Too Good to be True - Page 1
Forum section: electronics / testgear

author: olsenn
author_rank: Frequent Contributor
timestamp: October 25, 2013, 10:18:57 pm
content: Apparently, this 4GHz Agilent vector network analyzer is available for 750 EUR as a BuyItNow on eBay! Am I missing something here?http://www.ebay.co.uk/itm/Agilent-E4406A-Vector-Signal-spectrum-Analyzer-option-BAF-WCDMA-202-EDGE-GSM-/251358751988?pt=UK_BOI_Electrical_Test_Measurement_Equipment_ET&hash=item3a86262cf4

author: cyr
author_rank: Frequent Contributor
timestamp: October 25, 2013, 10:28:51 pm
content: The fact that it's a vector *signal* analyzer?

author: quarros
author_rank: Regular Contributor
timestamp: October 25, 2013, 10:33:29 pm
content: Quote from: olsenn on October 25, 2013, 10:18:57 pmWell it is a specialized test equipment for network analysis. It has a frequency span of 10Mhz so although it can work in a wide range of frequency it cannot show you a full spectrum, makes it useless as a spectrum analyzer . Thats the biggest "drawback" as I see.But if you already have a spectrum analyzer and and you want to have a greater resolution on a smaller frequency range than it is the perfect companion to you.Update: I just noticed, the seller is our fellow forum member KJDS.

author: ConKbot
author_rank: Super Contributor
timestamp: October 25, 2013, 10:55:37 pm
content: Quote from: cyr on October 25, 2013, 10:28:51 pmNailed it!Quote from: quarros on October 25, 2013, 10:33:29 pm*Cell phone network* analysis, or signal analysis, as its not a VNA, just 'network analysis' alone could be confusing. Also, the 10Mhz is the realtime bandwidth (I.e. it can digitize 10Mhz of spectrum and run a FFT/DFT on it in real time so you can examine modulation etc), as you can see from the options, it was meant to be used on CDMA, EDGE/ GSM networks. I havent used a VSA series analyzer before, only the newer MXA series which does support full span as a swept spectrum analyzer. No FFT real time unless your span is under the RTBW. I cant find anything in a brief peruse of the manual to indicate one way or the other, so find out for sure if youre interested in it as a swept SA. However I'd save my $$$ for a spectrum analyzer with a tracking generator, which is ridiculously useful compared to one without IMO.

author: quarros
author_rank: Regular Contributor
timestamp: October 25, 2013, 11:10:27 pm
content: Quote from: ConKbot on October 25, 2013, 10:55:37 pmSorry my terminology was not up to par.Anyways I found an interesting discussion about it:http://www.home.agilent.com/owc_discussions/thread.jspa?messageID=62538It seems it has a very low noise-floor.

author: ConKbot
author_rank: Super Contributor
timestamp: October 26, 2013, 12:12:40 am
content: Quote from: quarros on October 25, 2013, 11:10:27 pmNo problem, I'm sure terminolgy varies from place to place anyway. I'm sure there are cell phone network techs who havent touched a VNA and would call the VSA a network analyzer.Interesting that it doesnt support a sweep! I wonder if its not real-time then, I'd suspect not.A vector signal analyzer/realtime VSA is basically a tunable RF down converter ( i.e. converts 100-110 MHz to 0-10 MHz) to stuck in front of high-resolution/low noise DSO (I.e. it digitizes the waveform) where it then processes the signal to give frequency domain information instead of time domain. A realtime VSA can continuously acquire the data, and process it before the next chunk of data is ready. A 'plain' vector signal analyzer will have some deadtime.shows what signal analyzers can do vs swept spec-ans.