't posted my repeated testing results under this message thread. As my device is NanoVNA V2 Plus4 so ended up posting few extra posts in other groups as some members suggested few things here and there.

I even upgraded 2 new firmwares with no success. The results were same as what you see the pictures I posted earlier in my above post.

I contacted the manufacturer, the Hcxqgroup and the asked me to run the tests and share the pictures, same what I shared here in this message thread.

They told me the device is defective. Sending me a replacement.

Thank you for those who responded here and helped me.

Sohail ve3itu