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Think "terminal velocity" . . .

The worst were car stereo amplifier output Watts. Still trying to figure out how they got 300W out of a 12W chip.... 73 -Jim NU0C "Doug" <jdkearney@...> wrote:

Yes, the VNA is calibrated with short, open, and a 50 Ohm load through the cable. Though at 125kHz a 6" cable should not make much difference.

Is the NanoVNA calibrated to the end of the coax at the antenna with an open, short, and load?

Or GMRS radio range! Doug? -? VA3DKA

Remember, marketing has the last word when a product is finally released for sale. Also, manufacturing variations also play into the whole picture. I wouldn't be too concerned with anything less than

if in manufacturers smith is shifted in the inductive area ... how can he claim an swr 1:1 and 50 ohms?? just thinking? (i have not seen the plots) dg9bfc sigi Am 16.07.2022 um 18:20 schrieb KENT

There aren't many ships (real ships that don't run on underwater wings like the new Independence) that can outrun a torpedo. Even an aircraft-carrier running at 46 knots is NO match for our modern

12 pound per square foot plate is thicker than 10 pound per square foot. They always go thicker, but the point is they often go different than the designer's plan. If you design a ship to go 24 knots

Oh, never compromise when safety is an issue or anything else for that matter. I'm assuming #12 plate was thinner, not a good choice. My 2 cents worth. Mike C.

Then I'd go for "what's the mfr's test fixture/reference design look like" (if there is one..)

In my case, this will be a transmitter with the antenna driven by a MOSFET H-bridge with less than 1 Ohm source impedance and only a few inches of wire, so a low antenna impedance means more power can

I have 4" x 10" sheets of brass and aluminum I can hold up to the antenna and see the VNA plots move a bit, and steel moves them a bit more, but nothing on the scale of the difference between my plots

Indeed.. at 125 kHz and low power for embedded systems, 50 ohms matched circuits would be pretty unusual. Consider the AM radio in a car - not 50 ohms. At low frequencies (consider 60 kHz WWVB

Does the mfr provide a "how we measure it" document? Test fixturing, sample circuits, etc. are important. You'll see this kind of thing with devices designed for use in embedded systems - For

Hi Doug, having done quite a few RFID antennas, that 1 to 1 is rather optimistic. One thing to consider, do you have any other metal within a foot or so of the antenna?? ?You can easily see a pair

I have a 125 kHz RFID antenna consisting of a coil and series tuning capacitor. The manufacturer supplied plots of the SWR and Z of the antenna showing a nice 50 Ohm 1:1 SWR at resonance. I have tried

exactly !

Hey Dave, I agree with you, my TI99/4A is still my favorite. (just kidding but I did use it for years) I now use win 7 and buy malware to keep it clean. Mike C.

Your display looks OK but 462 ps would be the value for a very short transmission line - about 4.5 cm long. What is the length of your transmission line and what kind of coax is it? Here is a video