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You are so correct, Don! I really don't care what the impedance or Vp is. Just parallel wire transmission line with low loss pretty much independent of SWR. You hit the nail on the head. Dave - W

Speaking of which - I saw a Hack-a-day article a few years ago where someone actually removed to top polarized surface of an LCD screen (very carefully) and made what looked like glasses out of the

One easy way of determining which end of a cable is bad is to connect the center connector to a wire and drag it across a portable radio's antenna. The good end will produce a lot more static.

interesting, but I'm not sure I buy his antenna test fixture: 1) in practice people hold the ht (or it's next to your body with a mic/headset) 2) he has no choke on the coax, so the coax is "part of

When you put the NanoVNA in CW mode it generates a square wave at that frequency. So you have a fundamental and harmonics of that frequency. I don't know what you mean by using the NanoVNA as a

A quick look at the line would be put a 450 ohm resistor at the far end and check at an odd quarter wave for the z on the nano. A given length of line has an odd number of quarter waves at

Hi Pierre, Operating a handheld transceiver has many imperfections, not the least of which is the operator himself who is a pretty good conductor (70% salty water in a human body) and will absorb or

There's two kinds of these - one is little tiny louvers (Light Control Film), the other is a circular polarizer (the reflection flips the polarization, so it gets blocked on the way back out). I'm not

There is a Japanese Web magazine, published in English, that had a 3 part series on testing "rubber duck" and other antennas on portable radios (HT's). They did SWR and field strength tests (Tx and

Can I change the tone? or does anyone even know what the tone generated is? IT would help a LOT with using it as a tone generator. thanks, John

All: Unless one is building a tuned circuit like a tuning stub or a series matching section, and in the typical use case of an untuned feeder for a non-resonant dipole, the exact impedance and

Pierre, the SWR fluctuations you see on the NanoVNA simply show you how a handheld antenna performs in normal use! It doesn't offer fixed, good SRW to the radio. Instead it varies according to what's

Hmmm...I’ve had to use those at work where my cubicle let sunlight impinge on my monitor. They work pretty well particularly if the sun is behind one and shining directly onto the screen. I wonder

How about using a piece of privacy glass/plastic - the type that allows you to see the display straight-on? I think it would block out light from the side.? Of course, it would be useless if the sun

Thank you so much. Some really good measurements. Excellent site. Dave - W?LEV [email protected]> wrote: -- *Dave - W?LEV* *Just Let Darwin Work*

That’s a good idea. If one could find one of those Tektronix ‘scope hoods that had the right dimensions so that the nanoVNA could be “tucked” into the hood such that it would fit tightly

I am thinking that, short of using a 3D printer to create a hood, a small box maybe twice the length and breadth of the nanoVNA that opens by the top lifting off, hinged at the back and with flaps

I’m envisioning the green plastic/rubber hoods we had on the old Tektronix oscilloscopes... the ones that were shaped to fit tightly against your face around your eyes... Nowadays the test equipment

What a beautiful suprise to see all theses answers ! Thanks to all ! Many Many Thanks to all ! Now i understand, i begin to understand. Why i try to do this : in order to try to get the best antenna

I was thinking something collapsible so it would be very small when not in use, but maybe that could be done by some clever 3D printer wrangler. (I've never played with any 3D printing.) -kb