Please suggest alternative for Bode100 - Page 1
Forum section: electronics / general

author: aju11
author_rank: Contributor
timestamp: February 02, 2022, 04:23:37 am
content: Is there any low budget alternative for Bode100?Our Key purpose is to design EMI filters and analyze power supplies.We are a start-up company and cannot afford to invest much as of now.

author: MegaVolt
author_rank: Frequent Contributor
timestamp: February 02, 2022, 11:10:43 am
content: NanoVNA?

author: 2N3055
author_rank: Super Contributor
timestamp: February 02, 2022, 12:30:52 pm
content: Quote from: aju11 on February 02, 2022, 04:23:37 amBode100 is very good low frequency VNA with large bandwidth and dynamic range.It also has many specialistic modes and measurements.It is industry benchmark, and in a perfect world I would have one..That being said, scope equipped with FRA option will do most of the work on PSU and filters (Picoscope with FRA4PicoScope can be used with more than 8 bit Picoscopes). They will not do impedance analysis and other stuff BODE100 can, but they will do Bode plots.Keysight has good FRA on 3000T series, Siglent have very good one too, even on entry level scopes and generator combinations. SDS2000X+ is a combination of a good scope with built in AWG and FRA all in one.. Rigol also have FRA but that one is a bit unfinished.I ran Keysight 3000T, Siglent and FRA4PicoScope with 3 different Picos and they all gave exactly the same results when measuring some DUTs. Speed was comparable too. It gets slowish if you pick too much points, but you can always start with less points per octave, do sanity check and if it looks good run a detailed plot for final result..Mostly you will see less dynamic range (with 8 bit scopes) but that is mitigated with variable levels and autoranging on scopes. Mostly, biggest difference you will see is that these FRA on scopes are slower than BODE100. They take a bit more time to finish the plot. Most of the time plot will be as usable as one from Bode100, if frequency ranges are sufficient.I did run FRA on scopes with more than 8 bit (12 and 16bit) and then results are very close to what Bode100 would provide.One more thing is that you will need injection transformers and/or amplifiers/active injectors. Those you will need no matter what you choose to run the analysis with. Some of these can even be DIY(with good result, but with some effort) or even improvised in a pinch by using various signal/pulse transformers or even common mode chokes. There are several topics here where members demonstrated some very good designs...

author: DaJMasta
author_rank: Super Contributor
timestamp: February 04, 2022, 05:11:37 am
content: If you can find one, an AP Instruments model 200 can be pretty cheap and their XP legacy software will still run under windows 10. Their newer models are considerably more, but it's got that low frequency, high impedance network analyzer functionality that it sounds like you're looking for.You can also look for an LCR meter with a wide bandwidth, but my guess is that these will be more expensive, and if it doesn't have graphing capability built in, would require some remote software.

author: miro123
author_rank: Frequent Contributor
timestamp: February 04, 2022, 11:49:31 am
content: What are the requirements, e.g. BW?1. I have good experience with - Keysight 1000 series and Rigol MSO5074. The latest is often on sale ~700..750$. Both work good up until 20..25MHz. Combining DSO, serial line analyzer function generator + bode analyzer in one make then price winner. As already mentioned for PSU you need tranformer. I have build one and compared it with Pico. Send me PM for more details2. VNA are also great tool - mostly used by EMI filter design. I assume that you are mostly testing conducted. For radiated there are other tools.All in all - next to standard equipment you need few accessories. This must be taken into account by the final price

author: JohnG
author_rank: Frequent Contributor
timestamp: February 04, 2022, 07:10:03 pm
content: There is also the HP3577. You will need to use GPIB/IEEE-488 if you want to communicate with it (and you probably do). It's a boat anchor for sure, but very high performance. You can probably do without the s-parameter test set, though it's nice to have.John

author: precaud
author_rank: Frequent Contributor
timestamp: February 05, 2022, 02:25:33 pm
content: Quote from: 2N3055 on February 02, 2022, 12:30:52 pmCleverscope will do Bode and impedance.I second the used AP Instruments recommendation, though their software isn't nearly as complete (or friendly) as the Bode 100's.

author: voltsandjolts
author_rank: Unknown
timestamp: February 05, 2022, 02:48:57 pm
content: Cross-reference to thread about impedance analysis using bode plot data:https://www.eevblog.com/forum/testgear/rlc-impedance-viewer-for-picoscope-bode-plot-data/

author: voltsandjolts
author_rank: Unknown
timestamp: February 05, 2022, 02:51:50 pm
content: Theanalog discoverybode plotter is actually quite good thanks to the 14bit converters, if 10MHz is enough bandwidth for you.