Advice needed... Spectrum Analyzer purchase - Page 1
Forum section: electronics / testgear

author: jayk
author_rank: Regular Contributor
timestamp: February 14, 2020, 05:46:40 pm
content: I'm looking at getting my first SA. This will be for a combination of antenna testing, active and passive component measurement, oscillator characterization and maybe some signal demodulation. Would like to go up to at least 3GHz, spend under $3K and not end up with a massive 'boat anchor'-sized instrument. I've been looking a lot at Signalhound (SA44B or maybe a used BB60C + TG) and the lower-end Siglent SA and VNA (i.e. SSA30xx or SVA10xx). Anything else I should look at?

author: nctnico
author_rank: Super Contributor
timestamp: February 14, 2020, 06:11:06 pm
content: I think the Siglent is a good choice but I don't know if their VNA goes to 3GHz. Tautech will answer that shortly.I can highly recommend getting a VNA for work on antenna design because it is much easier to determine the compensation network from VNA data. A spectrum analyser + tracking generator is not very useful (which is probably why you'll find so few used spectrum analysers with a tracking generator). You can see an antenna isn't right but don't get a clue on what is wrong when using an SA+TG.

author: bob91343
author_rank: Super Contributor
timestamp: February 14, 2020, 07:06:34 pm
content: A tracking generator is VERY useful, and can be shut off if desired. If you aren't looking for laboratory precision,consider the nanoVNA. Mine has superseded the boat anchor units for most work.I own several SAs and VNAs but they really consume lots of space and are very heavy. Up to 1 GHz my old IFR does well.Consider used gear; the price difference is worth it.For ordinary ham radio work, the nano is more than adequate. And at $40 new it's a major bargain. Still, the big units certainly offer many features and wider bandwidth. The nano isn't that great a SA but for antennas and filters it's pretty good.

author: DaJMasta
author_rank: Super Contributor
timestamp: February 14, 2020, 07:14:17 pm
content: I think R&S's entry level SA also fits in that price bracket, but I don't know if the 3GHz variant with a TG fits there.Especially for your characterization work, a TG would be a big benefit.... and honestly if you want antenna testing, you probably want one port VNA measurement as well.Siglent's SVA offerings are an option, but I'd also look at a used Anritsu Cellmaster or Sitemaster. Though, technically speaking, a portable/handheld unit intended for field use, they are very sensitive and often can be found with a TG and/or single port vector measurements, sometimes with transmission measurement, all in a small package and likely in your budget. Their newer models may be pushing it, but I wouldn't be surprised if you could find a 4GHz model with the single port VNA measurements for that budget, or an older model 6/7GHz version.

author: tautech
author_rank: Super Contributor
timestamp: February 14, 2020, 07:43:08 pm
content: Quote from: jayk on February 14, 2020, 05:46:40 pmAs you probably know the 3.2 GHz SSA1032X is a touch over your budget @ $3410 but can do all you need and more. However pumping it full of options will set you back further but luckily options have 120 hrs free run time so you can get a few projects done before needing to buy the ones you need.When first released VNA was an option for SVA but now it's included in a higher base price and all SSA/SVA models come with TG option free.There is a 7.5 GHz model in development and I've seen a beta unit of one but of course that will be another jump up in price.I was where you are at a few years back when the SSA were released and I got the SSA3032X for a demo model and learnt the basics with it but when the SVA models were released I grabbed the SVA1015X too and wow they open up a whole further set of capabilities. Only SVA and the later SSA3kX Plus have the Modulation analysis option although any of them can demodulate into the headphones output.Good luck with your hunt and sing out if there's any other gaps of info needed.Oh and hunt out my Antenna Project Log to get an idea of what the SVA VNA mode can do.

author: Rich@RohdeScopesUSA
author_rank: Frequent Contributor
timestamp: February 14, 2020, 10:12:13 pm
content: While slightly above your $3k limit ($3,500), our FPC-COM1 bundle will give you our FPC1000 3GHz Spectrum Analyzer with Preamp, Modulation Analysis, Receiver Mode and Advanced Measurements.And at $5K, I realize it's way over, but the FPC-COM2 bundle has the FPC1500 @ 3GHz with all the same capabilities as the FPC1000, but also includes a TG, independent CW signal generator, built-in VSWR bridge and 1-port VNA.https://www.rohde-schwarz.com/us/product/fpc-productstartpage_63493-542324.htmlThere are also less fully optioned versions that are quite a bit cheaper (start at $1,880), but the value of the COM bundles is nice.Let me know if I can help on the R&S side.-Rich

author: uncle_bob
author_rank: Unknown
timestamp: February 24, 2020, 03:10:30 am
content: HiThe only thing that does not seem to have been tossed out yet is the Tektronix 306B. Like the FPC-COM2, it's a bit over budget depending on just where you find it. There was a 306 (with no B) that cost a bit less. Based on what I've heard so far, you would want the 306B.======One thing the FPC-COM2 gives you is the ability to run the tracking generator as a (CW only) signal generator. With something accurate driving the external reference input, I suspect you can generate a pretty stable signal. The Tek 306B and the Signal Hound's have a similar 10 MHz external reference setup. Not sure if they will let you run the tracking generator as a signal generator.=====There are indeed some very nice older spectrum analyzers on the used market. As long as they keep working the can do very well for you. Servicing one can once you get past "reseat all the boards" can be exciting. At least the ones I have here are pretty big and pretty heavy ......Bob

author: hendorog
author_rank: Super Contributor
timestamp: February 24, 2020, 04:03:38 am
content: Quote from: uncle_bob on February 24, 2020, 03:10:30 amI don't think there is a tracking gen available for the 306?Quote from: uncle_bob on February 24, 2020, 03:10:30 amThe Signalhound TG can be used on its own, but it's really not very good in that role. It relies on the SA filtering and has quite poor phase noise. Better than nothing thoughI think the OP is going to be choosing between the Signalhound combo and the SVA1032X:SH is the lowest cost SA+TG, but has some compromises. OTOH the SVA is more capable as an SA, and of course it has the VNA feature included.

author: james_s
author_rank: Super Contributor
timestamp: February 24, 2020, 04:16:43 am
content: What about the venerable HP8594E? The 859x was the gold standard in the broadcast industry and a good tested working one with the optional tracking generator should be under $2k. It's not a cutting edge lunchbox but I'd hardly call it a boatanchor either. It's a fully self contained instrument about the size of a CRO though quite a bit heavier, very rugged and designed for field use. I have one without a TG and have been really happy with it. A TG would be nice but those without are quite a bit cheaper and easier to find.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: February 24, 2020, 07:56:53 am
content: Have a look at the GenComm GC700A (later sold as JDSU JD700A) portable test sets. These are compact RF test sets which contain a Spectrum Analyzer, a Signal Analyzer, a VNA portion (which also measures phase), a RF generator (CW only, though) and an internal Power Meter.The GC740A Series covers 10MHz to 4GHz and can often be found below $3k. There are 8GHz models, too (GC780A Series) but they usually go for notably more.The RF performance isn't stellar but in the ballpark of what's common for entry-level SAs. They also don't need much space on the bench, have a nice big XGA display (which has a daylight mode for outdoor use), and they can be battery operated (they are great for transmitter hunting as you can load a map from Google Maps into the instrument and use it to find transmitters through triangulation).Note that not all models have all features (SA, VNA, RF gen and power meter were options) so make the instrument you consider has the options you want.Until recently I had a GC747A which had all the options, I used it a lot for many simpler tasks despite having access to more advanced spectrum analyzers.As a first SA for hobbyist purposes this could be a great device.

author: uncle_bob
author_rank: Unknown
timestamp: February 24, 2020, 02:35:04 pm
content: Quote from: hendorog on February 24, 2020, 04:03:38 amHiYup, the third connector on the front of the 306 throws me off. It's for trigger rather than a tracking generator. To get the TG, you need to move up in the lineup and that gets crazy expensive.Bob

author: jayk
author_rank: Regular Contributor
timestamp: March 01, 2020, 03:51:19 am
content: Quote from: Wuerstchenhund on February 24, 2020, 07:56:53 amI've been researching the GC700 series you recommended. Seems like a decent value in the $1-2K price range, but it's hard to sort out the options - the ebay listings are hard to correlate again the data sheet. Lots of cellular-specific stuff in there obviously.Does it have some VNA capabilities? I thought I saw a mention of being able to make S11 and S21 phase measurements.Why did you get rid of yours? Did you replace it with another SA?

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: March 01, 2020, 09:43:08 pm
content: Quote from: jayk on March 01, 2020, 03:51:19 amThere are various models (RF Analyzer, Base Station Analyzer, LTE Analyzer) which differ in what comes as standard but at the end of the day the cellular stuff is only important if you are working with cellular equipment. If not then it doesn't matter what cell standards it supports.From what I remember the GC747A (LTE Analyzer) was the best equipped model which had most options (SA. VNA/CAA) as standard, and it also supported all the interesting option. What it didn't have is support for any other cellular technology than LTE.QuoteYes, it has. Pretty much the same as the Siglent SVA and the other entry level VNAs offer.QuoteBecause I have a client who cheekily talk me into selling it to himDue to some personal changes I don't have a lot of time for hooby stuff, and at work I have access to some of the best high end VNAs ever made, so seeing it going to someone who has a lot more use for it was a supporting factorThe new owner uses it for EMC pre-compliance tests and seems to be very happy with it.