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The leakage resistance changes noticeably with humidity.

On 2/8/21 8:45 AM, Dave Cole wrote:

Are you referring to PVC here?

yes, it's kind of like nylon in that way, and unlike, say polyethylene, PTFE, or polypropylene, which "as delivered" tend to be fairly hydrophobic.
From what I understand, depending on what kind of PVC you get, it might have contaminants in it (from remelting other batches), fillers, and the porosity can vary.
For example you can take 4 or 5 pieces of PVC pipe and put them in a microwave oven and they will not necessarily heat the same (a rough and ready RF absorption test, granted at a higher frequency than HF, but easier to do)
I've had the interesting experience of putting a piece of white PVC pipe on a lathe to cut grooves in it, and found that only the surface was white, and that there were black streaks in other parts.
I guess the story here is that if you go look up plastic dielectric properties, that's typically for a lab sample, not necessarily what's extruded on your hookup wire or plastic tubing.
That might also explain the varying results people get with stuff not designed for RF (or at least with properties controlled), like zipcord. For hookup wire insulation, all they care about is that it passes the breakdown voltage test, not that it has low dissipation.

On 2/8/21 8:45 AM, Dave Cole wrote:

Are you referring to PVC here?

yes, it's kind of like nylon in that way, and unlike, say polyethylene,
PTFE, or polypropylene, which "as delivered" tend to be fairly hydrophobic.

From what I understand, depending on what kind of PVC you get, it might
have contaminants in it (from remelting other batches), fillers, and the
porosity can vary.

For example you can take 4 or 5 pieces of PVC pipe and put them in a
microwave oven and they will not necessarily heat the same (a rough and
ready RF absorption test, granted at a higher frequency than HF, but
easier to do)

I've had the interesting experience of putting a piece of white PVC pipe
on a lathe to cut grooves in it, and found that only the surface was
white, and that there were black streaks in other parts.

I guess the story here is that if you go look up plastic dielectric
properties, that's typically for a lab sample, not necessarily what's
extruded on your hookup wire or plastic tubing.

That might also explain the varying results people get with stuff not
designed for RF (or at least with properties controlled), like zipcord.
For hookup wire insulation, all they care about is that it passes the
breakdown voltage test, not that it has low dissipation.

It's also fairly hygroscopic, but I doubt moisture content drives the dissipation.

? Jamie,
I think you've overwritten the existing copy with a dump from your device.
Delete the firmware you're trying to update with and get a new copy from the files section of the forum - use 1.0.45
...Larry

? ? On Monday, February 8, 2021, 7:53:04 a.m. EST, Jamie WW3S <ww3s@...> wrote:

? Yea, tried that, no joy....followed the W2AEW YouTube video ( mine is exactly like his), works great, until I restart, still says 0.5.0.....I’m going to try Larry’s modified GUI next....thanks...l

? On Feb 8, 2021, at 3:01 AM, Martin J.K. <martin.svaco@...> wrote:

? ?See Absolute_Beginner_Guide_NanoVNA_v1_6.pdf, page 49.
? The PDF file is in the file section .

? 73
? Martin 9A2JK

Jamie,
I think you've overwritten the existing copy with a dump from your device.
Delete the firmware you're trying to update with and get a new copy from the files section of the forum - use 1.0.45
...Larry

On Monday, February 8, 2021, 7:53:04 a.m. EST, Jamie WW3S <ww3s@...> wrote:

Yea, tried that, no joy....followed the W2AEW YouTube video ( mine is exactly like his), works great, until I restart, still says 0.5.0.....I’m going to try Larry’s modified GUI next....thanks...l

On Feb 8, 2021, at 3:01 AM, Martin J.K. <martin.svaco@...> wrote:

?See Absolute_Beginner_Guide_NanoVNA_v1_6.pdf, page 49.
The PDF file is in the file section .

73
Martin 9A2JK

See Absolute_Beginner_Guide_NanoVNA_v1_6.pdf, page 49.
The PDF file is in the file section .
73
Martin 9A2JK

On Feb 8, 2021, at 3:01 AM, Martin J.K. <martin.svaco@...> wrote:

?See Absolute_Beginner_Guide_NanoVNA_v1_6.pdf, page 49.
The PDF file is in the file section .

73
Martin 9A2JK

On Feb 8, 2021, at 3:01 AM, Martin J.K. <martin.svaco@...> wrote:

?See Absolute_Beginner_Guide_NanoVNA_v1_6.pdf, page 49.
The PDF file is in the file section .

73
Martin 9A2JK

On Feb 7, 2021, at 4:17 PM, Larry Rothman <nlroth@...> wrote:

?You saved the device few to the same name as the new fw... you've overwritten it.
Read the wiki about defuse and grab my modified exe.in the files section with better naming of commands.
Also, grab a new copy of fw out.of the archives and delete you prev one

Sent from Rogers Yahoo Mail on Android

? On Sun., 7 Feb. 2021 at 3:43 p.m., Jamie WW3S<ww3s@...> wrote:? I did do the verify, it says its loaded.....but whn I go to config, to
the splash screen, it says 0.5.0.....is that display a hardware or
firmware version?


------ Original Message ------
From: "DiSlord" <dislordlive@...>
To: [email protected]
Sent: 2/7/2021 3:36:39 PM
Subject: Re: [nanovna-users] upgrading firmware?

I think you use Upload Action button (this mean read firmware from device and store to selected file), check file size - should be 128k

Need use Upgrade oe Verify Action buttons, select choose... and select firmware (unpack again it from archive, i think you rewrite it by downloading from device). After use Upgrade button.