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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

Hi Tuck(?) Whether a load shows a return loss of 50 dB, 30 dB or 70 dB depends upon what load was used to calibrate the VNA. As you can see from the chart, all three loads exhibited better than 70 dB

This seems like taking an arbitrary resistor from the bin and calibrating your ohmmeter to it. From that point you only know how other resistors compare. This also reminds me of some of the time-nuts

It should be much better in the field on a proper HF antenna, both because of the counterpoise and also the lower frequencies involved. Well at least your HF antenna should have a proper counterpoise,

Hello Peter, On the device itself. So I will elaborate a little more, as I would like to use one nanovna at the field, as a simple SWR measurement tool, and of course operate it handheld. Maybe it

Thank you Warren. This is no argument over a pin head. Do you believe any of your loads are 50dB or better or even 38dB or better. How do these figures degrade with Frequency?Sent from my Samsung

Are you seeing the effects of your hand on the instrument or on the antenna? Remember also that those antennas are dependent on a counterpoise, usually the HT and your body, so you will see

I don't? think this vna calibration just arbitrarily sets the 50ohm dummy to the noise floor. If it is based on a 3 load measurement then it must use Thomas Baier' s DG8SAQ procedure which is to find

Hello team, While I was measuring an handheld VU antenna, I noticed that the nanovna was suffering of "Hand capacitance" influence. My unit is an original one, shielded. What can I do to improve it?

Just a slight correction -- actually, I should have said that the load's resistive "deviation from 50 ohms" must be less than 0.032 ohms. Sorry about that! - Jeff

Warren, excellent illustrative post demonstrating that if a VNA measures a load to have a return loss of 70 dB, it isn't necessarily so. Over the years I've purchased a number of 50 ohm loads (generic

Warren, thank you very much for this clear and concise explanation complete with an example. Now everyone and can get back to 'playing' with their new toy/device/instrument. Cheers, Larry Ps..I like

I am not sure if I am adding to or further confusing this discussion which has descended into, in my opinion, an argument over the number of angels on a pin head. First, when a three point calibration

All, First warning. Please do not create posts that do not contain factual technical information or questions about that information. Please refrain from publicly creating posts that in any way

Hello, I thank you Hugen for your reply. Now its clear, and over 800MHz I don't have any interest so I played safe and already flashed the 800MHz version. Where can one find the FW change log? (Maybe

You are in cloud cuckoo land to think that I believe I am measuring 70dB. Read my post carefully and tell me what are we all measuring when the instrument says 70dB. And stop pushing your expertise

In order to measure a return loss of X dB with an uncertainty of 1 dB you need a load with a return loss of of around X + 10 dB. So to guarantee a return loss of 70 dB you would need a load with a

I am afraid your statement is contradictory. 70dB is the minimum return loss calculated by this instrument. The noise floor is the minimum amplitude voltage the detectors can measure sure but they are