31–40 of 72 posts
It's a shame there are not very many devices working in audio range (sub 100khz). You still have to scout eBay for a device from the 80s-90s and they are still expensive as hell.
http://kokkinizita.linuxaudio.org/linuxaudio/
Look for Jaaa, near the end of the page.
Also interesting, although semi-unknown:
In ELI5 terms: What is a VNA? What are some exemplary, common things I could do with it?
It can tell you the effective Resistance, Inductance and Capacitance of the network at various frequencies. This is useful for tuning radio antennas or filters, or identifying bad cables or connectors.
You can precisely measure the length of a cable from one end (by measuring the time for the signal to reflect).
You can use it as a signal generator to illegally jam your neighbors TV signal, as another commenter here noted.
Not many common uses for it unless you think amateur radio is common.
Earlier quoted context omitted.
https://octopart.com/atsha204a-sshda-t-microchip-77761819?r=... But the original would have to see it coming and put this in the design, AND maintain a registry of all the valid chip serials. No hobbyist wants that headache.
What if I buy one real device and clone the serial number? This has been solved more than a decade ago but it requires hardware with secure storage to maintain a private key. Some centralized service holds the public key and can verify the device by asking it to sign something with the private key. This is basically every cell phone, quality IoT device, etc. The private key is installed in the factory, maybe provided…
Anyway, there's a litany of similar devices to fill whatever requirements you wish. SIM cards, for instance, are available in WSON8 MFF2 chips that you can directly solder to a board.
Make sure you read the "beware of clones" section carefully. There are some real shysters out there. Even the official UK reseller of the "lesser" sub 1GHz NanoVNA has been caught shipping cloned crap that doesn't even pass self test or work properly on multiple occasions. On to more optimistic things: these are really good. My neighbour is fairly deaf and has her television obnoxiously loud watching snooker until go…
Do you realize you just admitted to a crime?
Make sure you read the "beware of clones" section carefully. There are some real shysters out there. Even the official UK reseller of the "lesser" sub 1GHz NanoVNA has been caught shipping cloned crap that doesn't even pass self test or work properly on multiple occasions. On to more optimistic things: these are really good. My neighbour is fairly deaf and has her television obnoxiously loud watching snooker until go…
Whats the difference between the pro and normal version (apart fr 100$}.
It is shown in the specifications table. It looks like the Plus4 Pro has higher sweep rates (600 pts/sec) vs 200-400 on the Plus4, as well as a 10dB lower noise floor for the same amount of averaging. It seems that 6 dB comes from a tighter measurement bandwidth on the Plus4 Pro. Oddly enough, the accuracy is not stated in the spec table for any of the models. If they are the same (are they?), then it looks like you…
So what's the deal with the name "NanoVNA" being applied to like a dozen unrelated projects now?
In ELI5 terms: What is a VNA? What are some exemplary, common things I could do with it?
A Network Analyzer is an instrument to analyze the performance of a network of electronic components. Vector means that it analyzes phase as well. It can tell you the effective Resistance, Inductance and Capacitance of the network at various frequencies. This is useful for tuning radio antennas or filters, or identifying bad cables or connectors. You can precisely measure the length of a cable from one end (by measur…
Make sure you read the "beware of clones" section carefully. There are some real shysters out there. Even the official UK reseller of the "lesser" sub 1GHz NanoVNA has been caught shipping cloned crap that doesn't even pass self test or work properly on multiple occasions. On to more optimistic things: these are really good. My neighbour is fairly deaf and has her television obnoxiously loud watching snooker until go…
Be careful, this isn't something you should talk about/admit in public at all. Feds really don't like it when people mess around licensed bands.
They didn’t even do anything to someone we located and identified and collected evidence for who was jamming amateur radio repeaters.
In ELI5 terms: What is a VNA? What are some exemplary, common things I could do with it?
These low end VNAs have two connectors. A signal comes out of connector 1 and goes to connector 2. What happens to that signal is measured, including the change in amplitude (up or down) and phase shift (left or right.) Also, whatever signal bounces back to connector 1 is measured for amplitude and phase.
With that you can tune antennas, characterize filters, measure attenuators and amplifiers, measure distances on transmission lines, measure resonators, capacitors and inductors and some other stuff.
That's about as simple as it can be explained without resorting to baby talk.