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What is a "warm" wire in the CH0 connector??

The author discusses this some and there are numerous response graphs in the QEX supp files. Can you read the article or do you need a copy
Dick K9IVB

In my last firmware i add option DONE IN RAM (in calibration menu)
This allow do calibration and not save it in flash (prevent flash damage from frequent rewriting, and not need use save slot)

This calibration reset after device power off.

On 9/21/21 2:05 PM, William Smith wrote:

OK, that's adjustable for different jacket/braid/dielectric/center diameters, do you have to swap the cartridge for different strip lengths?

73, Willie N1JBJ

yes and no. There's a bunch of "slots" into which the blade drops to adjust the "length". Then the hex screw sets the depth.

If you're using two kinds of strips consistently, then getting extra cassettes is useful. I just used to keep notes on where to put the blade, and how many turns of the hex for each one. And eventually, the blade does get dull (esp the one cutting the shield in the middle).

On Sep 21, 2021, at 4:58 PM, Jim Lux <jim@...> wrote:

On 9/21/21 1:20 PM, William Smith wrote:

Hey Jim,

Do you have a pointer to the fancy adjustable one? I've been having a hard time finding anything other than 2 and 3 blade non-adjustable ones

73, Willie N1JBJ

Paladin CST Pro

looks like it

On Sep 21, 2021, at 2:56 PM, Jim Lux <jim@...> wrote:

the fancy adjustable one

Depending upon the version of the NanoVNA and the firmware version the
NanoVNA uses 101, 201, 301, or 401 points of measurement. That says that if
you have a calibration range of 3 to 30 MHz and the device is using 101
points the NanoVNA measures approximately every 267 KHz.Now if you reduce
the range to the 7050 to 7060 MHz that is 10 KHz. That is very much less
than the 267 KHz used by the device. Yes the device is still calibrated for
the 3 to 30 MHz but may not accurately measure the narrower span. EXAMPLE
1st point is 3000 KHz
2nd point is 3267 KHz
3rd point is 3534 KHz
and so on.......

I would recommend that you calibrate the 3 to 30 MHz range for
board measurements but also due an additional calibrate in the specific
frequency range of interest. If you calibrated in the 7000 to 7100 range
then there will be a measurement point every 990 Hz.

The basic rule is to recalibrate with changes in frequency or changes in
jumper cable length.

The numbers quoted are approximate.

Regards,


*Clyde K. Spencer*

Joe,. The Nano has discreet frequency steps you can set. Since you have an H4, you can have up to 401 steps between the lowest and highest swept frequencies.?
You need to keep this in mind as everything between the steps is interpolated.?


On Tue., 21 Sep. 2021 at 7:28 p.m., Joe WB9SBD<nss@...> wrote: Thanks, I was thinking of something like that.

Joe WB9SBD

Joe,

Another good way to learn about the NanoVNA is to read old posts in this group. Many typical questions have already been answered. For example this post which deals with your question.

/g/nanovna-users/topic/73210908#12819

Roger

On Tue, Sep 21, 2021 at 04:03 PM, Joe WB9SBD wrote:

is it still calibrated?

How about really narrow like 7050 to 7060 Khz

still calibrated?

Joe WB9SBD

Joe,

The best way to learn about your NanoVNA is to "learn by doing". Calibrate your unit for 3 to 30 MHz. and make a measurement of a narrow band like 40M by zooming in. Then calibrate for just the 40m band and make a measurement. Then compare the two and see how different they are. This is a great way to become proficient with the NanoVNA.

Roger

Thanks, I was thinking of something like that.

Joe WB9SBD

Always calibrated however, unit does interpolation. Therefore, if you desire best accuracy over a given range, then cal over THAT range.

Ok,
say I set up Stimulus for 3 to 30 Mhz.

And then do a calibrate

Open
Short
load.

Now it is supposedly calibrated for anywhere between 3 and 30 Mhz correct?

Now I look at the who range and decide to zoom in on say 7 to 7.3

Start 7 Mhz
stop 7.3 Mhz

is it still calibrated?

How about really narrow like 7050 to 7060 Khz

still calibrated?

Joe WB9SBD

OK, that's adjustable for different jacket/braid/dielectric/center diameters, do you have to swap the cartridge for different strip lengths?

73, Willie N1JBJ

On 9/21/21 1:20 PM, William Smith wrote:

Hey Jim,

Do you have a pointer to the fancy adjustable one? I've been having a hard time finding anything other than 2 and 3 blade non-adjustable ones

73, Willie N1JBJ

Paladin CST Pro

looks like it

On Sep 21, 2021, at 2:56 PM, Jim Lux <jim@...> wrote:

the fancy adjustable one

3 blades cut jacket, shield,dielectric. I enjoy mine.

Hey Jim,

Do you have a pointer to the fancy adjustable one? I've been having a hard time finding anything other than 2 and 3 blade non-adjustable ones

73, Willie N1JBJ

Yes, I can calibrate the device, but when doing measurements, I get a lot of lines in a mess. If you have a look at the photo - measurement - you can se a curve form, but rather thick. The form of the curve is correct, but there is a big difference between measuring point, and this makes the "thick line".

If time permits tomorrow, I will make a "correct measure ment with my NanoVNA-F and compare the result.

Karl Jan

I have tried 3 different calibration sets, they all get the same result. Measuring at DC is ok. My NanoVNA is a SAA-2N, this is a device with N-connectors, so I don't think they have don their job...

Karl Jan

It would depend on what coax you are working with.
Lately I've been using RG316, quite by accident I discovered that I can
neatly remove the outer jacket with my Ideal strippers by using the 14AWG
gate, carefully close the gate and stop just before the strippers start to
pull the wire through the gate, release pressure on the handles, when
possible rotate the cable 90 deg, repeat. Use your thumb nail to slide the
jacket off. Now I cannot attest that there is no damage to the shielding,
my eyes are 70 years old but I use magnifiers and I haven't noticed any
shield strands coming adrift.

Hope this helps someone.

John
VE7KKQ

On Tue, Sep 21, 2021 at 11:57 AM Dragan Milivojevic <d.milivojevic@...>
wrote:

It depends what you mean by pro.
While I was working for a cable provider the service men
used cheap tools like these:



I usually use the first one for small diameter coax as it is much
faster than adjusting the second one.

For larger diameter coax, pipe cutter with a sharp blade works
great. This style:
Also get cable cutter pliers, especially when cutting larger diameter
cable.
Once you try it you'll newer go back to usual wire cutters that mangle up
the
dielectric and center lead. Something like this, but these are usually
cheaper
to get locally then on AliExpress:





On Tue, 21 Sept 2021 at 18:57, kk7xo via groups.io <kk7xo=
[email protected]> wrote:

I have a ratchet crimp connector and can install various types of
terminations. But what tool(s) do the pros use to strip coax? Any
suggestions?

It depends what you mean by pro.
While I was working for a cable provider the service men
used cheap tools like these:



I usually use the first one for small diameter coax as it is much
faster than adjusting the second one.

For larger diameter coax, pipe cutter with a sharp blade works
great. This style:
Also get cable cutter pliers, especially when cutting larger diameter cable.
Once you try it you'll newer go back to usual wire cutters that mangle up
the
dielectric and center lead. Something like this, but these are usually
cheaper
to get locally then on AliExpress:




On Tue, 21 Sept 2021 at 18:57, kk7xo via groups.io <kk7xo=
[email protected]> wrote:

I have a ratchet crimp connector and can install various types of
terminations. But what tool(s) do the pros use to strip coax? Any
suggestions?

On 9/21/21 11:14 AM, William Smith wrote:

For instance, this is still a work in progress, but, for RG-8x:

BNC Connectors from HRO: Lands Precision BNC-10Z-DGN
N-type for RG-8x: (Silver) and (nickel)

Strip Tool: LP HT-322
Crimp Tool: LP DL-801G

Go together well.

The same tooling works with RG-58 and LP BNC-10F-DGN

Note that while the stripper is nearly perfect for RG-8x BNCs, it might require a little fidding for the other cables and connectors. The LP spec sheets show a wide range of strip lengths, and even LP doesn't sell the appropriate strip tooling. Go figure.

YMMV.

That's why I eventually got the fancy adjustable one.? I had a single purpose for crimp on to RG58 for thinnet networks, worked great. But didn't quite work for other sizes. With the adjustments, I could fiddle with it until it was perfect for the connectors I had and the coax I had.
They work up to about 1/2" diameter as long as it's a smooth shield. They won't work on corrugated shields (although I'm sure someone makes a stripper for that)

It's kind of like the (wretchedly expensive) tools for semirigid and SMA connectors.? Get the right tool set up right, and you can crank out dozens of cables in a day, all perfect.