Radio Communication Analyzers: R&S, Agilent, Anritsu - Page 1
Forum section: electronics / testgear

author: colorado.rob
author_rank: Frequent Contributor
timestamp: March 05, 2020, 05:15:43 pm
content: I am looking at various radio communication analyzers. There are three in my price range ($500-$1000 USD) that seem common:R&S CMU200Agilent E5515CAnritsu MT8820ACan someone with knowledge of these units compare and contrast their capabilities? My understanding is that these include both an RF signal generator and spectrum analyzer. Will these units do vector signal generation and vector signal analysis? Are they controllable over Ethernet? Can the RF generator be used as a tracking generator for simple S21 measurements?Also interested in general knowledge about necessary or desirable options, known problems, etc.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: March 06, 2020, 12:52:45 pm
content: Quote from: colorado.rob on March 05, 2020, 05:15:43 pmFirst, forget the E5515C. It's a waste of money unless you really want to work with older (ancient?) cellular standards. These boxes are essentially modular systems which require a specific version of software, board revisions and chassis version to work, and the non-cell capabilities are extremely limited.The other two, R&S CMU200 and Anritsu MT8820A, are much better options as they are easily usable as general purpose instruments. Especially the CMU200 (as well as it's cousin CRTU-RU) has a very nice UI. The spectrum analyzers in both are fully digital and perform quite well. The RG generators are good for CW (the CMU200 can also do some simple modulation) but none can't be used as tracking generator out of the box (there are hacks for the CMU200 for that, though). Both are controllable via GPIB (the network ports, which on both were optional, were meant for cell data transmission). There's no vector analysis and no vector generation outside of the special purpose cell functionality.Of both devices I'd go for the CMU200 as it's more flexible (there's also an optional audio analyzer), has the nicer UI and there is a wider availability of parts and documentation for it. It's also pretty maintenance-friendly.Having said that, for <$1000 the Agilent E7495A/B will also fit inside your budget. It's a portable Base Station Tester (10Mhz to 2.7GHz) and contains a spectrum analyzer, CW RF generator (which can also generate a set of pre-defined mulated signals), and cable and antenna analyzer which can be used as a poor man's network analyzer (there's no phase information, though). It also has a built-in GPS timebase.There is tons of informations around for all of these devices, just use the forum search.

author: Bicurico
author_rank: Super Contributor
timestamp: March 06, 2020, 01:58:02 pm
content: Before you fork out your budget on the mentioned devices, consider that they are old devices and may break soon after you buy them.The R&S CMU200/CRTU have for instance one huge issue: when the DSP module inside the digital board breaks, you are screwed. There is no information, documentation or replacement parts. You will need to get a new (used) digital board. Why they fail is beyond me. More info here:https://www.eevblog.com/forum/repair/cmu200-rohde-schwarz-hangs-during-basediscoveroptionsbegin/Another common issue with the CMU200/CRTU is that the RF front-end is broken. This can be repaired, but that is not easy and implies desoldering a BeO capacitor.Finally, you have to mind the RXTX board, which often fails self-calibration. Again, no documentation on how to fix that. Simple cleaning oft the board will not do the job.All in all, the CMU200/CRTU consists of several boards in a silver alloy case, which gets heavy oxidation over time and the inner electronics get soaked with the silicon heat transfer pads, which tend to degenerate into some form of oil or grease. Nasty stuff.Get a cheap HP/Agilent 859x and you will be screwed if the PSU breaks. I have 3 (!) of them, all broken, and was unable to repair any. Again, no documentation at all, complex PSU with 3 boards and custom IC's.I am not sure about Anritsu, due to lack of experience, but again: if anything fails, you are on your own.So either get these second hand devices for a really cheap price (as low that you can actually buy two units and keep one for replacement parts) or be sure you know how to do repairs and have the required equipment.Otherwise consider buying a new Siglent SSA3000X (or the newer Plus model). These come with warranty and modern GUI.Regards,Vitor

author: Ice-Tea
author_rank: Super Contributor
timestamp: March 06, 2020, 02:02:54 pm
content: Re: CMU200. I've had a few dozen passing by over the years. I've had none with a broken DSP module (but have supplied one to help fix a machine). Same with a dead front-end. I have had one or two duds (that may or may not be due to the BeO cap) but it doesn't seem to be "common".Units failing self call *are* very common. I'd say about half of them or so fail that.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: March 06, 2020, 08:09:24 pm
content: Quote from: Ice-Tea on March 06, 2020, 02:02:54 pmSame here. Several CMU200s and CRTUs (>30 of each) and not a single defective DSP or front end.

author: colorado.rob
author_rank: Frequent Contributor
timestamp: March 07, 2020, 11:37:12 pm
content: Thanks folks. Really helpful information. What about a vector signal analyzer? Any experience with the Agilent E4406A? I think that may be a bit out of the budget, but I may be able to swing it if it has what I need. I have an E4433B for signal generation. It looks like they may pair well together.

author: eevcandies
author_rank: Regular Contributor
timestamp: March 08, 2020, 10:54:43 pm
content: How about a nice MS8609A 13 GHz spec analyzer (approx $950) & a R&S SMHU 4.3GHz generator...you can have a lot of fun with those.

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: March 09, 2020, 11:33:39 am
content: I use an HP 8935 E 6380 Service Monitor, there is a "Family" of these units.Fine for one GHz and below.You can get one of these easily for less than 1K on E BayThere is a company that specializes in this line of monitors, Amtronix, they sell parts and can help with problems.Their prices are higher than a private sale.Take a look at their website and look for a page that compares this family of Service Monitors.http://www.amtronix.com/usequip1.htmThere is a user group for these units on Group.iohttps://groups.io/g/HP8924-Family-Spectrum-Analyzers/topicsI also have an E 7495, They are OK. The GPS disciplined oscillator will not work unless you reprogram the unit. I have done this.The RF generator is really not much help as it will not put out a single frequency, really just a noise generator.Generator starts at 375 MHz, NO HF. However it has a nice RF power meter if you get the power head.I much prefer the HP 8935 for working on HF radios.Wally

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: March 09, 2020, 01:15:13 pm
content: Quote from: colorado.rob on March 07, 2020, 11:37:12 pmThe E4406A is a great instrument if you need to look at complex signals with less than 10MHz/100MHz BW, but as a general spectrum analyzer it's pretty poor.There are various threads discussing the E4406A VSA which should give you plenty information.Quote from: eevcandies on March 08, 2020, 10:54:43 pmThe MS8609A (and its smaller brother MS8608A) are great SAs but most of them were used in cellphone testing and come with very high attenuator switch numbers (it's a mechanical attenuator with a limited life, there was an electronic switch as option which is more durable but this one is rare). Also, it has no DC protection, there is no service manual and it is pretty loud.However, if the budget can be stretached >$1k then the JDSU/Gencomm JD740A Series (i.e. GC747A) could be a good alternative. Portable unit with nice XGA display, has an 4Ghz SA, VNA (i.e. it does phase, too), power meter, RF generator and GPSDO. The built-in interference finder is great for fox hunting as it can import a map from Google Maps and use it for triangulation.

author: colorado.rob
author_rank: Frequent Contributor
timestamp: March 10, 2020, 02:47:31 am
content: Thanks. I think I'll take a closer look at the E4406A. I have a reasonable SpecAn with tracking generator and reflection bridge. A VNA with smith charts would be nice to have but not a necessity at this point. Complex signal analysis is what I am hoping for. I am planning to play around with complex modulation/demodulation techniques with a PlutoSDR and would like to have some good lab instruments to see what I am doing.Thanks for pointing me to the GC747A. I had not heard of that one before. If I were in the market for a VNA, that would certainly be a top contender. Actually, it's really tempting in its own right. I might have to think on that.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: March 10, 2020, 06:32:15 am
content: Quote from: colorado.rob on March 10, 2020, 02:47:31 amThe E4406A would be a good device for this, but it only really shines when combined with the Agilent 89601A VSA software.QuoteWell, it does Signal Analysis as well, so there you go

author: colorado.rob
author_rank: Frequent Contributor
timestamp: March 10, 2020, 09:28:13 pm
content: Quote from: Wuerstchenhund on March 10, 2020, 06:32:15 amI didn't see that mentioned or demo'd anywhere when looking for information on the JDSU/Gencomm units. I think the downside to the GC747A is that there is a lot less information about it than the other brands and models mentioned. I would really love to be able to compare this sort of equipment side-by-side.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: March 11, 2020, 08:15:28 am
content: Quote from: colorado.rob on March 10, 2020, 09:28:13 pmOperating manual:http://ca.celladvisor.updatemyunit.net/archives/JD740A_User_Manual_R09.0.pdfPage 31ff Modulation Analysis MeasurementsQuoteA lot of information can be found in the manual.Side-by-side comparisons will always be difficult unless you get all the instruments together and do a comparison, which for 2nd hand equipment would probably mean you'd have to buy them all.I do have an E4406A (not worth selling, and occasionally useful) and it's an interesting tool when used with the 89601A VSA software, but it's also slow, with slow interfaces (GPIB and 10Mbps Ethernet), and when I needed modulation analysis the GC747A was easier to use than setting up the E4406A and the VSA software.

author: johnrobjr
author_rank: Newbie
timestamp: July 21, 2020, 05:39:26 pm
content: Hi Wuerstchenhund, and others too!I've got a MT8815A that powers up; but, it gives a "TDMCOM1" error.Do you know (or does anyone know) what a TDMCOM1 is?... I am just guessing its a subsystem/board/module in the MT8815A frame? TDM and COM1 refer to time domain communications?There is a list of "items" the MT8815A frame checks/self-checks, upon powering it up... and TDMCOM1 is the last item. (All the others pass)there is an associated number, "6200352829"After quickly passing through the other item, during self checking, it pauses on TDMCOM1, for about 45 seconds, and then the following error message is displayed:"System abnormal completion. Please push any panel key."Ya. So when I push any key, the MT8815A powers down.I have the user manual, but no service manual (can't find the service manual on the Web, or on R&S Website)The user manual does not tell me what a TDMCOM1 is, or what the error message means.I have not opened the MT8815A up, or otherwise done anything. I'm thinking that it is better to find out what the error message means, before opening it up.