Best USB stick/device as Spectrum Analyzer for <= US$ 500

[G0HZU]

Wowowowoow....never thought I start a discussion like that....(o;

But great forum and members here to read all their opinions and suggestions :-)

Nevertheless I will start with the SA44B...as I get a new device for Euro 799.....
I've also looked on ebay for along time for real SAs...but they are still too bloody expensive or just too old...

I see the Signalhound as a starting device for me being a hobbyist...well...in the RF area....and maybe this device will help me to understand this new field better...and even build own devices above 1MHz (o;

So far my field is only embedded hardware/software design and FPGA synthesis as well as PCB design....

Most users appear to be quite content with the SA44 now that there is a new suite of SW to control it. So I expect you will be OK

[_Wim_]

Don't hold your breath. If that works like similar discussions in the past then you might hear about some incredible deals by certain individuals, but unless you're at the right time at the right place and know the right people, these bargains of cheap high quality test gear for bottom basement prices are unlikely to materialize for the majority of people. That (as you probably found out already) mostly leaves the stuff you find on ebay & co., which in the lower price range usually consists of "untested" (i.e. guaranteed to be defective) or openly defective bangers from 25yrs ago, and even if you spend more you'll mostly get either some 20+yr old standalone SA (often the 75ohms variant) or working but spec-wise not perfect comms testers like the mentioned CRTU.

SAs are pretty expensive, even used ones, and the smaller your budget is the larger the limitations (specs, age and therefore reliability, size, noise, features) you have to accept.

Wuerstchenhund posted the in my opinion the best available deal so far, but I am still doubting because of the following reasons:
-   Price is more then 500€
-   Looks a very complex unit for an RF-beginner like my…

I wouldn't worry about complexity, especially since any other SA will very likely be even more complex. The advantage of newer kit like the CRTU is that it is much more reliable than kit from 25+yrs ago, there's not much that needs adjustment, and thanks to the modular design repairs are pretty easy (and modules can often be found on ebay).

Should you decide for a CRTU then offer EUR500 (and tell him that you know that the market is going to be swamped with these things), which I'm sure a sensible seller would gladly accept, considering that these things will only fall in value.

Thanks, I will give that a try, and if the seller does not accept, I will include the CRTU in all my future ebay-searches

[Wuerstchenhund]

Thanks, I will give that a try, and if the seller does not accept, I will include the CRTU in all my future ebay-searches

You could also try to ask for offers in the Buy & Sell section of this forum, as it seems a few forum members have bought several CRTUs from the recent auction in Finland, and by now are probably ready to sell some of their boxes on, and saves them the ever increasing ebay fees (so you might get a CRTU for even less than EUR500).

BTW, should you buy one it would be great if you'd come back and report about your experience with the CRTU, as I'm sure this could help other beginners looking for a similar low-budget entry into RF.

Also, don't forget to buy some proper RF cables and adapters. I'd avoid the noname China stuff and go for reputable brands (like Gore, Huber & Suhner, Amphenol etc) instead. Doesn't have to be expensive, brand name RF cables regularly can be found on ebay for little money.

[davorin]

I did both now...ordered a Signalhound SA44B with some adapters as also posted on the buy/sell forum if someone has a spare CRTU (o;

The SA44B should arrive already on Friday or Monday as it is on stock in Netherland....

[davorin]

So both are on the way...SA44B and CRTU (o;

BTW: Anyone seen a service manual and operating manual for the CRTU? Especially interested in remote programming.

[Wuerstchenhund]

So both are on the way...SA44B and CRTU (o;

Nice. So you could do some comparison 

BTW: Anyone seen a service manual and operating manual for the CRTU? Especially interested in remote programming.

All documentation (including Operating Manual, Quick Start Guide and Service Manual) should be in the Windows 2000 partition.

[davorin]

Well sure I will compare them and post some pictures (o;

Ah okay...and I assume the CMU200 service manual has some analogies to the CRTU as the CRTU is just a CMU200 with Win2K in the box...

Also I read in another thread that the Win2k software is mainly for automated testing...but measurements can be done from within DOS....
so basically it would be possible to drop Win2k completely and have it replaced with Linux? (just my wishful thinking ;o)

[Wuerstchenhund]

Well sure I will compare them and post some pictures (o;

Ah okay...and I assume the CMU200 service manual has some analogies to the CRTU as the CRTU is just a CMU200 with Win2K in the box...

Not quite. There are some hardware differences as well.

Also I read in another thread that the Win2k software is mainly for automated testing...but measurements can be done from within DOS....
so basically it would be possible to drop Win2k completely and have it replaced with Linux? (just my wishful thinking ;o)

No, unless you write all the Linux hardware drivers for the various DSPs and proprietary signal processors yourself.

What you could do is however to write your own Windows software, considering that the W2k partition already comes with the hardware drivers, and also with Microsoft Visual C++.

[davorin]

Just picked up my CRTU from post office and fired it up...Amazing device with loads of buttons and connectors (o;

Guess I have to do some heavy manual reading to get to know it....but at least it prompts to the RF spectrum display when powering up...

[Wuerstchenhund]

Just picked up my CRTU from post office and fired it up...Amazing device with loads of buttons and connectors (o;

Guess I have to do some heavy manual reading to get to know it....but at least it prompts to the RF spectrum display when powering up...

Don't worry, once you get around the somewhat quirky way R&S designs their UIs it's pretty easy to use. But don't rely on teh CRTU documentation as this mostly only covers the automated testing under Windows. Just read the CMU200 manual and you'll see how things work for manual testing.

But the first thing I'd do is a full backup of the hard disk, as the disks in these devices quite often start getting bad sectors these days. Once you've a backup then you can just swap it for a new drive, or a SSD.

[davorin]

What is the best way to do a backup? Install some backup software under Win2k?
Or can I boot with some Linux USB stick with a backup tool?

I see 3 partitions inside C, D and E...

Definitively I will replace the drive anyway with a SSD soon...

Does RAM upgrade bring some improvements as well?


BTW: What was the original price of this device?

[Wuerstchenhund]

What is the best way to do a backup? Install some backup software under Win2k?
Or can I boot with some Linux USB stick with a backup tool?

Yes, you can boot from a Linux USB stick (you might need an external monitor if the Linux tries to switch to a higher resolution than 640x480@60Hz).

I see 3 partitions inside C, D and E...

Definitively I will replace the drive anyway with a SSD soon...

Does RAM upgrade bring some improvements as well?

RAM upgrade won't bring much, at least not under DOS. If you plan to use the W2k partition then that's adifferent story, though. The FMR6 controller in the CRTU takes SODIMMs btw (PC133 SDRAM), but I'm not sure it supports 512MB modules.

The SSD is a great update, I put a Transcend PSD330 in mine, which is quite noticable under W2k.

BTW: What was the original price of this device?

Difficult to say but depending on the config somewhere between $100k and $180k.

[davorin]

Just browsed through the documentation on the harddrive...

Seems though the CRTU has a GPIB connector, it is not meant for controlling it, but the CRTU controls other devices....

Is there no way controlling this device remotely to set start/stop/span rbw and so on and having a screen dump created?

[Wuerstchenhund]

Just browsed through the documentation on the harddrive...

Seems though the CRTU has a GPIB connector, it is not meant for controlling it, but the CRTU controls other devices....

Is there no way controlling this device remotely to set start/stop/span rbw and so on and having a screen dump created?

Under Windows, the CRTU can act as GPIB controller or be remote-controlled by another device via GPIB. Under DOS, the CRTU can only be controlled via GPIB but not act as a controller itself.

You can also control the CRTU via RS232 (DOS only), or via LAN (Windows only).

[davorin]

Hmm...didn't saw anything in the documentation how to control the CRTU via GPIB...

Also...didn't respond to *IDN? query to the preset address under DOS...well..tried under Linux with "ibterm" and a S82357 USB adapter...

Is there no GPIB/SCPI programming manual like HP supplies?

[Wuerstchenhund]

Hmm...didn't saw anything in the documentation how to control the CRTU via GPIB...

Also...didn't respond to *IDN? query to the preset address under DOS...well..tried under Linux with "ibterm" and a S82357 USB adapter...

Have you checked the GPIB settings in the CRTU's software?

Is there no GPIB/SCPI programming manual like HP supplies?

If you want to control it in DOS mode then you'd have to look in the CMU200 manuals, as the CRTU manuals mostly discuss the Windows software.

[davorin]

Yes I checked it...default set to GPIB address 20....not sure what the slave address is good for....as they can be set for RF generator and different GSM modes...

Ah right...the CMU200 is similar....but as I've read the CMU misses the spectrum analyzer? So those commands would be missing?

Anyway...already late here in .ch...downloaded the operating manual and will read through tomorrow (o;

[Wuerstchenhund]

Ah right...the CMU200 is similar....but as I've read the CMU misses the spectrum analyzer? So those commands would be missing?

No, the CMU200 also does have the spectrum analyzer. In fact, the DOS software between CMU and CRTU is identical.

[davorin]

Ah great to know....

Does R&S supply software/firmware updates for everyone or only through expensive support contract?

Well...from the software point of view I intend to use the DOS version only....meaning the RF spectrum application....
And if that's controllable remotely...than it's a perfect device...

Not sure for what the TCP/IP setting is for...guess that's for the TFP automation only?

[Wuerstchenhund]

Ah great to know....

Does R&S supply software/firmware updates for everyone or only through expensive support contract?

You need an R&S GLORIS support account, with access to the CMU and CRTU areas, which is usually only provided to corporate customers.

This is because access to firmware and compatibility module updates was regulated by support contracts.

What version of the DOS software do you have (you can check in Version Manager, which you can get into by pressing a button during the loading phase when the CRTU splash screen is shown).

Well...from the software point of view I intend to use the DOS version only....meaning the RF spectrum application....
And if that's controllable remotely...than it's a perfect device...

It's remote controllable via GPIB and serial.

Not sure for what the TCP/IP setting is for...guess that's for the TFP automation only?

The TCP/IP settings in the DOS application are for data transfers between a cell phone and an external server. This was used to test data transmission (i.e. mobile internet).

Unfortunately the DOS application can't be controlled via network.

[davorin]

It says software version 4.34...

Took me a while as I was recabling my whole lab (o;

[davorin]

Hmm...still no joy with GPIB and F82357 with linux-gpib...

Not even answers to a simple *IDN? query....

[jadew]

Congrats on the new acquisition!

Any preliminary impressions on it?

[davorin]

Apart from the fact I can't control it with GPIB....I'm really happy....

Well...my main focus was to get a reasonable USB spectrum analyzer...

I just played a little with the RF spectrum analyzer...not much more....people mentioned that it is not a perfect SA like a clumsy HP or any dedicated SA:..
But it does sweeps really fast from 10MHz to 2.7GHz.

It looks like almost unused...nice equipment...now the Fluke 606A/AN looks like stone-age in design...but that one gets replaced soon with a R&S signal generator (o;

[Mr Simpleton]

Have you received the SA44 yet? I am eagerly awaiting your put up against the CRTU