On Wed, Aug 23, 2023 at 10:07 AM, Geoff Peters - AB6BT wrote:
How does calibration affect the Thansform measurement?
You need to be calibrated over the frequency range that you select. However there is calibration interpolation used on some NanoVNA's, like the -H and -H4, so you can arrow the frequency range if you want to measure longer cables. However for best accuracy calibrate over the frequency range that accommodates your cable length. The lower frequency should be kept at 50 kHz and the upper frequency limit , number of sample points and velocity factor entered will determine the maximum length that can be measured.
If I set the stimulus start and stop to 50KHz and 1.5GHz the transform maximum
length is shown as 19.36m. If I set the sweep to 401 points what resolution
and accuracy can I expect, provided that I have the VF entered correctly.
1936mm/401 equals just over 4.8mm.
Your calculation is correct. However you won't be accurate to 4.8 mm becasue the velocity factor you enter (in percent) is only in steps of 1 so this is the limiting factor. Roger
|
Yes, that's what I do, not a problem...
toggle quoted message
Show quoted text
On 8/23/2023 12:59 PM, Clyde Spencer wrote: Make sure you enter the VF as a percentage not a decimal value. EXAMPLE 60
not .60
*Clyde K. Spencer*
On Wed, Aug 23, 2023 at 1:08?PM Geoff Peters - AB6BT <AB6BT@...>
wrote:
I have a couple questions regarding using the Transform function to
measure length of a cable.
How does calibration affect the Thansform measurement?
If I set the stimulus start and stop to 50KHz and 1.5GHz the transform
maximum length is shown as 19.36m. If I set the sweep to 401 points what
resolution and accuracy can I expect, provided that I have the VF entered
correctly.
1936mm/401 equals just over 4.8mm.
Thanks,
Geoff -- AB6BT
|
Make sure you enter the VF as a percentage not a decimal value. EXAMPLE 60 not .60 *Clyde K. Spencer* On Wed, Aug 23, 2023 at 1:08?PM Geoff Peters - AB6BT <AB6BT@...> wrote: I have a couple questions regarding using the Transform function to
measure length of a cable.
How does calibration affect the Thansform measurement?
If I set the stimulus start and stop to 50KHz and 1.5GHz the transform
maximum length is shown as 19.36m. If I set the sweep to 401 points what
resolution and accuracy can I expect, provided that I have the VF entered
correctly.
1936mm/401 equals just over 4.8mm.
Thanks,
Geoff -- AB6BT
|
I have a couple questions regarding using the Transform function to measure length of a cable.
How does calibration affect the Thansform measurement?
If I set the stimulus start and stop to 50KHz and 1.5GHz the transform maximum length is shown as 19.36m. If I set the sweep to 401 points what resolution and accuracy can I expect, provided that I have the VF entered correctly.
1936mm/401 equals just over 4.8mm.
Thanks,
Geoff -- AB6BT
|
Re: some Nano VNA SAVER 40m antenna graphs
That will be a very interesting comparison test!
I hope you publish all the details and measurements.
(Great choices of antennas, too. My full-wave horizontal loop is terrific.)
--
Doug, K8RFT
|
some Nano VNA SAVER 40m antenna graphs
Getting Ready for the new
**** MidAtlantic 40m NBEMS net ****
testing: Saturday and Sunday 10 AM EDT on 7068 kHz (vfo)
coverage over a 300 mile radius from Philadelphia
THOR 22 check in
THOR 56 traffic (new alpha mode: w1hkj.com/alpha)
Hope to have the net begin by October 7/8 2023
Need 5-8 net control ops from the MidAtlantic region
I now have three 40m antennas to compare prop paths
1) Traditional Inv V dipole, center fed with 1:1 BALUN 66 ft
2) Full one-wave horizontal loop (140 ft)
3) 34 ft alum tubing Vertical (lashed to a tall tree) with two above gnd 30 ft radials
and matching coil at base (like an inverted T )
I had to mess a bit with the length of vertical to get it resonant where I wanted it.
de k3eui barry Aug 22 2023
|
Nuno, I was pretty happy with my NanoVNA-F V2 until it randomly died on me. It lasted nearly 2 years though and had zero issues with it before it died. I took a gamble and purchased the SV4401A because I wanted more accuracy (and range) out of a portable VNA.
The SV4401A is *not* light nor compact. So far, I'm very happy with my unit. The firmware is fairly stable, so I have no complaints.
I purchased mine from E-Bay from a China seller. I got mine in about 8 days which was pretty quick.
-Nick, k7cj
|
I forgot to add this link
|
On 8/21/23 8:45 AM, Leif M wrote: Likewise. I would recommend V2 Plus4 or V2 Plus4 PRO from an official store. There are several other version but I like V2 Plus4. Today perhaps PRO version. Battery lasts a long time and results are good enough. If the tool works at 4GHZ, it will surely be good at 50MHz and 1GHz. I am not totally satisfied with PC software. It is usable but not well finished.
Then there is the VNA6000.
The only potential downside to the V2 is that they are more sensitive to ESD, because they have a monolithic RF switch at the input.
|
Likewise. I would recommend V2 Plus4 or V2 Plus4 PRO from an official store. There are several other version but I like V2 Plus4. Today perhaps PRO version. Battery lasts a long time and results are good enough. If the tool works at 4GHZ, it will surely be good at 50MHz and 1GHz. I am not totally satisfied with PC software. It is usable but not well finished.
Then there is the VNA6000.
|
i have finaly got my pc to tato the vna,ready to load fw,can anyone tell me what FW has the biggest fonts with the most save slots,thanks.
|
Is not easy as you said. It needs to be new design and higher speed components. See link:
FC
|
Hi,i tried using teraterm on my vna,it connected ok using com 19,i ran learconfig 1234,now it wont connect to my pc,terraterm only sees com 1 not 10,the stm32 bootloader tab in device manager says cant find driver,i assume this is my issue,its like my win 10 64bit pc cant see my nanovna anymore,any ideas how i can fix it?,or where to find the drivers?,cheers+73.
|
Re: hi how so i run console comands on my vna,its the first version.
Connect it via USB and open the serial port in a terminal program, bitrate etc. is not relevant. Type e.g. "help" to see the available commands.
|
hi how so i run console comands on my vna,its the first version.
Do i need to connect it to my pc,if so how,i see no guides for doing it.thanks+73
|
I have two other nanoVNAs but I find myself reaching for the SAA-2N most often. The calibration kit and cables provided are of good quality and have held up (so far). For higher frequencies I have a LibreVNA but it is in a different class of instruments and an order of magnitude more costly.
73, Don N2VGU
|
many of the models can be easy improved (lower noise above 2 ghz with just some decoupling caps added) .. i bet yours is similar :-)
dg9bfc sigi
ps welcome in the group of fancy smith diagramms , antenna tests and other nice things your can test with the nanos
Am 19.08.2023 um 16:31 schrieb fcusa@...:
toggle quoted message
Show quoted text
Hi, I just got my SAA-V2 clone 3.2" "black and gold" (info link ) from ebay.
I'm very happy with it. Cost less then $100 and cover up to 4GHz can also measure my wifi and cellphone gears.
Have a good day.
FC
|
I have the H H4 SAA2N and the F models and use them in different applications. If you intend to use it outdoors I strongly recommend the F model with the pushbuttons. It has the brightest display which is necessary outdoors.
The buttons are easier to control? than the thumbwheel switch.
The different vnas have different adapters, such as BNC, UHF and N connectors. I use BNC, UHF and BNC OSLThru cal kits for each device.
Mike N2MS
toggle quoted message
Show quoted text
On 08/19/2023 11:08 AM EDT David J Taylor via groups.io < david-taylor@...
wrote:
On 19/08/2023 13:34, Nuno Lopes - CT2IRY via groups.io wrote:
Hi guys, this is my first post here, I would like an advice to buy a new
VNA, my main operation is till 50MHz, but eventually I can operate till
1.2GHz, what would be a good VNA to buy, H4; F; SAA.
Can anyone recommend one.
Thanks
Nuno
CT2IRY
Welcome to the group, Nuno.
Do take a look at the Wiki:
/g/nanovna-users/wiki
Whatever you get, buy from the original manufacturer if at all possible.
Avoid
clones! I have several NanoVNA models and am happy with the H4 and its SMA
connectors (the H4 is reputed to need regular charging every few months as
the
physical on-off switch still leaves some slight drain).
Consider whether you want to use it outdoors, and whether SMA or N-type
connectors are better for you. Do you need to measure crystal filters?
Others will doubtless chip in with their own choice!
73,
David GM8ARV
--
SatSignal Software - Quality software for you
Web:
Email: david-taylor@...
Twitter: @gm8arv
|
Hi, I just got my SAA-V2 clone 3.2" "black and gold" (info link ) from ebay.
I'm very happy with it. Cost less then $100 and cover up to 4GHz can also measure my wifi and cellphone gears.
Have a good day.
FC
|
On 19/08/2023 13:34, Nuno Lopes - CT2IRY via groups.io wrote: Hi guys, this is my first post here, I would like an advice to buy a new VNA, my main operation is till 50MHz, but eventually I can operate till 1.2GHz, what would be a good VNA to buy, H4; F; SAA.
Can anyone recommend one.
Thanks
Nuno
CT2IRY Welcome to the group, Nuno. Do take a look at the Wiki: /g/nanovna-users/wikiWhatever you get, buy from the original manufacturer if at all possible. Avoid clones! I have several NanoVNA models and am happy with the H4 and its SMA connectors (the H4 is reputed to need regular charging every few months as the physical on-off switch still leaves some slight drain). Consider whether you want to use it outdoors, and whether SMA or N-type connectors are better for you. Do you need to measure crystal filters? Others will doubtless chip in with their own choice! 73, David GM8ARV -- SatSignal Software - Quality software for you Web: Email: david-taylor@... Twitter: @gm8arv
|
Roger Need
Barry K3EUI
Ho-Ro
Donald S Brant Jr
David J Taylor