Original NanoVNA a waste of money


Andy G4JNT
 

I bought one of the original NanoVNAs not long afte rthay came out, and initially it worked OK.  Put it away and hadn't used in for perhaps nearly a year.
When I came to use it today, obvs. the battery needed charging, but the touchscreen ignores most of my presses, and those it does interpret it gets wrong then goes into a huff
The manual slider doesn't respond
 
Don't think I'll ever get one again, no matter how much better the new ones are.   

Not sure whether to put a hammer through it or dismantle to see what's inside.
A hammer would be more satisfying.

Meanwhile, the job I wanted it for, the DG8SAQ did the job perfectly, with a much nicer display.  Just meant taking the laptop and the 'SAQ outside - so wasn't so convenient.


Virus-free. www.avg.com


geoffrey pike
 

Well there you go, i do the opposite and haven't switched my SAQ in over a year (i suppose when i do there will be aggro getting it going again)
But the SAA-2 really is way ahead in frequency perhaps not the best of software support however
I think the SAQ needs to extend a bit in frequency to make it attractive to new users
Just my 3ds worth
cheers
Geoff
GI0GDP



On Friday, 19 March 2021, 17:29:50 GMT, Andy G4JNT <andy.g4jnt@...> wrote:


I bought one of the original NanoVNAs not long afte rthay came out, and initially it worked OK.  Put it away and hadn't used in for perhaps nearly a year.
When I came to use it today, obvs. the battery needed charging, but the touchscreen ignores most of my presses, and those it does interpret it gets wrong then goes into a huff
The manual slider doesn't respond
 
Don't think I'll ever get one again, no matter how much better the new ones are.   

Not sure whether to put a hammer through it or dismantle to see what's inside.
A hammer would be more satisfying.

Meanwhile, the job I wanted it for, the DG8SAQ did the job perfectly, with a much nicer display.  Just meant taking the laptop and the 'SAQ outside - so wasn't so convenient.


Virus-free. www.avg.com


Andy G4JNT
 

Yes, agreed.   For higher frequencies I have several directional couplers for DC to 12GHz and use a synth + spec analyser as a makeshift scalar return loss measurement.   A PRN based  noise source and mixer gives a wideband signal for some applications



Virus-free. www.avg.com


On Fri, 19 Mar 2021 at 17:46, geoffrey pike via groups.io <gi0gdp=yahoo.co.uk@groups.io> wrote:
Well there you go, i do the opposite and haven't switched my SAQ in over a year (i suppose when i do there will be aggro getting it going again)
But the SAA-2 really is way ahead in frequency perhaps not the best of software support however
I think the SAQ needs to extend a bit in frequency to make it attractive to new users
Just my 3ds worth
cheers
Geoff
GI0GDP



On Friday, 19 March 2021, 17:29:50 GMT, Andy G4JNT <andy.g4jnt@...> wrote:


I bought one of the original NanoVNAs not long afte rthay came out, and initially it worked OK.  Put it away and hadn't used in for perhaps nearly a year.
When I came to use it today, obvs. the battery needed charging, but the touchscreen ignores most of my presses, and those it does interpret it gets wrong then goes into a huff
The manual slider doesn't respond
 
Don't think I'll ever get one again, no matter how much better the new ones are.   

Not sure whether to put a hammer through it or dismantle to see what's inside.
A hammer would be more satisfying.

Meanwhile, the job I wanted it for, the DG8SAQ did the job perfectly, with a much nicer display.  Just meant taking the laptop and the 'SAQ outside - so wasn't so convenient.


Virus-free. www.avg.com


Paul G4KZY
 

For higher frequencies, and to use with your directional couplers you could dig out your ADALM Pluto.

Alberto's SATSAGEN software is really very useful.

73,

Paul


geoffrey pike
 

Indeed it's a useful tool, but so far they are all a bit too slow to tune anything with but i agree Alberto has done
a fantastic job with the Pluto
Geoff
GI0GDP


On Saturday, 20 March 2021, 16:23:01 GMT, Paul G4KZY <paul.g4kzy@...> wrote:


For higher frequencies, and to use with your directional couplers you could dig out your ADALM Pluto.

Alberto's SATSAGEN software is really very useful.

73,

Paul


Andy G4JNT
 

Update.
I removed front ang back covers, and it started to - sort of - work.  The touch screen is a total failure, but I can drive it using the manual button thing.  replaced the covers and it stayed working.    SO I'm guessing an intermittent in a ribbon cable link on the touchscreen.
SO it has been saved from the sledgehammer for now.

Also took the opportunity to look inside, including lifting the covers over the RF portion. Pretty boring; three NE602 mixer chips, something that is obviously a soundcard type interface chip and one that is probably an Si family synth  - although the number was a bit meaningless.



On Sat, 20 Mar 2021 at 17:47, geoffrey pike via groups.io <gi0gdp=yahoo.co.uk@groups.io> wrote:
Indeed it's a useful tool, but so far they are all a bit too slow to tune anything with but i agree Alberto has done
a fantastic job with the Pluto
Geoff
GI0GDP


On Saturday, 20 March 2021, 16:23:01 GMT, Paul G4KZY <paul.g4kzy@...> wrote:


For higher frequencies, and to use with your directional couplers you could dig out your ADALM Pluto.

Alberto's SATSAGEN software is really very useful.

73,

Paul


Steve, G4VBD <stephen.mcadam56@...>
 

Hi Andy
Here is a YouTube video explaining how the nano vna works
https://www.youtube.com/watch?v=cU05VVFl0N0&t=1s
There are also a couple of programs to control the nano van from a pc, Nanovan saver is one I've used.

Hope this helps
Steve, g4vbd


Steve, G4VBD <stephen.mcadam56@...>
 


Nick
 

Andy

I also have an original 2.8" nanovna repackaged in a diecast box with N-type connectors and a bigger battery.

Suggest you charge the battery, install latest firmware and give yours a careful touch calibration before trashing it.

Be sure to use the correct firmware i.e. the -H version not the -H4.

https://github.com/hugen79/NanoVNA-H/releases
https://groups.io/g/nanovna-users/topics

HTH

Nick


G8DQX list
 

Andy,

the block diagram and circuit (schematic) diagram are at https://github.com/ttrftech/NanoVNA/blob/master/doc/nanovna-blockdiagram.png. What brings the machine alive, though, is the firmware, which has had considerable development over time.

There are occasional reports on the nanoVNA list (https://groups.io/g/nanovna-users) of touch screens failing due to cases fouling the surface. The usual solution seems to be to add washers or shims. One also has a vague recollection of solder splashes being a problem.

HTH, 73, Stay Safe,

Robin, G8DQX

On 21/03/2021 13:04, Andy G4JNT wrote:
Update.
I removed front ang back covers, and it started to - sort of - work.  The touch screen is a total failure, but I can drive it using the manual button thing.  replaced the covers and it stayed working.    SO I'm guessing an intermittent in a ribbon cable link on the touchscreen.
SO it has been saved from the sledgehammer for now.

Also took the opportunity to look inside, including lifting the covers over the RF portion. Pretty boring; three NE602 mixer chips, something that is obviously a soundcard type interface chip and one that is probably an Si family synth  - although the number was a bit meaningless.



Andy G4JNT
 

I've had a DG8SAQ VWNA for a long time, now, which in terms of performance, quality of software, display capability and user interface knocks spots off these Chinese things.   Its a really professional quality bit of kit and would normally be the only one I'd ever use.   In use, it's as nice to use as the HP ones I used to use at work - just doesn't go nearly as high in frequency :-(

But it needs a PC attached, so when out in the garden or up a mast (!) a small self contained one has more than a few advantages.

These Chinese Mini VNWAs are a blatant rip-off of the DG8SAQ, that uses exactly the same hardware, NE602/612 mixers that conveniently have a differential input so perfect for taking the output from a resistive bridge right down to DC.  



On Sun, 21 Mar 2021 at 16:27, G8DQX list <list@...> wrote:

Andy,

the block diagram and circuit (schematic) diagram are at https://github.com/ttrftech/NanoVNA/blob/master/doc/nanovna-blockdiagram.png. What brings the machine alive, though, is the firmware, which has had considerable development over time.

There are occasional reports on the nanoVNA list (https://groups.io/g/nanovna-users) of touch screens failing due to cases fouling the surface. The usual solution seems to be to add washers or shims. One also has a vague recollection of solder splashes being a problem.

HTH, 73, Stay Safe,

Robin, G8DQX

On 21/03/2021 13:04, Andy G4JNT wrote:
Update.
I removed front ang back covers, and it started to - sort of - work.  The touch screen is a total failure, but I can drive it using the manual button thing.  replaced the covers and it stayed working.    SO I'm guessing an intermittent in a ribbon cable link on the touchscreen.
SO it has been saved from the sledgehammer for now.

Also took the opportunity to look inside, including lifting the covers over the RF portion. Pretty boring; three NE602 mixer chips, something that is obviously a soundcard type interface chip and one that is probably an Si family synth  - although the number was a bit meaningless.



geoffrey pike
 

THe SAA-2 is very different
Geoff
GI0GDP

On Sunday, 21 March 2021, 16:41:35 GMT, Andy G4JNT <andy.g4jnt@...> wrote:


I've had a DG8SAQ VWNA for a long time, now, which in terms of performance, quality of software, display capability and user interface knocks spots off these Chinese things.   Its a really professional quality bit of kit and would normally be the only one I'd ever use.   In use, it's as nice to use as the HP ones I used to use at work - just doesn't go nearly as high in frequency :-(

But it needs a PC attached, so when out in the garden or up a mast (!) a small self contained one has more than a few advantages.

These Chinese Mini VNWAs are a blatant rip-off of the DG8SAQ, that uses exactly the same hardware, NE602/612 mixers that conveniently have a differential input so perfect for taking the output from a resistive bridge right down to DC.  



On Sun, 21 Mar 2021 at 16:27, G8DQX list <list@...> wrote:

Andy,

the block diagram and circuit (schematic) diagram are at https://github.com/ttrftech/NanoVNA/blob/master/doc/nanovna-blockdiagram.png. What brings the machine alive, though, is the firmware, which has had considerable development over time.

There are occasional reports on the nanoVNA list (https://groups.io/g/nanovna-users) of touch screens failing due to cases fouling the surface. The usual solution seems to be to add washers or shims. One also has a vague recollection of solder splashes being a problem.

HTH, 73, Stay Safe,

Robin, G8DQX

On 21/03/2021 13:04, Andy G4JNT wrote:
Update.
I removed front ang back covers, and it started to - sort of - work.  The touch screen is a total failure, but I can drive it using the manual button thing.  replaced the covers and it stayed working.    SO I'm guessing an intermittent in a ribbon cable link on the touchscreen.
SO it has been saved from the sledgehammer for now.

Also took the opportunity to look inside, including lifting the covers over the RF portion. Pretty boring; three NE602 mixer chips, something that is obviously a soundcard type interface chip and one that is probably an Si family synth  - although the number was a bit meaningless.