Spectrum Analyzer recommendations for pre-compliance testing ? - Page 1
Forum section: electronics / testgear

author: snoopy
author_rank: Frequent Contributor
timestamp: October 17, 2018, 03:26:11 am
content: Looking at spectrum analyzers either new or used to do some pre-compliance testing among many other things that you can do with a good spectrum analyzer.What bandwidth is necessary ? Is 1.5GHz adequate or should I be aiming at 3GHz ?The Siglent ones seem to be good because of their low noise and they have a new low cost version which incorporates the option of a vector analyzer and other stuff.

author: DaJMasta
author_rank: Super Contributor
timestamp: October 17, 2018, 03:36:16 am
content: What sort of regulations are you trying to comply with? Who's? What sort of product?That should tell you bandwidth, though as I understand it, most of them don't get into the GHz range unless you're transmitting or you're operating at higher frequencies.... there are a lot of nuances of the laws in different places and for different classes of devices and while a few do require a lot of bandwidth, but most basic stuff will only get to a few hundred MHz.

author: snoopy
author_rank: Frequent Contributor
timestamp: October 17, 2018, 03:42:19 am
content: Quote from: DaJMasta on October 17, 2018, 03:36:16 amOK the product I am working on has a high speed DSP which runs at 400MHz and clocks internally at 800MHz. It's for the domestic market. I am just concerned about exporting it to other countries. When should I be concerned about CE compliance etc ?cheers

author: tautech
author_rank: Super Contributor
timestamp: October 17, 2018, 09:28:21 am
content: AFAIK 1.5 GHz should cover most pre-compliance work but others more experienced should be able to advise you.The vast majority of my SSA3kX sales have been just for this but with the SVA now available it in some ways makes the choice harder should you later need higher frequency coverage.However if the VNA is of use SVA would seem the better option as you don't need a return loss bridge for most RF work and this saving alone makes the VNA option cheaper than it might otherwise appear.I've got both and they are nice instruments. I mainly align RF stuff, sniff the odd EMI and do antenna work so 1.5 GHz works for me ATM.

author: nctnico
author_rank: Super Contributor
timestamp: October 17, 2018, 12:31:31 pm
content: Quote from: snoopy on October 17, 2018, 03:42:19 amAFAIK the measurement is taken up to 6 times the highest frequency. However in my experience most of the problems are below 1GHz. So unless your PCB layout really really sucks a 3GHz spectrum analyser should do just fine. Whether to buy the Siglent SA or a used one is up to you. A used one is likely to offer more bandwidth but it will also be bigger, heavier and noisier (sound).Another item you'll need for EMC work are H-field probes. I can recommend the ones from RF-Explorer.

author: snoopy
author_rank: Frequent Contributor
timestamp: October 18, 2018, 06:12:30 am
content: What's a good 2nd hand SA to look out for ? The Agilent E4411B's seem to pop up quite a bitcheers

author: snoopy
author_rank: Frequent Contributor
timestamp: October 18, 2018, 06:13:33 am
content: Quote from: tautech on October 17, 2018, 09:28:21 amIs there an option for EMC testing module or does this come bundled with the instrument ?cheers

author: nctnico
author_rank: Super Contributor
timestamp: October 18, 2018, 06:21:09 am
content: Quote from: snoopy on October 18, 2018, 06:12:30 amGood deals can be found for Advantest or Anritsu. You don't really need EMC specific functions unless you are also going to build a special room with antennas. The typical method is to take a device to an EMC testing lab and then hunt down the sources of the frequencies that made the device fail the test. Back in the lab you take a base measurement before any modification and then you take measurements after a modification. For that you need H-field probes and (maybe) the averaging function.

author: tautech
author_rank: Super Contributor
timestamp: October 18, 2018, 06:52:48 am
content: Quote from: snoopy on October 18, 2018, 06:13:33 amOnly TG is included free so all other options are at additional cost.So just what might you need, well for the SVA1015X Siglent have lifted the option free trial times to 120 hrs operation which for some with spectrum analyser experience allows a good number of tasks to be completed before you even need think about purchasing any options. OTOH SSA3000X models only have 40 hours free trial time.At this time only Siglent Europe have put together SVA option packages as seen here on the Hamburg site:https://www.siglenteu.com/news-article/bundle-sale-on-spectrum-option/Normal pricing in USD is in the US Siglent store:https://store.siglentamerica.com/product/sva1015x/Some of the SVA options are the same as offered for SSA3000X and there should be examples in this thread:https://www.eevblog.com/forum/testgear/siglent-ssa3000x-spectrum-analyzers/

author: 2N3055
author_rank: Super Contributor
timestamp: October 18, 2018, 07:23:25 am
content: Signal Hound USB-SA44B is 900 USD, Get some near field antennas, maybe even a cheap TEM box, all for less than 2000 USD.It has precompliance support in software..

author: Apollyon25_
author_rank: Regular Contributor
timestamp: November 02, 2018, 03:01:22 am
content: Unless this has changed recently, the SA44B doesn't run the Precompliance section in the latest version of the Spike software.I have a SA44B and did precompliance and debugging with this, but if you want the fancy software you'll need the BB60C for this.When I talked to Signalhound about this a while ago, they said the R/T BW of the SA series doesn't guarantee peaks will be detected... The R/T BW of the BB60C is much faster. Their new baby is faster again.At some point I might upgrade to the BB60C.

author: TimNJ
author_rank: Super Contributor
timestamp: November 02, 2018, 03:34:29 am
content: Quote from: Apollyon25_ on November 02, 2018, 03:01:22 amI was literally just looking this up today. How did you run precompliance testing without the precompliance software module?

author: 2N3055
author_rank: Super Contributor
timestamp: November 02, 2018, 08:14:37 am
content: Quote from: Apollyon25_ on November 02, 2018, 03:01:22 amSorry, I didn't know that. I have BB60C. Thanks for info.