Re: Basics to look at when buying nanovna
A ham supply shop, R&L, was recently advertising the H4 for $59.95 and a buddy got one early this week. Today they say out of stock. But now they also show the 2.8 inch model for $49.95.
Link:
Doug
|
Re: Calibration connectors
|
Re: Calibration connectors
The material is silver-plated brass, directly nanovna "hangs" in the air, as it were, but has adjustment with nuts for stiffness.
It does not have a very rigid attachment to the base.
|
Re: QUALITY OF SUPPLIED CAL STANDARDS
No problem, Terry. I'll be glad to evaluate them against the HP 'gold
standards'.
BTW: Welcome back from Florida!
Dave
<>
Virus-free.
www.avast.com
<>
<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
toggle quoted message
Show quoted text
On Fri, Mar 6, 2020 at 3:19 AM Terry Bullett <tbullett@...> wrote: Dave,
I have a couple of sets of SMA SOL standards from Amazon. Would you be
willing to test them against your standards? I think I recall nanoVNA
Viewer allowing for imperfect standards using RLC values. The HDSDR VNA
software for my Hermes board (now lost in Puerto Rico) computed equivalent
RLC models for the loads. I ignored these below 30 MHz.
Terry
On 2/21/20 5:43 PM, David Eckhardt wrote:
This afternoon I decided to look at the supplied cal standards supplied
with the original small format NANOVNA and the NANOVNA-F. These are the
two I presently own. The standards were compared to HP 'precision' SMA cal
standards included in the HP cal kit 85033. I used those from the HP cal
kit to calibrate the HP 8753C with the HP 85047A S-Parameter Test Set.
Once this was done, I took a look at the supplied cal standards from each
NANO unit. The frequency sweep covers 300 kHz through 1.5 GHz. Markers as
placed at 1 MHz, 750 MHz, and 1.5 GHz. The values measured are displayed
on each image. I'll attach the Smith Chart measurements of each supplied
standard as I measured them after cal. The label referring to each image
should be self explanatory.
Draw your own conclusions.
--
*Dave - W?LEV *
*Just Let Darwin Work*
*Just Think*
--
*Dave - W?LEV*
*Just Let Darwin Work*
*Just Think*
|
Re: How can I use a nanoVNA to test an active antenna
I should add there is significant info on using the vna to accomplish antenna measurements. Just google on those key words " antenna measurement using a vna "... Tek, Keysight, others have extensive docs, app notes and videos!
Alan
|
Re: How can I use a nanoVNA to test an active antenna
Hi Jean.
The active antenna is a one port just like a Passive, however with an active element present. So you need to limit the input power if you want to probe the port where the antenna element is connected. These vna devices provide about -12 dBm. Attenuation of 20 dB may be required when probing the antenna port while no attenuation may be required down at the " pit " where your receiver is located. I assume your bias tee for the active antenna is providing a dc block, so no issue with harm to the vna. If a one port measure at the output of the antenna then CH0 will provide return loss. Otherwise you could remove the passive part of the active antenna and sweep a 2 port response to look at the amplifier, follower, filters etc...
Alan
|
Re: Ceramic filter measurement
On Wed, Mar 4, 2020 at 10:55 PM, <sj@...> wrote: Yes, and completely agree with your comments on layout and parasitic C. But it is 10.7 MHz, too. The Murata group delay curves, being the first derivative of phase, should reflect imaginary effects, as you need real and imaginary for phase. Those side saddle hump changes for the group delay curves point out the group delay changes nicely. Some vintage Yamaha and Sansui FM tuners have adjustment pots for each ceramic filter to allow tweaking for minimum distortion. Only on the $$$ models, though. BTW, for the wide Murata GDT types (SFE10.7MX-A), which appear to have a Bessel type amplitude response, the group delay is flat as a pancake in the passband. But they have horrible selectivity, and high insertion loss.
Be aware that the curves in the muRata datasheet does only show pass band vs
real load. Imaginary loads like parasitic capacitance will also impact.
|
On Thu, Mar 5, 2020 at 11:41 AM, Roger Need wrote:
The SAA-2 (NanoVNA V2) has a 2.8" screen which is disappointing...
================================================================
Roger,
A larger screen size would have been more desirable but the price point Gabriel's client was shooting for looks like didn't make it happen. Gabriel did say her design would accept either a 2.8" or 3.2" display, so you could swap out displays yourself, or wait for the client to offer a premium model with 3.2" display at a higher price.
You could also ignore the display and treat the SAA-2 like a miniVNA or VNWA, which are USB only, and you still have a heck of a bargain.
- Herb
|
Re: Anyone had news from Maggie King?
Received a working and well packed VNA yesterday. Well done!
Cheers,
Kaj OH6EH
toggle quoted message
Show quoted text
On Tue, 25 Feb 2020 at 10:26, Kaj Wiik <kaj.wiik@...> wrote: I got a friendly email today containing a tracking number, order was
placed on Jan 21
.
They are doing a very good job considering the circumstances!
Cheers,
Kaj OH6EH
On Sat, 22 Feb 2020 at 06:28, JimR <WO4X@...> wrote:
I got a SMS text from DHL that my delivery ETA is Tuesday, and that a
signature is required.
|
Hi Gabriel,
It would be great if you could find out from the seller/manufacturer is they would be willing to accept PayPal payments via email, the same way that Maggie King did for Hugen's devices.
I'd love to get one of these if that method is available.
Thanks,Larry
toggle quoted message
Show quoted text
On Thursday, March 5, 2020, 10:39:22 a.m. GMT-5, Gabriel Tenma White <owowowowo123@...> wrote:
Here's the link to the taobao listing:
Although if you are outside China I would wait for the tindie listing; it's supposed to be awaiting approval now.
|
|
|
The SAA-2 (NanoVNA V2) has a 2.8" screen which is disappointing...
Roger
|
Re: Basics to look at when buying nanovna
hi Dave,
I am looking where and what to buy. One of the VNA's is for my friend at work, the other for myself.
We would both opt for the 1.5 GHz version despite the low dynamic range there. Probably use some SMA to N pigtails and built it in a cabinet of some sort. (so N type cal kit is needed)
There is a benchtop and some portable VNA's at work, but I have to borrow them in time etc. and they're never around on Sunday if you want to try something.
Did not know they came in different screen sizes? Well, I'm twenty years younger, but bigger is also for me better in this case :-) .
But it seems you can connect them to a PC which makes life easier :-)
br Jan PA3GSV
|
Is this an optical illusion or is this any tiny lcd on the V2?
If so, Hugen, get busy and make us a 4" version. ;-)
Two steps forward, one step back.
73
Glen K4KV
|
I think S11 noise floor refers to the floor of the return loss that can
be displayed; at this point the system noise overwhelms the output of
the directional coupler or bridge. Basically, it's the limit to the dB
of directivity you can get after calibration.
John
----
toggle quoted message
Show quoted text
On 3/5/20 2:04 PM, Dragan Milivojevic wrote: Can someone explain what does "S11 noise floor" mean exactly?
From the marketing perspective the product is a bit confusing. No battery
and no case but with a screen.
Makes no sense. Also no accessories. It would make more sense to ditch the
screen and add a proper case
like the rest of the "desktop" VNA or copy the current approach
(it is beyond me why most people want a tiny screen that has no purpose in
90% of use cases).
Anyway I think that they are wasting their competitive advantage (higher
performance) with lousy execution.
On Thu, 5 Mar 2020 at 18:59, <erik@...> wrote:
Spec as on taobao:
NanoVNA V2
3GHz second-generation NanoVNA vector network analyzer, based on OwOComm's
SAA-2 design, greatly upgraded performance.
specification:
Measurement frequency range: 50kHz-3GHz
System dynamic range (after calibration): 70dB (50k to 1.5GHz); 60dB (to
3GHz)
S11 noise floor (after calibration): -50dB (to 1.5GHz); -40dB (to 3GHz)
Scanning rate: 100 points / second
Number of scanning points (on the device screen): adjustable, maximum 201
points
Number of calibration points (maximum number of USB scanning points): 1024
points
Power: USB, 400mA
RF port: SMA (not RP-SMA!)
USB interface: Micro USB
Display screen: 2.8-inch TFT (320 x 240)
Battery: without battery , can be equipped with 1000-1800 mAh 3.6V / 3.7V
lithium battery, 6 * 40 * 60 mm, XH 2.54 connector
Show traces: 4, Marks: 4, Settings saved: 5
Computer software compatible: Linux, Windows (7 and above)
Operation Introduction
Tap anywhere on the screen to open the menu
Setting the frequency range with the STIMULUS menu
Calibration using the CAL> CALIBRATE menu
Price is 350Yan which is at current exchange rate 45Euro or 50$
No housing
--
NanoVNA Wiki: /g/nanovna-users/wiki/home
NanoVNA Files: /g/nanovna-users/files
Erik, PD0EK
|
Can someone explain what does "S11 noise floor" mean exactly?
From the marketing perspective the product is a bit confusing. No battery
and no case but with a screen.
Makes no sense. Also no accessories. It would make more sense to ditch the
screen and add a proper case
like the rest of the "desktop" VNA or copy the current approach
(it is beyond me why most people want a tiny screen that has no purpose in
90% of use cases).
Anyway I think that they are wasting their competitive advantage (higher
performance) with lousy execution.
toggle quoted message
Show quoted text
On Thu, 5 Mar 2020 at 18:59, <erik@...> wrote: Spec as on taobao:
NanoVNA V2
3GHz second-generation NanoVNA vector network analyzer, based on OwOComm's
SAA-2 design, greatly upgraded performance.
specification:
Measurement frequency range: 50kHz-3GHz
System dynamic range (after calibration): 70dB (50k to 1.5GHz); 60dB (to
3GHz)
S11 noise floor (after calibration): -50dB (to 1.5GHz); -40dB (to 3GHz)
Scanning rate: 100 points / second
Number of scanning points (on the device screen): adjustable, maximum 201
points
Number of calibration points (maximum number of USB scanning points): 1024
points
Power: USB, 400mA
RF port: SMA (not RP-SMA!)
USB interface: Micro USB
Display screen: 2.8-inch TFT (320 x 240)
Battery: without battery , can be equipped with 1000-1800 mAh 3.6V / 3.7V
lithium battery, 6 * 40 * 60 mm, XH 2.54 connector
Show traces: 4, Marks: 4, Settings saved: 5
Computer software compatible: Linux, Windows (7 and above)
Operation Introduction
Tap anywhere on the screen to open the menu
Setting the frequency range with the STIMULUS menu
Calibration using the CAL> CALIBRATE menu
Price is 350Yan which is at current exchange rate 45Euro or 50$
No housing
--
NanoVNA Wiki: /g/nanovna-users/wiki/home
NanoVNA Files: /g/nanovna-users/files
Erik, PD0EK
|
Re: Basics to look at when buying nanovna
On Thu, Mar 5, 2020 at 09:02 AM, David Eckhardt wrote:
The -H4 covers up to 1.5 GHz where the -F covers to 1 GHz. The original covers to 900 MHz (which I also have). All are improvements over the initially offered units.
====================================================
David,
I think you need to upgrade your NanoVNA-F firmware to FW v0.1.1 as it extends the frequency coverage to 10 kHz - 1.5 GHz. I agree that that either the -H4 or -F models would be a better choices over the 2.8" NanoVNA-H.
- Herb
|
Here is a pdf with the translation of the Taobao Web site listing for the SAA-2
|
Re: Calibration connectors
Aleksander, great idea and it looks nice!
What's that base plate material? Do you notice any flexing of the SMA/Nano interface?
--
I_B_Nbridgema
|
Spec as on taobao: NanoVNA V2 3GHz second-generation NanoVNA vector network analyzer, based on OwOComm's SAA-2 design, greatly upgraded performance. specification: Measurement frequency range: 50kHz-3GHz System dynamic range (after calibration): 70dB (50k to 1.5GHz); 60dB (to 3GHz) S11 noise floor (after calibration): -50dB (to 1.5GHz); -40dB (to 3GHz) Scanning rate: 100 points / second Number of scanning points (on the device screen): adjustable, maximum 201 points Number of calibration points (maximum number of USB scanning points): 1024 points Power: USB, 400mA RF port: SMA (not RP-SMA!) USB interface: Micro USB Display screen: 2.8-inch TFT (320 x 240) Battery: without battery , can be equipped with 1000-1800 mAh 3.6V / 3.7V lithium battery, 6 * 40 * 60 mm, XH 2.54 connector Show traces: 4, Marks: 4, Settings saved: 5 Computer software compatible: Linux, Windows (7 and above) Operation Introduction Tap anywhere on the screen to open the menu Setting the frequency range with the STIMULUS menu Calibration using the CAL> CALIBRATE menu Price is 350Yan which is at current exchange rate 45Euro or 50$ No housing -- NanoVNA Wiki: /g/nanovna-users/wiki/homeNanoVNA Files: /g/nanovna-users/filesErik, PD0EK
|
Aleksander Shalygin
Roger Need
Jan PA3GSV
Nbridgema
