miniVNA unter Linux - Erledigt

Zitat von dl1byt

Hallo OM‘s,

ich besitze seit Jahren einen miniVNA. Nach dem Kauf habe ich das Gerät unter Win7 installiert und benutzt. Überwiegend für Antennen-Messungen.

Seit ein paar Jahren bin ich auf Linux umgestiegen. Neulich wollte ich den Analyser benutzen, aber das Programm unter Win7 hatte ich nicht mehr.

So habe ich gesucht und gefunden ein Programm – vnaJ 3.4.8, womit unter Linux mein miniVNA nutzen kann.

Nachdem alles unter Linux lief, habe ich erst mal die Kalibrierung vorgenommen. Die Frequenz-Kalibrierung hat geklappt. Beim „erzeugen“ von

Reflexions-Kalibrierung erhalte ich keine richtige Kurve im ersten Fenster „Einlesen offen“ und das Button unter dem nächsten Fenster

„Einlesen Kurzschluss“ wird nicht aktiviert (siehe Bildschirm-Foto).

- Ist irgend eine Einstellung falsch?

- Funktioniert überhaupt der miniVNA mit vnaJ 3.4.8?

- ist vll. der miniVNA defekt? - Wie kann man das feststellen?

Nach langer Such im Netz habe ich auf diese Fragen keine Antworten/Infos gefunden.

Kann mir Jemand helfen?

Für Eure Hilfe danke ich im voraus.

73 de Csaba

Alles anzeigen

Hallo Csaba,

ich möchte sagen "vnaJ x.x.x" ist die richtige Software für die miniVNA- (Pro, Tiny) Serie. Besitze selbst den miniVNA Pro und hier läuft seit einem Jahr Ubuntu 20.04. Nutze aber z.Z. den VNA eher mobil mit der Android App "Blue VNA" - dort lässt sich auch kalibrieren. Vielleicht nützt Dir das etwas, einfach um zu Schauen, ob Dein Gerät damit funktioniert?! Wie man es dann unter Linux installiert, würde mich auch interessieren. Auf der Webseite von DL2SBA findet sich eine erste Hilfestellung, vielleicht kennst Du es?

P.S.: Ich hoffe das kein Defekt vorliegt! Erinnere mich aber, das die miniVNA empfindlich gegen elektrost. Aufladung wären, was vermutl. mal schnell gehen kann, wenn man ihn an eine passable Antenne anklemmt. Es gab dazu auch eine Anleitung (mittels spezieller Diode am Eingang?), um dies zu entschärfen.

Beste Grüße, Ingo, DO4ISL.

Hallo Csaba,

Bei mir läuft der MiniVNA unter vnaJ 3.4.6. problemlos. An der Software liegt es sicher nicht, die ist OK.

73 Heinz

Hallo Csaba,

Dankeschön für Deine Tipps fürs Installieren unter Linux! Sobald ich etwas Zeit finde will ich es versuchen!

Ich fand gerade ein paar archivierte Emails aus der damaligen Yahoo-Gruppe vom VNA wieder - vielleicht ist es von Interesse. Es handelt von der Fehlersuche, Reparatur aber auch dem Einbau entsprechender Schutzdioden am Eingang. Es soll wohl Geräte gegeben haben, wo auf der Platine eine Bestückung vorgesehen war, aber aus irgendeinem Grund nicht vorhanden waren.

Beste Grüße Ingo, DO4ISL.

Angefügter Text:

Hi Bill,

Just to let you know that you are getting out on the forum OK.

I have been watching the odd bit of traffic on the analysers and filing for reference. Your problem was of interest to me as I too have a Mini VNA Tiny, but to date works OK.

ESD is a problem and even top of the line professional equipment suffers from ESD as I have experienced within my professional workplace. So you are not alone with the problem.

Anyway very good to hear you have fixed your problem OK. Thanks for the update.

73, *******

On 10/01/2016 1:40 PM, Bill *******@gmail.com [analyzer_iw3hev] wrote:

>

>

> I'm not sure if this Yahoo group is even working on my end as I have not received any traffic at all... In the event that it is working, here is an update on my VNA Tiny. After troubleshooting with my scope, I replaced the ADG918 closest to the DUT port and the Tiny is back working like it used to be. I then added ESD7951S diodes to both ports to hopefully avoid ESD damage to the front end in the future.

> -Bill

>

> From: Bill

> Sent: Wednesday, December 30, 2015 1:32PM

> To: Analyzer Iw3hev

> Cc:

> Subject: Mini VNA Tiny Electrostatic Discharge Repair

>

>> Hello,

>>

>> First time with this group so I apologize if something similar has already been discussed...

>>

>> Has anyone repaired their Mini VNA Tiny after a possible electrostatic discharge into the DUT port?

>>

>> I'm normally very careful about ESD as I live in a dry climate. While working on an indoor antenna, the Mini VNA Tiny quit reading properly (SWR very close to 1:1 and Xs read +/- 25 across the entire sweep of 1-50 MHz). After checking my set up, the only reason I can think of is an ESD event. I re-soldered the DUT and DET port pins as they had dry solder joints but this did not help. After re-calibration the VNA is sort of working but has some anomalies and certainly not like it used to be. The Mini VNA Tiny appears to be wounded at best... I think I may have damaged one of the ADG918 switches in the front end but not completely sure... These little guys are mounted on thermal pads so they should be fun to try and remove without damaging the board... Is there any way to compare the calibration data before and after the event to help narrow down the problem?

>>

>> I see there are some pads for ESD diodes on the RF ports but they are not populated for some reason... Any suggested ones to use? I can only find 0402 (1005 metric) size ESD zeners that have capacitances below 1pF and fairly low clamp voltages... I don't do much work above 1GHz, so if I loose some bandwidth, it is a willing trade for a more robust front end. I'm looking at the MCC ESDSLC5V0D9B and the On Semi ESD7951S in the SOD-923 package as they are the biggest package I can find to hand solder...

>>

>> Thanks in advance!

>> -Bill

Und weiter:

Thank you for the Reply's Ben (***) and Ron (***), I was not sure I was getting out!

If it is of use to anyone else with a VNA Tiny, this is how I went about locating the problem with mine. I would have used reference designators but alas there are none on the board!

A diagram that I found to be very helpful was found here:

http://www.mikrocontroller.net/topic/351273

http://www.mikrocontroller.net…243812/vna_scm_col_v3.jpg

Scroll down the page a bit and look for a posting on 2015-01-11. It is just a block diagram but it was very useful in finding my way around the board for trouble-shooting...

O-Scope measurements made with damaged unit:

1) Set VNAJ for 1-5 MHz Reflection sweep in Freerun mode. DUT and DET ports open/unterminated.

2) RF out on DUT port 1.04Vpp sinewave with 0Vdc offset, sine undistorted.

3) RF out of DUT 2-resistor attenuator (near transformer) 0.46Vpp with 0Vdc offset, sine undistorted.

4) RF in to DUT ADG918 (pin 5) 0.46Vpp with 1.04Vdc offset, sine undistorted.

5) RF out of DUT ADG918 (pin 4) 0.15Vpp with 1.00Vdc offset, sine clipped on top

6) RF in to DET ADG918 (pin 5) 0.15Vpp with 0Vdc offset, sine clipped on top

7) RF out of DET ADG918 (pin 4) 0.15Vpp with 0Vdc offset, sine clipped on top

ADG918 Vdd (pin 1) 2.78Vdc on both switches (appears normal)

O-scope measurements after replacement of DUT ADG918

4) RF in to DUT ADG918 (pin 5) 0.31Vpp with 0.07Vdc offset, sine undistorted.

5) RF out of DUT ADG918 (pin 4) 0.30Vpp with 0.07Vdc offset, sine undistorted.

6) RF in to DET ADG918 (pin 5) 0.30Vpp with 0.07Vdc offset, sine undistorted.

7) RF out of DET ADG918 (pin 4) 0.29Vpp with 0.07Vdc offset, sine undistorted.

I added the ESD7951S (bi-directional TVS diodes) using two of the 3-terminal unpopulated pads near the DUT and DET ports. I'm sure a TVS of some sort was intended to go in these two places but not sure what device was in mind. Anyways after calibration I did not see any ill effects of adding the ESD7951S diodes at least up to 1 GHz where I am most interested. It would have been nice to find some with lower clamp voltages in a hand solderable package but hopefully these will help limit ESD damage should it occur in the future!

As for replacing the ADG918, I tried to use a hot iron on the tiny package body but the ground plane sucked too much heat to allow the part to release. I grabbed my old trusty hot air gun and the part came off easily. I soldered the part back on by hand including the ground pad underneath the part. After soldering, the pin alignment was off by about 10mils so I re-fluxed the part and used the hot air gun again and it re-aligned itself perfectly. I have a little USB microscope I use to inspect these tiny little parts as even with 6X magnification, I could not see well enough. I would recommend using a hot air and solder paste on tiny repairs like this. The gun I used was a Ungar 6966C with a home made small nozzle. It is a bit big but got the job done quickly.

Parts used in the repair:

IC SWITCH SPDT 2:1 MUX (tiny package 8-LFCSP)

Analog Devices ADG918BCPZ, Digikey ADG918BCPZ-REEL7CT-ND $3.27 ea

TVS DIODE 5VWM 12.9VC SOD923 (really tiny package ~ 0402)

On Semi ESD7951ST5G, Digikey ESD7951ST5GOSCT-ND $0.41 ea

73's Bill ***

From: *** ***

Sent: Sunday, January 10, 2016 1:38AM

To: Analyzer Iw3hev

Cc:

Subject: Re: [analyzer_iw3hev] Re: Mini VNA Tiny Electrostatic Discharge Repair

>

>

> Hi Bill,

>

> Just to let you know that you are getting out on the forum OK.

>

> I have been watching the odd bit of traffic on the analysers and filing for reference. Your problem was of interest to me as I too have a Mini VNA Tiny, but to date works OK.

>

> ESD is a problem and even top of the line professional equipment suffers from ESD as I have experienced within my professional workplace. So you are not alone with the problem.

>

> Anyway very good to hear you have fixed your problem OK. Thanks for the update.

>

> 73, Ben ***

>

>

> On 10/01/2016 1:40 PM, Bill ***@gmail.com [analyzer_iw3hev] wrote:

>>

>>

>> I'm not sure if this Yahoo group is even working on my end as I have not received any traffic at all... In the event that it is working, here is an update on my VNA Tiny. After troubleshooting with my scope, I replaced the ADG918 closest to the DUT port and the Tiny is back working like it used to be. I then added ESD7951S diodes to both ports to hopefully avoid ESD damage to the front end in the future.

>> -Bill

>>

>> From: Bill

>> Sent: Wednesday, December 30, 2015 1:32PM

>> To: Analyzer Iw3hev

>> Cc:

>> Subject: Mini VNA Tiny Electrostatic Discharge Repair

>>

>>> Hello,

>>>

>>> First time with this group so I apologize if something similar has already been discussed...

>>>

>>> Has anyone repaired their Mini VNA Tiny after a possible electrostatic discharge into the DUT port?

>>>

>>> I'm normally very careful about ESD as I live in a dry climate. While working on an indoor antenna, the Mini VNA Tiny quit reading properly (SWR very close to 1:1 and Xs read +/- 25 across the entire sweep of 1-50 MHz). After checking my set up, the only reason I can think of is an ESD event. I re-soldered the DUT and DET port pins as they had dry solder joints but this did not help. After re-calibration the VNA is sort of working but has some anomalies and certainly not like it used to be. The Mini VNA Tiny appears to be wounded at best... I think I may have damaged one of the ADG918 switches in the front end but not completely sure... These little guys are mounted on thermal pads so they should be fun to try and remove without damaging the board... Is there any way to compare the calibration data before and after the event to help narrow down the problem?

>>>

>>> I see there are some pads for ESD diodes on the RF ports but they are not populated for some reason... Any suggested ones to use? I can only find 0402 (1005 metric) size ESD zeners that have capacitances below 1pF and fairly low clamp voltages... I don't do much work above 1GHz, so if I loose some bandwidth, it is a willing trade for a more robust front end. I'm looking at the MCC ESDSLC5V0D9B and the On Semi ESD7951S in the SOD-923 package as they are the biggest package I can find to hand solder...

>>>

>>> Thanks in advance!

>>> -Bill

Der miniVNA kann nur die einfache Kalibrierung. Steht so auch im DriverGuide dazu: https://download.dl2sba.com/vn…r/DriverGuide_miniVNA.pdf.

Kalibrierung speichern und gut ist.