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See my message 469, Alan

I published my findings on the standards multiple messages in the past. I have the white unit and the black and again as I reported the black kit was supplied with significantly better RTL. If I

Then, given Thalus, you are somewhere between London and Berlin...... LOL OK... got it. Yes I did misunderstand you. I think we would find that as the RL numbers go past -40 dB their accuracy also

No you misunderstood me. I am only saying that if you have s 50dB load the nano is capable of returning that number consistent with your Spectrum Analyser RF bridge measurements which is impressive

It would be interesting for those with accurate meters to measure their loads supplied with their nanoVNAs. I am measuring 51.4 ohms with an AN870 meter. This was a white gecko purchase. Not great.

Not so fast my down under friend! LOL The highest possible quality in the load will lead to the highest quality measurements. I do not know the quality of the supplied load but, having lived and

Thanks Warren, I think we are now on the same page. So if I use 50dB quality dummies the nano vna can actually measure better than 38dB which is the supplied load. That is impressive for our

Yes of course, but all RLBs will give an absolute value of k plus the actual return loss of the DUT. For 50 ohm source and detectors this constant is theoretically 12.09dB but in reality changes with

An opencircuit on a transmission line has infinite impedance. A short circuit has zeroimpedance. An open circuit,short circuit, or pure reactance terminating a transmission line are incapableof

In a bridge, as used in the NanoVNA there is an internal 50 ohm resistor. You have no control of it and you probably can't actually measure it. The bridge will only be in balance when the external

No the return loss of open and short is theoretically 12dB. The RLB has a voltage factor of 8 and the transmission has a factor of 2 .?Sent from my Samsung Galaxy smartphone.

You are correct. In theory, a 6 dB attenuator will give a 12 dB return loss, which another way to test accuracy of the instrument. Stuart K6YAZ

I'm probably missing something here, but shouldn't opens and shorts give 0 dB of return loss, not 12? After all, their Gamma ought to be equal to 1. - Jeff, k6jca

As has been stated before, the importance of SWR or return loss for most practical users is not how little power is reflected (within reason) but at what frequency is the antenna actually resonant.

Tuck I am not sure if you are misunderstanding (I don't think so) or simply miss-stating the concept. A load, any load, does not have an inherent return loss. It only has a return loss as measured

An antenna without a counterpoise (ground or ground-plane) is just a piece of wire. If you are testing a "rubber duckie" I would recommend mounting it onto a piece of metal; even a piece of aluminum

Yes Warren, what you say is exactly what is done on any return loss bridge. You measure an open load, you measure a shorted load both of which should give 12dB return loss but in practice they differ

You can try a short coax loaded with low freq ferrites that fit tight on the coax. It helps (somewhat). Cal at the end of the coax

I saw similar effects myself when testing the antenna from a handheld transceiver. As Peter says it is to be expected as, in its intended use, the human operator together with the conductive part of

And, just to ground this discussion a bit, for practical purposes in the professional RF and video worlds any return loss in excess of 30 dB is considered excellent. A return loss of 30 dB for example