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Gary, Where can I find info on using the tinySA as an rf sniffer? Looked at the video list and on the home page but it is not addressed there. Thanks, John K?JHL

Set bandwidth at maximum (4k on H4), connect antenna to CH1 port, and you can get signal strength in 4kHz range for every measure point. So if measure on 401 point you can measure in span ?401*4k =

Get a tinySA. Works great for that purpose. You may need shielded loop probe if the interference is caused by current or just the telescoping antenna included and an external LNA to get the best

For what it's worth, I have a similar OFC dipole setup to what you describe, and the measurements from my nanoVNA-H4 and my MFJ-226 are almost identical. So what you are describing is not what I

Has this been implemented for a fix to the issue of protection? I would like to update my unit with the fix.Thank you very much,BillW4MXT

This is definitely something to keep in mind when you are testing an antenna at a tower site, like at a repeater site. Other transmitters at the site can affect the readings. I do antenna testing and

Has anyone used a Nano VNA as an RF sniffer around the home, a Radio Amateur friend of mine has an annoying RF signal that affects his receivers in his shack, we have been using a small commercial

Clifford - Just took a look at your schematic. --- I see you reverse biased one of the diodes to Vaa (3V) and the other to ground. Why not both to ground? ---- It look like you used 10 k resistors

Hi Bill, The MFJ seems to be the outlier. Consider that a man with a clock always knows what time it is. A man with two or three clocks can never be sure:) Other replies to your post point at other

Bill, The MFJ analyzers are not that accurate. I own a MFJ-259B and results will vary with battery voltage! There is a calibration procedure for them and I suspect some leave the MFJ facility without

The choke at the feedpoint doesn't mean that the coax is totally decoupled from the antenna - the fields from the antenna will couple to the shield of the coax. A symmetric dipole, with the

Manfred, The OCF Dipole has a common mode choke at the feed point. I ran a coax to my shack and connected all three analyzers at the same end of the coax and at the same physical position. The only

When I redesigned the HackRF antenna protection, I removed the useless TVS, a bi-directional 15V type (that will only activate after everything in the HackRF is already dead), and instead used

One thing that I did to make sure oranges were oranges and apples were apples.? I constructed a reactive termination for the analyzer.? Based on 10 MHz, I built up a series SMT structure of a 0603

Bill, I would suspect that all three of those meters are right, and that the antenna's behavior is changing according to what you connect to it! It's and OCF dipole, an antenna that is highly

Your question would be "is it a frequency measurement problem" or "is it a impedance measurement problem" - The first one could be answered by measuring a piece of coax that is shorted or open at the

I measured my 40M OCF Dipole with my NanoVNA-H4 and it shows that the minimum SWR of 1.68 is at 6.975 MHz. I had the loan of an MFJ-259C, and it shows the minimum SWR of 1.6 is at 7.14 MHz. I also

No, cost is very low, jut a few cents. During the design phase ESD strikes were applied directly at the input, it passed the tests. However, after my report of broken units, the designer (Gabriel)

That sounds great Mario! I'd love to see some write-up of what you found worked, and what didn't... anything that would make it easier for us also to get good test antennas.

I couldn't make even the small number of connections suggested with those little connectors. They died before. I put in parallel with each connector a pair of male-male pins used with IC sockets