Anritsu MS8609A 9kHz - 13.2GHz Spectrum/Signal Analyzer - Short Review

[Wuerstchenhund]

For a while now I felt that I wanted more bandwidth than my trusty R&S FSP 7 could provide, plus I wanted some I/Q analysis capabilities (which the FSP doesn't have), so I went on the search for a 2nd hand SA with a bandwidth of at least 12GHz and decent RF performance. If that new SA came with a less onerous UI then even better.

I didn't need a Tracking Generator as I rather use a wideband noise source (TGs usually come with a hefty premium, and often don't even cover the whole SA bandwidth). I also didn't want something which is 30yrs old, overly large, or which comes with a CRT display. It should be a modern, somewhat compact, low maintenance device.

Capable Agilents (PSA) were way out of my price range. The R&S FSIQ was a contender, but especially the high BW models are expensive, and it comes with the same cumbersome UI as the FSP. So I was contemplating on the alternatives. Advantest had the R3477, but at the time I had been looking asking prices were in the $3k+ range (and it seems they are back there again), and frankly I was never a big fan of some aspects of Advantest's build quality.

I then looked at Anritsu. It's T&M division is pretty much an RF centric company that makes gear which is predominantly used in the telecoms industry. Anritsu kit also has an excellent reputation in terms of reliability and maturity. However, this time I didn't want a simple cell phone tester, so I had a look at Anritu's standalone SAs. After some searching I found a MS8609A Transmitter Tester, a spectrum/signal analyzer sold for testing cell phone tower and other transmitters, with a frequency range of 9kHz to 13.2GHz. All for some $900 (plus shipping and VAT/Customs, but still).

The following is a short review of that MS8609A.

[Wuerstchenhund]

Anritsu is a Japanese manufacturer of T&M gear. It was founded in 1895 as Sekisan-sha so it has been around for a very long time. Anritsu pretty much focusses on gear for RF and optical communications, and its main target is the telecoms industry (cell phone service providers).

Anritsu uses a common nomenclature for its test gear, which consists of a prefix (Mx) followed by a four or five digit product number. The 'M' in the prefix stands for Measurement Division, the second letter determines the product category (i.e. 'T'='Test Set', 'S'='Spectrum Analyzers', 'G'='Generators', 'L'='Level meters', 'P'='Photonics').

For someone looking to look at RF spectra, there are two options, MT and MS.

The MT Series contains integrated cell phone test sets of which many of the older ones (i.e. MT8801A, MT8820A) are used by hobbyists as inexpensive Spectrum Analyzer and RF generator. As with many cell phone test sets, the RF performance is pretty limited, which is why the Spectrum Analyzer in these devices is called a 'Spectrum Monitor'.

Anritsu's 'real' lab-grade Spectrum Analyzers carry the 'MS' prefix. 'MS' is also used for derivative products that are based on the standalone SA models, like the MS860xA Transmitter Test Sets which are covered in this short review.

While Anritsu offers test sets under both the 'MT' and 'MS' prefix, as the 'MS' is based on 'true' lab-grade SAs its performance is notably better than the 'MT' Series test sets, by a pretty large margin.

[Wuerstchenhund]

The MS8609A Transmitter Test Set is a spectrum/signal analyzer based on the MS268xA Series of standalone Spectrum Analyzers. The MS860xA family has two members, the MS8609A with a bandwidth of 13.2Ghz and the MS8608A with a bandwidth of 7.8GHz.

The MS860xA was introduced in I believe 2004 as Anritsu's alternative to Agilent's E4406A VSA Transmitter Tester, and remained in production until early 2013. However, while the Agilent VSA (which is based on the Agilent PSA Series of Spectrum Analyzers) was a very limited device (max 10Mhz span, 100MHz with W-CDMA/HSDPA option, FFT operation only), the MS860xA retained mostly the same functionality and performance as Anritsu's standalone lab-grade Spectrum Analyzer Series MS268xA. The differences between Transmitter Test Set and Spectrum Analyzer models, aside from frequency range (the MS268xA maxes out at 7.8GHz), are limited to the absence of the Tracking Generator option on the TX Test Set and some front panel connectors (the MS860xA comes with balanced and unbalanced I/Q inputs; the MS8608A also has an additional low power input which is not found on the MS8609A).





Performance Specifications

The baseline specs of the MS8609A are:

- Frequency range: 9kHz to 13.2GHz
- Span: 0Hz, 5kHz to 13.2GHz (+1%)
- RBW: 300Hz to 20MHz (Option 02 Narrow Resolution Bandwidths: 1Hz to 1kHz | option 04 Digital Resolution Bandwidths: 10Hz to 1MHz)
- VBW: 1Hz to 3MHz, off
- Detection modes: Normal, Positive, Negative, Sample, Average, RMS (option 04 Digital Resolution Bandwidths)
- Sweep time: 10ms to 1000s (frequency domain), 1us to 1000s (time domain)
- Sweep refresh rate: >20 traces/s
- No of data points: 501, 1001
- Max input level: +20dBm
- Input attenuator: 0dB - 62dB (2dB steps)
- DANL: -146dBm/Hz (1MHz to 2.5GHz)
- 1dB gain compression: +3dBm (+10dBm typ, >500MHz)
- Level accuracy: +0.75dB (+0.1 to 20dBm), +0.5dB (-49.9 to 0dBm), +1.5dB (-80 to -70dBm)
- Phase noise: <-108dBc/Hz (1Ghz, 10kHz offset), <-120dBc/Hz (1Ghz, 100kHz offset)
- 2nd harmonic distortion: <-60dBc (10-200MHz), <-75dBc (200 to 850MHz), <-70dBc (850MHz to 1.6GHz), <-90dBc (1.6 to 6.6GHz)
- 2-tone TOI distortion: <-85dBc (0.1Ghz to 3.2Ghz)
- Residual response: <-100dBm (1Mhz to 3.2GHz, Band 0), <-90dBm (3.15Ghz to 7.8Ghz, Band 1)

The performance specs for the MS8608A are identical, aside from the lower bandwidth (7.8Ghz instead of 13.2GHz).

It should be remembered that, despite being sold as 'Transmitter Tester', the MS860xA is still a true lab-grade Spectrum Analyzer and not just a test set with tacked-on spectrum monitor functionality, like the MT88xx Series of cell phone testers. It's RF performance is identical to the MS268xA standalone Spectrum Analyzers.


The MS8609A Hardware

The SA is somewhat compact (320mm x 177mm x 411mm) but at approx 16kg it's not exactly a lightweight. The overall construction is rock solid as one would expect from Anritsu.

The front is covered with the typical standard set of buttons.


MS8609A Front Panel

Aside from the RF input (N) there are also balanced and unbalaned I/Q inputs. Unfortunately the input is DC sensitive which means an external DC block should be used to protect the input. The display is a bright 6.5" VGA (640x480) TFT with good viewing angles. The display brightness can be adjusted in the settings, and while it doesn't have a time-out it can be easily switched off by a button located to the left of the display.


MS8609 Display


Below the display is a PCMCIA slot which can take Compact Flash cards via CF-to-PCMCIA adapters to store screenshots (BMP), measurement data and settings. Firmware/software updates can also be performed through it.

I haven't opened my MS8609A yet as it still has the Anritsu seals in place and there was no need to break them, so in the absence of a Service Manual I can't say what platform the system is built on (although it's obviously no PC/Windows platform). My suspicion is that it's based on something like VxWorks on some embedded PowerPC platform. It also does boot pretty fast (7s?).

On the rear there are various connectors for external Reference In/Out, IF Out and Wideband IF Out, Sweep and Video, as well as obligatory GPIB, VGA, Ethernet (Option), serial and parallel connectors.


MS8609A Rear Panel


The instrument is cooled by a large 120mm fan in the back hump which isn't exactly silent, and when the device is in standby then this fan is off but one can hear a another, apparently much smaller standby fan which I guess is used for the Stby PSU. The overall noise isn't excessive but I'd still consider it loud. Unfortunately without having seen the inside it's impossible to check if the noise level can be improved (which I guess it can, as the air the large fan pushes out is barely warm).

Like with many similar instruments, there are several hardware options available for the MS860xA:

- Option 01 - Precision Frequency Reference: Rubidium reference)
- Option 02 - Narrow Resolution Bandwidths (FFT): FFT based narrow resolution RBWs from 1Hz to 1Khz in 1-3 sequence)
- Option 04 - Digital Resolution Bandwidths: RBWs from 10Hz to 1MHz and RMS detector
- Option 08 - Pre-amplifier: switchable pre-amp with 20dB gain
- Option 09 - Ethernet Interface: enables the built-in network port
- Option 30 - LPF for 2GHz Band Carrier Cut
- Option 31 - Low Noise Floor
- Option 32 - Maximum Input Level Extension: extends max input to +30dBm
- Option 33 - High Accuracy Power Measurement
- Option 34 - 4GHz LO Output
- Option 36 - Power Meter Hi Limit Frequency Expansion (6Ghz)
- Option 37 - same as Otion 36 but as retrofit option
- Option 46 - Auto-Power Recovery: disables power switch, on/off performed with stby switch on the rear
- Option 47/48 - Rack Mount

The MS8609A I bought came with options 04, 08, 31 and 47. As I have no use for a rack-mount unit I removed the rack-mount frame and retrofitted the carrying handle, which is missing on rack-mount units.

While some of the options certainly require the installation of additional hardware (i.e. the Rb Reference), others like 02 (Narrow Resolution BW) or 09 (Network interface) shouldn't as the hardware should already be in the instrument. My guess is that these options are just software-locked.


MS8609A Installed/Enabled Hardware Options

[Wuerstchenhund]

Software and Operation

The MS8609A offers two operating modes, Spectrum Analyzer ('Spectrum') and Transmitter Tester ('TX Tester'). 'Spectrum' is self-explanatory, and 'TX Tester' contains Modulation Analysis for several modern wireless standards (there's no AM/FM demodulation, though) and Power Measurements. Switching between both modes is done by a simple press of the corresponding front panel button. When switching modes the settings of the exiting mode are memorized so switching to a different mode doesn't let pre-made settings disappear.

Operation of the Spectrum Analyzer is very easy as all functions are either directly available or can be found in the simple menu system. Primary parameters like start/stop frequency, center frequency, span and reference level have their dedicated buttons. In default mode, Attenuator, Sweep Time, RBW and VBW are set automatically in accordance with the frequency span, but each of them can also be set manually.

Setting a marker to the peak signal or setting the peak signal as center frequency can also be done by a single button press. The MS8609A also supports zone markers and multi-marker (up to 10) which can be assigned manually or automatic (by peaks or by harmonics). It also offers various measurements, including Occupied Bandwidth (OBW) or Signal/Noise (in dBc/Hz or dBc/ch).

Screenshots (BMP format), measurement data (CSV format) and settings can be stored on removable storage in the front PCMCIA slot. I'm using a 512MB Compact Flash card in a CF-to-PCMCIA adapter which works fine.



TX Tester and Software Options

In regard to software, since the MS860xA is based on a standalone Spectrum Analyzer, the 'Spectrum' functionality is part of the Core software. However, Anristu offers additional analysis packages for various wireless standards that can be installed, and which can then be found in the 'TX Tester' mode.

The available software options are:

- MX860901B - W-CDMA Measurement Software
- MX860902A - GSM Measurement Software
- MX860903A - cdma Measurement Software
- MX860904A - CDMA2000 1xEV-DO Measurement Software
- MX860905A - Pi/4DQPSK Measurement Software
- MX860920A - BER/BLER Measurement Software (requires MU860920A Demodulation unit)
- MX860930A - Wireless LAN Measurement Software
- MX860950A - HSDPA Measurement Software
- MX860951A - W-CDMA Release5 Uplink Measurement Software
- MX860960A - TD-SCDMA Measurement Software

Each option contains a separate software package that needs to be installed on the instrument (i.e. via CF card and CF-to-PCMCIA adapter). While any number of options can be enabled, the instrument can only hold 3 option packages. If another package is needed then one needs to be erased from the instrument to make space for the new package.




Software packages can't be installed if the coresponding option has not been enabled on the device. How these options get enabled in the first place, I don't know. There are no (end-user visible) facilities to enter product keys.




My MS8609A came with the W-CDMA option. It allows a wide range of measurements, i.e. constellation display, eye diagram, EVM diagram, Phase Error Display, and Magnitude Error Display. For example:

[Wuerstchenhund]

I didn't had much time to do a lot with the MS8609A, however here are some simple examples of a few basic measurements.

Here is a simple CW signal from my RF generator connected via a less than perfect wonky BNC cable:




The next example show Phase Noise measurements (C/N₀):












The last example shows a simulated 802.11a WiFi signal sourced from an Anritsu MG3700A Vector Signal Generator, in Frequency Domain, Time Domain, and Frequency/Time Domain Split Screen:










This is far from a comprehensive test of course, which would take a lot more time, especially when including the various modulation analysis tools.

[Wuerstchenhund]

Clearly this wasn't a thorough review (for which I neither have the time nor the equipment), and in terms of capabilities or RF limitations I haven't even scratched the surface.

Still, from what I see, the Anritsu MS8609A is a very capable instrument (and that is very likely true for it's lower bandwidth sybling MS8608A as well!). It's RF performance is vastly better than what can be found with the current crop of new B-brand SAs, all of which also usually have a limited RBW of 5Mhz or even less. The MS8609A also didn't exhibit any firmware problems, and seems to be as reliable as one would expect from a premier brand like Anritsu.

The MS8609A's main disadvantages are the absence of a TG, the somewhat noisy fan, and the lack of a Service Manual (although I guess sooner or later one will be leaked somewhere somehow). Not that the situation re Service Manual is any better with most B-brands.

At the moment of writing used MS8608A and MS8609A can often be found in the sub-$1500 price range (I paid some $900 for my 2012 MS8609A which, thanks to being used in a rack environment, literally looks like new), which makes them hard to beat for anyone who's after a serious Spectrum Analyzer with decent bandwidth.


Pros:

+ Up to 20MHz RBW makes it great for newer wideband signals (i.e. 802.11b/g/n WiFi)
+ Good RF performance
+ Fast processing
+ Wide range of measurements and analysis functions (option dependent)
+ Still somewhat compact size
+ Typical Anritsu build quality (i.e. it's a tank)


Cons:

- RF input DC sensitive
- No Tracking Generator (although this could be substituted by a wideband noise source)
- No direct AM/FM modulation measurements
- Ethernet as option only
- Relative loud (but there's a chance that this could be improved)
- No Service Manual available (yet?)
- No unlocking/hacking to enable more options (yet?)



Attachment: Anritsu MS8609A Product Introduction

[nctnico]

I'd put 'no save to USB stick' under the cons too unless I missed it.
Edit: and how about LAN?

[Muxr]

Nice piece of kit.. would love to see some measurements, to see what the UI looks like.

[Howardlong]

Nice, but I'd sure like to know where these things turn up for $900.

[Wuerstchenhund]

I'd put 'no save to USB stick' under the cons too unless I missed it.
Edit: and how about LAN?

As the title says this was WORK IN PROGRESS so stuff was still done to the review. I added LAN as an option as a negative (at least until someone finds out how to hack it). As to USB sticks, I'm not sure that using CF card is really a disadvantage as any PC with a media card reader can read them, plus they are a lot more reliable than USB sticks (plus many instruments that support USB sticks only work reliably with certain brands or size limitations).

Nice piece of kit.. would love to see some measurements, to see what the UI looks like.

Some measurements have been added. If you want to see more from the UI then I can post more pictures.

One thing I didn't mention in the review is that the UI color scheme can be changed to some predefined themes (which also include a 'green CRT' style theme) as well as user defined schemes.

Nice, but I'd sure like to know where these things turn up for $900.

Ebay 

[Muxr]

Thanks for the [mini]review Wuerstchenhund! Nice alternative for folks looking for [affordable] yet capable SAs.

[Howardlong]

Nice, but I'd sure like to know where these things turn up for $900.

Ebay 

Lucky fella!

[Wuerstchenhund]

Nice, but I'd sure like to know where these things turn up for $900.

Ebay 

Lucky fella!

I don't know, it's certainly a good deal but far from being a 'once in a lifetime' thing. Especially with stuff that is obscurely labelled (like 'Transmitter Test Set' instead of 'Spectrum Analyzer') you can often negotiate with sellers much better than for commonly known items.

[voxadam]

Sorry to raise this post from the dead but I came across a couple of MS8609A units and in the absence of a service manual I'm curious if anyone has cracked one open to see what makes them tick.

[Wuerstchenhund]

Sorry to raise this post from the dead but I came across a couple of MS8609A units and in the absence of a service manual I'm curious if anyone has cracked one open to see what makes them tick.

I haven't opened mine as it's still sealed from factory, but I replaced the rear fan and could peek inside when the fan was out. It appeared to be a relative service friendly design.

Should you decide to open one please make some pictures. Also, I'm very curious about enabling the Ethernet port, i.e. if it's just a software code or if enabling requires additional hardware (i.e. a NIC board) that is not present on non-networked instruments.

As to the Service Manual, I asked Anritsu UK for it a few times but they say they don't give that out. Anritsu does offer service manuals for other (older) gear, though, so it may be worth asking Anritsu dependencies in other countries, maybe they are a bit more flexible. Well, they should be when other companies like Keysight offer service manuals for their gear for download.

I also wonder how difficult it would be to hack the firmware to enable software options that are currently not enabled.

[eevcandies]

There seems to be a recent surge in these units being available....maybe some large corp is finally getting rid/upgrading a bunch at different locations.
I bit the bullet when I found one with the rubidium atomic timebase (it is option 5). Of course that is slightly riskier than an ovenized xtal.  Overall, the installs looked good:
Opt04 Digital resolution BW (RBW 10Hz)
Opt05 Rubiduim clock (1x10e-10/mo)
Opt08 Pre-Amp (100KHz-3GHz+20 dB, NF=6.5 typ)
Opt31 Low Noise Floor (-112dBm in 7.7-13.2 GHz band)
Opt32 Max Input Range Extension  (to +30 dBm, ref:-100 to +40 dBm)
cdma & other packages I didn't care much about
It arrived in flawless shape, like it just came from the factory.  In fact, to my surprise, it came with a full 9 pages of rather recent cal/test certification from Agilent/Keysight...all passing dead-nuts-center..I think it just sat around after being cal'd.
I thought that was a pretty good deal.
  I sorta wish it had option02  (narrowband res down to 1Hz), but that's just for messin around.

[YU7C]

I found one on ebay with about 11 years of Live Time Counter!

Otherwise it looks in excellent condition.

[eevcandies]

The one I got had exactly 2 years use on it & is in mint condition, not the slightest scratch or mark, even has a cover & is warranted ....
Seemed pretty good for about $1450...maybe I could have gotten it for $1200, or even less.  I might have overpaid somewhat, but I wanted one that was decent, not a bang-up job missing half the knobs.  With the Agilent cal included, I'm pretty pleased.

Now what do I do with my 8GHz analyzer?..guess everyone needs a backup or a collection

[Mechatrommer]

i made offer $1000 on the 11 yrs unit and the seller accepted it i was on 50 50 due to budget, i could wish the seller will decline it or raise the offer, so then i can ignore him or wait until i think and firm with the decision 100 times. now who's i'm going to blame? the review is tempting, the low noise floor and phase noise measurement not available on my decaying Advantest R3465 that i dont have time yet to fix.

[YU7C]

Usually, on such occasions, I put an insanely low offer, with a thought: "I tried and it didn't work".
But it worked a couple of times.

Good luck!

[Mechatrommer]

that is an insanely low offer. it was listed $1800, so i offered almost half of it. i guess some sellers put the price twice from what they expected. for some other sellers, you just offer $100-200 cheaper and they will quickly decline it. having hunting for SA in ebay for years, $1000 for a working 13.2GHz SA is shear luck, even on older phosphored CRT brand like Agilent/HP, so i dont know, if this Aritsu still has some life in it, it should be still a good deal, i quickly searched in google for damaged Anritsu unit before making an offer, so far not much hit, hopefully this thing is built like tank.

[YU7C]

Occasionally, I check situation na ebay about MS8609A, and I would like to buy it, but honestly, I don't have job for it. Most my Designs are digital.

Anyway, I already have: MS2601A, E4406A, E7495B, CMU200 and MT8801A. Time for selling?

[Mechatrommer]

if an equipment must have a job, i should have nothing. this is newbie wants to learn at limited budget. during kid time, i'm unable to learn, where to get money to buy stuffs? even china DMM is unaffordable. and my dad always into agriculture and preparing shelter for us, if ask him about electronics, he doesnt even know what a resistor is, even i didnt have a clue what a SA is until recently.

[eevcandies]

hopefully this thing is built like tank.
Oh it is very very well built.....exercise before you pick it up! 

I like mine so much, I'm almost (insanely) tempted to get another..but I must remain sane.
I wish the LCD was slightly bigger, but that is just me...I saw one of their other models lets you use the full screen for the wave (clears the menus out), but I don't think this unit can do so (or I just don't know how).  Can that be done on this unit?  There is a VGA video connector around back...might look good on my 20" monitor!

[Mechatrommer]

hopefully this thing is built like tank.
Oh it is very very well built.....exercise before you pick it up!

i mean the quality and durability of the little little tiny RF components inside, not by its weight. if its so, i've done my exercise on Advantest R3465, LeCroy WaveMaster/Pro, Tek 714, those are around 40 pounders middleweight class. at age of 40+, the trick to keep going is Glucosamine + Chondroitin + MSM, mainly due to 24/7 sitting for decades in front of a PC... i think my body developed stronger L shape posture but poorer I shape posture (standing straight)