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In order to make the comparison of the different coax cables easier see the following.

I have attached a coax cable data comparison table:
Coax-cable_comparison-table.png

And a picture of three of them with SMA male plug:
LTDZ_coax_cables_DSC08126.jpg

For measuring I like the best RG316 because of the flexibility.
I had not a problem up to now with them.

The semi-rigid cable RG402 is intended for internal wiring only,
not for often bending.
not for often bending.

73, Rudi DL5FA

Hi qrpdds

Please do a S11 dB measurement after Thru calibration with + - 1dB or less per division . You are doing phase measurement which is very sensitive to minor movement of the cables. Do not search for Ghost's ?

Kind regards

Kurt



-----Oprindelig meddelelse-----
Fra: [email protected] <[email protected]> P? vegne af qrp.ddc@...
Sendt: 10. oktober 2019 12:49
Til: [email protected]
Emne: Re: [nanovna-users] Very poor thru (barrel) supplied with NanoVNAs



On Thu, Oct 10, 2019 at 01:25 PM, Kurt Poulsen wrote:

What you should observe is a S21 dB measurement of a DUT, that makes

sense and you will see no difference.

I see difference for S21 between rg405 and rg174 cable in attachment.

I would not waste my time with these questionable connectors and cables. I am use Amphenol adapters, SDR-Kits Calibration kits and quality SMA cables that I rescued from scrap HP test equipment.

Mike N2MS

Hi dear all! I'm new to the forum, I didn't manage to start a new topic, but today my SMA 50 Ohm load stopped working. It worked yesterday when I received my NanoVNA, but today it does not. All the cables/wires and inputs are double-checked with another load made of PL-259 and 51 Ohm DIP-resistor. Surprising but true.

Considering the cost of a nanoVNA, I wonder if anyone sells these parts.? I worry about the same thing happening to me.
I do have a cal kit from an old VNA I could use, with the proper adapters to get to type N.? And I have a Tektronix BNC through termination that would suffice for most frequencies.
Bob

Checking is better than assuming 'new = ok'.

My 50 Ohm SMA load that came with my NanoVNA was open from the beginning.
The double female SMA barrel on one side didn't screw all the way, just 2 threads.
I got a small refunding, but I had to wait for the replacement from two other Companies,
where I bought (to be on the safe side) two ea. new ones, as the NanoVNA seller didn't
have any spares. The two new loads bought together differ (measured by DC Ohm-meter)
by > 1 Ohm.

But what shall I say for some 50 $ total price? No issue.

DJ7BA

-----Ursprüngliche Nachricht-----
Von: [email protected] <[email protected]> Im Auftrag von RW3ACQ via Groups.Io
Gesendet: Donnerstag, 10. Oktober 2019 19:02
An: [email protected]
Betreff: Re: [nanovna-users] Very poor thru (barrel) supplied with NanoVNAs

Hi dear all! I'm new to the forum, I didn't manage to start a new topic, but today my SMA 50 Ohm load stopped working. It worked yesterday when I received my NanoVNA, but today it does not. All the cables/wires and inputs are double-checked with another load made of PL-259 and 51 Ohm DIP-resistor. Surprising but true.




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