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Unsure if this is posted somewhere already on the forum but a quick search did not reveal any hits.
I just saw from a dealer an email introducing the
DSA705 (500MHz) and DSA710 (1GHz) spectrum analyzers starting from €650.-ex VAT
Unfortunately a lower Frequency Range of 100 kHz otherwise I would love to buy one for audio.
Strange thing is that the email (picture 2) talks about the DSA711 and DSA712 typenumbers but the link refers to the DSA705 and DSA710 so not sure what that is all about but the pictures clearly show a DSA710 typenumber so I assume it will be the DSA705 and DSA710.
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Hi,
DANL -155dBm with 100Hz RBW
20 dBm better than DSA815.
Best regards
egonotto
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Hi,
Perhaps due to the limited bandwidth?
DANL -155dBm with 100Hz RBW
20 dBm better than DSA815.
Best regards
egonotto -
Interesting, 0-500MHz and 500-900MHz are the ranges in which VCO 1 and 2 (of 3 total) in my DSA815 are active, corresponding closely to the 705 and 710 models (there are LEDs inside the RF shield showing when each VCO is active, fun to look at). I wonder if they're planning to populate 1 / 2 / 3 of the VCOs depending on model to prevent, err, software-only bandwidth upgrades
?
I'm happy to see that they've fixed their noise floor issues, but since 10ms is the same minimum "sweep time" as the 815 it looks like they didn't get around to addressing the other big outstanding issue I have with these models. I put "sweep time" in scare quotes because if you probe the VCO you can see that 10ms is indeed the amount of time taken by the voltage ramp... but then there's a good 200ms of waiting in between sweeps so that the effective sweep rate is the pitiful 4 or 5 updates per second that you see on the screen
.
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Who is the 500mhz version appealing to?
ISM band 433.05 MHz - 434.79 MHz -
Hi,
Perhaps due to the limited bandwidth?
DANL -155dBm with 100Hz RBW
20 dBm better than DSA815.
Best regards
egonotto
I do not know how this is in this particular case in sales information but overall it need be careful when read.
It need know how some value is defined.
I do not know why manufactures very easy forget from salesmens advertisements this small Hz or example in some other cases they many times tell jitter rms when users still need live with jitter p-p and so on.
If example (Displayed) Average Noise Level ((D)ANL) is told as -150dBm/Hz it is clear.
But then reader need know that (if some conditional other things are true) if RBW is 10Hz, then really Displayed (visible) average noise level is 10dB higher. If RBW is 100Hz it is 20dB higher and if RBW is 1kHz then 30dB and so on.
Look here measured "D"ANL from DS800 data sheet. Nearly -160dBm/Hz
But of course it is not really Displayed. It is imagined DANL if RBW is 1Hz.
Real DANL what user see with his eyes on the screen is 20dB higher in this case. This is real DISPLAYED ANL in practice with this analyzator due to fact that RBW 100Hz is most narrow RBW what user can use.
If user select 1MHz RBW DANL is 60dB higher.
Older times many example HP specifications tell real DANL what user can see and not normalized to 1Hz Exept if there is also available 1Hz RBW.
If manufacturer have not defined it and value is on the advertisement it is mostly normalised value for 1Hz (because it looks more attractive)
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Who is the 500mhz version appealing to?
ISM band 433.05 MHz - 434.79 MHz
My opinion is that if do any kind of serious work there need look least 3rd harmonic.
So, for check example ISM band tx minimum is 1.5GHz spectrum. -
DANL should always be specified at 1 Hz BW, there is just no other right way of doing it. From there anyone can calculate the noise floor from the used RBW, no guessing. From example I mostly use 100kHz or higher RBW, since I work with wideband signals and it is easier to just start with 1 Hz noise figures and go from there.
BR -
DANL should always be specified at 1 Hz BW, there is just no other right way of doing it. From there anyone can calculate the noise floor from the used RBW, no guessing. From example I mostly use 100kHz or higher RBW, since I work with wideband signals and it is easier to just start with 1 Hz noise figures and go from there.
BR
Yes. This is your opinion and also it is my opinion. But it is opinion and nothing more.
Of course it should and when it is specified as normalized to 1Hz it need also tell. If not, it need also tell.
There is no any rule (who can set this rule?) that it NEED specify as normalized to 1Hz RBW.
Example Hewlett-Packard (old):QuoteSpectrum analyzers usually characterize this by specifying the displayed average noise level (DANL) in dBm, with the smallest RBW setting.
This is why old work horse HP8568B specs tell DANL -135dBm and it is quite good.
It is specified in data sheet with most narrow RBW what this model have and it is 10Hz. And this is true displayed average noise level with this equipment.
We can tell that (8568B) it is -145dBm/Hz (or -145dBm, normalized to 1Hz RBW) but we can not tell DANL is -145dBm, because it can not display it. D means Displayed! But if we tell -145dBm/Hz now it is clear and and right and when we know 10Hz is narrowest we simply know that oh but true displayed average noise level is -135dBm because narrowest is 10Hz.
(and there is not preamplifier "effect")
We who know these things as our pockets can not fool with this. But, I know lot of peoples who are confused with this and they are easy "fooled" with this.
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Hello,
now it is clear. In the datasheet from DSA700 series one see the -155 dBm is normalized to 1 Hz and should be -155 dBm/Hz
Best regards
egonotto
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Starting price of 650 Euros must be for the 500MHz version of the Spectrum Analyzer. They've made them to replace the 1000 Series but the good news is that they are built on a similiar platform to the DSA800 series which means it' be a better & more reliable spectrum analyzer compared to the DSA1000 series predecessor.
They also have Near Field Probes now too for the spectrum analyzers as an option.
I tried attaching the datasheet but unfortunately it said the file was too big
We are authorized distributors for Rigol in the UK and Ireland.
If anyone would like a quote please feel free to contact myself directly.
We are offering special for EEVblog members.. but any Rigol Spectrum Analyzer and get discounted pricing on any of the additional options for the spectrum analyzers. When making a request mention the EEVblog to get the above sale. Sale Ends July 31 2016.
Have a great day everyone!!
Joy Torres
Instruments 4 Engineers
Tel +44 (0) 161 871 7450
info@instruments4engineers.com
Our website is www.instruments4engineers.com it's being re-designed at the moment but we are expecting to launch the first stage of the website in the next few weeks.
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Hi! Always good to see distributors on the forum! Any chance you could give us an idea of whether the update rate on the 700 series falls into the same bin as the DSA1000 / DSA815 (4-5 sweeps per second even when SWT=10ms)
https://youtu.be/KKJqdKSkAyc?t=390
or whether it behaves like the DSA832/875 and isn't limited to 4 updates a second:
https://youtu.be/0wVlH1lPZdE?t=3478 -
I don't know off the top of my head but will find out.
Joy -
Thanks for looking into it.
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Hello jjoonathan,
I've checked with Rigol just to be certain and they've replied
"speed is the same as DSA-815, Sweep time, Trigger rate all the same."
One thing I did want to note is that the DSA700 series doesn't have a tracking generator. If you wanted a tracking gen then you'd need to go with the DSA800 series
Thanks for asking the question. Hope you have a nice upcoming weekend!
Joy Torres
Instruments 4 Engineers
Tel +44 (0) 161 871 7450
info@instruments4engineers.com
www.instruments4engineers.com
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Thanks, you too. On one hand I can't help but be a bit disappointed... but on the other at least my 815 will hold its value a bit longer
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Seriously, no tracking generator? Pshh useless...
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Most of the SA at work don't have a TG and I find them very useful!
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But if you need to do a VSWR measurement, and/or work with antennas, for HAM stuff, kind of tough.
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Oh, but the phase noise!
Take a look here:
http://www.rigol-uk.co.uk/Rigol-DSA710-1GHz-Spectrum-Analyser-p/dsa710.htm
The image titled "80dBcHz @ 10kHz offset Phase Noise".
I fed a 1GHz signal into my 8568A (see attached picture, sorry about camera shake), used the same settings and got -79.6dB in a 1KHz bandwidth, so -109.6dBc/Hz. A good 20dB better.
Compare and contrast the two pictures. The Rigol does win on sweep time, managing 2.5 seconds vs the 8568A's 7.5 seconds.
The 1GHz was from an Si570.
Much as I'd like to replace the 8568A with something smaller, I think it would be giving up too much in terms of performance.
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But if you need to do a VSWR measurement, and/or work with antennas, for HAM stuff, kind of tough.
You pull out an RF generator and configure it for a stepped sweep. FM modulate some noise to allow for bigger steps and use trigger out/trigger in to connect the instruments and synchronise the generator output with the SA sweeps. OK it will be much slower than using the tracking generator but it will work. -
At the risk of sounding a bit pedantic, you aren't measuring the phase noise correctly with your 8568A. You should really measure it with the 1Hz noise marker function in order to measure the noise level properly as this uses the correct detection method and includes the relevant corrections to display the noise level. Then you can work out your dBc/Hz from the carrier power.
It looks like you have one of the LCD replacement screens. How does it compare to the old CRT for typical use?
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At the risk of sounding a bit pedantic, you aren't measuring the phase noise correctly with your 8568A. You should really measure it with the 1Hz noise marker function in order to measure the noise level properly as this uses the correct detection method and includes the relevant corrections to display the noise level. Then you can work out your dBc/Hz from the carrier power.
It looks like you have one of the LCD replacement screens. How does it compare to the old CRT for typical use?
OK, here is the screenshot using a noise marker. Carrier is -1.9dBm, noise marker claims -109.7dBm, so it's looking like -107.8 dBc/Hz. The 8568A is supposed to be 100dBc at 3kHz and 107dBc at 30kHz, so it seems reasonable to me.
Yes, the LCD is one of the Newscope LCDs, actually a beta model; I just haven't upgraded to the production model yet. I didn't deliberately put up the NewScope version on the screen, I just happened to hit the right magic string with the marker frequency. I think the picture says it all as to the quality and usefulness of the NewScope LCD. It's much better than the dim CRT it replaced. This particular LCD module isn't very bright, but it was my choice to take a dimmer LCD module when I got it. Certainly, I wouldn't go back to the CRT. In theory the CRT had more resolution, but I'm not reading values off the trace anyway, that's what markers are for! In addition, the NewScope is far better at zero-span mode with very fast sweeps - it is rock solid at 1us, whereas with the CRT, I got a dim trace that started offset from the left edge of the screen.
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FWIW...
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FWIW...
Thanks! I was going to use pn.exe with my 1GHz signal, but the 8568A wasn't hooked up to GPIB, and I found the Shift-M command... I need one of those pull-out command references - I never remember all the different shifted commands.