[KB9RLW] wanted to build a vector network analyzer (VNA), but then realized he could buy a ready-made one without nearly the cost it would have been only a few years ago. The network in this case, by the way, is an electrical network, not a computer network. You can use a VNA to characterize components, circuits, antennas, and even feed lines at different frequencies. The miniVNA Pro is economical and can exercise circuits from 1 MHz to 3 GHz. There are a few ways to actually create a VNA, but in concept, it is a sweep generator, a detector, and a means to plot the response at each frequency in the sweep. So you’d expect, for example, a resonant frequency to show a peak at resonance and a band reject filter to show a low point. One of the things interesting about the device is that it uses Java software. That means it doesn’t care much what platform you want to use. The software can show two different plots at once, so [Kevin] hooks it to his 20 meter antenna and shows how it can plot the SWR and impedance around the frequency of interest. The instrument can be USB powered with the same cable you use to connect the PC. Activator does not require user intervention, the entire activation process takes place in the background, just run the activator and a couple of minutes to check the activation status of Windows and/or Office. ![]() For miniVNA PRO2 No available update For miniVNA Tiny Current version is V1.0 No available update For miniVNA PRO Download Firmware miniVNA PRO V2.6 last. For miniVNA PRO2. No available update. For miniVNA Tiny. Current version is V1.0. No available update For miniVNA PRO. The is also third party software for the miniVNA that is easy to use and works a treat. Readings can be saved and plotted to PDF or JPG for reference or explaining issues on forums. Antenna tuning is a delight when you can see the whole band. ![]() However, it also has an internal rechargeable battery. That battery charges on USB and can operate the device with Bluetooth. We can imagine that being handy when you want to climb up a tower and connect it directly to an antenna as long as you stay in Bluetooth range of the PC. There’s also a phone app, so you can go that route, if you prefer and [Kevin] shows the device working with Android. Of course, you could probably rig a Raspberry Pi on your belt and then use WiFi to let someone on the ground remote desktop in to run measurements. A lot of possibilities. If you want to roll your own,, of course. If you want to get by a bit cheaper, there are. Posted in, Tagged,,, Post navigation. See also: the $500 PocketVNA. It has a significantly larger frequency range (500 kHz to 4 GHz) plus solid linux (and Win/Mac) support with it’s Qt based application. I’m using mine a ton to test/tune antenna and filters. Examples, Antenna measurements,,, Filter measurement: I tried all the rtlsdr, hackrf, and other bodged together with directional coupler scalar network analyzers but the real problem with those is calibration. Calibration is hard and without it you just get bonk results. The PocketVNA makes calibration a very simple and intuitive process. Vasco rossi discografia bittorrent. What kind of calibration options are available for these things? Cal kits for the network analyzers I work with are usually $5k and up. Granted, this is for equipment that goes up to K-band and beyond. But if I still have to shell out that much for cal standards, kinda defeats the purpose of spending so little on the analyzer itself. I could probably fabricate open / short / load standards, but they’d be narrow-band, and I’d need access to a better NWA to characterize them before defining the cal kit. Thru-reflect-line calibration is great, and much more forgiving of imperfect cal standards, but it’s only applicable to 2+ port analyzers. Maybe, maybe not. There weren’t really any low-end VNAs at the time. The VNAs from the ’80s were certainly behemoths, but they still radically outperform these offerings. Consider the 8753B, a mid-range product: 100 dB of dynamic range, source power variable from -5 to +20 dBm with continuous sweep from 300k-6GHz, input crosstalk better than 100 dB, dynamic accuracy of +/- 0.05 dB and 0.5 deg over a 50 dB input range, etc. Most of these devices spec none of these things, let alone approach those specs. Nice plastic shielded gear, with impressive high precision BNC reference plane:- ) One of the best “quality/price” ratio is, imho, the DG8SAQ “VNWA”, with an impressive documentation and a top quality (closed source) user interface. Far more evolved compared with the different software available for the mini-VNA.
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