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On Mon, Oct 14, 2019 at 07:33 AM, Starsekr wrote:

Jacon, if the resistors are missing, what does that do to USB communication?

This whole CC resistor discussion is meaningless for all of us who use USB 1,2 or 3 version from host side and original USB cable !!!!

They presence have only sense when you connect NanoVNA to host's USB-C socket via full USB-C cable.
You guys must remember identical mechanical nature of host/device type C sockets. Those CC pins are used to distinguish between
host AND device sockets. Host side should have pull-upped CC's, device side pull-downed, via those 5k1 resistors.

if the resistors are missing, what does that do to USB communication?

Indeed, that is the question, and I >>suspect<< is why some notice
more reliable nanoVNA connections via USB-2 hubs than to USB-3 hosts.

Are they just for using the USB as a sink (load?)

USB-C connectors are mechanically symmetric.
In order for half the 24 connections to NOT be redundant, electrical "keying" is wanted.

1) I >>guess<< that a single resistor from one CC to ground is wanted in nanoVNA for electrical keying
2) I >>suppose<< the original nanoVNA design, with DP1 tied to DP2 and DN1 tied to DN2,
was intended to suffice as symmetric don't-care.
3) I >>suspect<< that floating CCs provoke some USB hosts to misinterpret nanoVNA capabilities
and attempt sending signals via DP1 & DN1 that differ from those on DP2 & DN2
or even try to employ some lines not supported by USB-2 and not used by nanoVNA.

As with FAR too many other areas of commercialized innovation,
USB-C promoters evidently prefer acronyms to clear explanations,
with several documents "describing" functions to be accomplished by a USB-C cable,
called EMCA (really??), which make sense (to me) only if implemented by devices.

Jacon, if the resistors are missing, what does that do to USB communication? Are they just for using the USB as a sink (load?) for charging a battery through the USB port? Without them does the upstream usb just see the Nano as a low power sink?

Oristo, I just googled this term "USB TypeC CC resistor" and read docs from ST & Cypress that appeared:
(page 8)

You may do the same...

Is that resistor missing on current nanoVNA?

Definitely - starting from schematic diagram, where bot CC pins are NC.
There should be 5k1 resistors connected to device GND installed!

I do not understand; nanoVNA ties together DN and DP from either side of USB-C.
If both CC pins were terminated in nanoVNA,
then would that not inform USB hosts that both sides are available independently?

Maggie is very responsive and I was very happy to buy from hugen

The Alibaba store shows the following price scheme for the NanoVNA-H:

1-9 Sets 10-49 Sets >=50 Sets
$60.00 $39.00 $35.00

There is a larger than expected price disparity between single quantity and 10-49 sets, than between 10-49 Sets and >=50 Sets. I expect the NanoVNA-H will be bought in quantity by sellers and sold on eBay and other places for around $50. The current NanoVNA's without cases will probably drop to $40 or less.

- Herb

On Sun, Oct 13, 2019 at 05:53 PM, Oristo wrote:

Is that resistor missing on current nanoVNA?

Definitely - starting from schematic diagram, where bot CC pins are NC.
There should be 5k1 resistors connected to device GND installed!

USB TypeC CC resistor is also installed

Is that resistor missing on current nanoVNA?

This is the unpacked picture, D2 is already installed, and the USB TypeC CC resistor is also installed. Thanks to Maggie for making a beautiful gift box for NanoVNA-H. Thru Adaptor is currently not delivered, and orders placed after October 20 will be replaced with new Thru Adaptors. You can now buy it from Maggie's alibaba store .
Due to my lack of production experience, in order to ensure the quality of the goods, delivery may be slow. Maggie uses DHL to ship, but some European customers have to pay a higher fee for DHL. If you need to change the courier, you can contact Maggie to modify it. If you use China Post, you can save $10 postage, but it is slower.
Feel free to contact me if you have any questions about NanoVNA.

hugen

Were there photos to show if the back was shielded ?
-Kevin (KK4YEL)

Hi All

I have seen/heard someone got a Hugen NanoVNA-H clearly printed on the read and with display start-up screen also showing the NanoVNA trade mark

I believed I got an original Hugen by ordering from Alibaba.com where it was stated so and described as the Original one, but is was not branded Hugen.

Anyway try to go to A,ibaba,com and serach for NanoVNA-H and you is prompted a nice kitted version and in a case as well. The Thru Adaptor seem to be the new lossless one so I ordered one just for that ? No I am kidding.

Here is the picture for this nice kitted product

Kind regards

Kurt