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Products => Test Equipment => Topic started by: kberlen on May 05, 2014, 08:53:11 pm

Title: Spectrum Analyzer/TG purchase decision
Post by: kberlen on May 05, 2014, 08:53:11 pm
I am a newbie here, and really appreciate this  forum/site. I have been a professional RF tech for 35 years, and am looking to replace an aging spectrum analyzer. I would like for the "new" unit to have a tracking generator as well. Budget is $1500-$2500 dollars. Currently I am working as a contract broadcast engineer, and am trying to decide between a new Rigol DSA-815TG with the VB1020 bridge, or a used HP/Agilent/Tek unit. I have seen multiple reviews of the Rigol unit, but they seems to be confined to a bench or lab type setup. I will be using this unit at transmitter sites aligning 950MHz RF paths, sweeping antennas, and looking at satellite L-Band for dish alignment/troubleshooting.  Typically, these sites have high ambient RF levels. I am concerned about the performance of he Rigol unit in these conditions. The three year warranty is a big plus, as is the physical size, but need a unit that will work well at sites with high RF levels.  Any thoughts/feedback would be appreciated. Thanks.
Title: Re: Spectrum Analyzer/TG purchase decision
Post by: hammy on May 05, 2014, 09:48:15 pm
... decide between a new Rigol DSA-815TG with the VB1020 bridge ...

You can alternatively use the Mini Circuits Coupler "ZFDC-20-5+". Much cheaper, works also perfectly with the VSWR option.

Cheers
hammy
Title: Re: Spectrum Analyzer/TG purchase decision
Post by: Methodical on May 06, 2014, 12:18:12 am
Consider picking up an anritsu Sitemaster 332B off ebay.  You get all that and Distance-to-fault, which is freaking awesome even to play around with.  Also, no external VSWR bridge required and nice and portable.  On the other hand, the spectrum analyzer isn't nearly as good as the rigol.  Last I used a sitemaster I recall a pretty high noise floor.  If you need to certify something, I'm not sure if it'd work well for that.  I've got a LPC-3000 that I use as a precision analyzer.

The units themselves are pretty dated. The 332D (color screen) or 332E (touch screen) would be nicer, of course, but you pay for that.

Last time I used a 331 (332 without spec-an). It was a couple years ago.  When people find out you have it, you can rent it out.  I've rented.  When you need it, worth its weight in gold, almost literally.
Title: Re: Spectrum Analyzer/TG purchase decision
Post by: Richard Head on May 06, 2014, 06:16:50 am
The Rigol is a piece of junk compared to a proper spectrum analyzer such as HP/Rhode & Schwartz/Anritsu/Advantest etc.
Do this test on a Rigol:
Enable the TG and disconnect the bridging cable between the TG and SA input. The SA should show a flat line.
The TG leakage is so bad on the Rigol that the SA trace rises to about 30dB above the noise floor.

Does the Rigol use a YIG oscillator? No, a synthersizer. Phase noise, what's that?
It's a cheap RF instrument with all the gimicks such as USB/colour screen etc added. I would much rather have a reliable HP8593 or similar, as old as they are.

Title: Re: Spectrum Analyzer/TG purchase decision
Post by: eurofox on May 06, 2014, 08:05:01 am
... decide between a new Rigol DSA-815TG with the VB1020 bridge ...

You can alternatively use the Mini Circuits Coupler "ZFDC-20-5+". Much cheaper, works also perfectly with the VSWR option.

Cheers
hammy

Hi hammy,


Could you give us an idea of price and link where you got it in EU?

Thanks,

eurofox
Title: Re: Spectrum Analyzer/TG purchase decision
Post by: Neganur on May 07, 2014, 06:05:38 am
ZFDC-20-5+ sounds like the thing that very seldom pops up on ebay, the 1 GHz version ZFDC-20-4 is a bit more frequent.
Probably easier to just get one directly from Minicircuits?
Title: Re: Spectrum Analyzer/TG purchase decision
Post by: hammy on May 09, 2014, 08:21:57 pm
Could you give us an idea of price and link where you got it in EU?

Go to minicircuits.com -> Model No. Search -> "ZFDC-20-5+"
I purchased it there a year ago and paid, with shipping from England to Germany, 73.- €.

Cheers
Hammy
Title: Re: Spectrum Analyzer/TG purchase decision
Post by: rgreen on May 16, 2014, 02:15:22 am
Not sure what you have been using, but an HP8591E with option 010 would work well.  I think you can find the HP under $2500 although most on ebay are without TG (adds about a grand).
-Red
Title: Re: Spectrum Analyzer/TG purchase decision
Post by: kberlen on May 16, 2014, 05:50:11 am
Thanks to all who have taken the time to respond. I settled on a Tek 2712 with the TG option. Sounds like a better fit for me than the Rigol unit.
Title: Re: Spectrum Analyzer/TG purchase decision
Post by: Pinkus on May 16, 2014, 03:33:00 pm
Thanks to all who have taken the time to respond. I settled on a Tek 2712 with the TG option. Sounds like a better fit for me than the Rigol unit.
I had a 2712 without a TG and sold it to purchase the Rigol with TG and I am not disappointed about the Rigol - especially when 'improved' with 10 Hz bandwidth and some other features etc.