Spectrum Analyzer - Rigol DSA815

[rf-loop]

In these images HP have 3MHz RBW and Rigol 1MHz RBW.  Of course it can calculate but it is better to compare with same RBW.
No big difference but some. Noise is related to RBW so that RBW divided by 10 drops noise floor 10dB.

[G0HZU]

I find it a bit odd that the noise floor with no input is so high 
Should be 20 db lower... still all pics I've seen shows the traces around the middle of the display.

Maybe we could have someone  test and verify that the instrument do meet the specs wrt. noise floor and sensitivity vs. RBW, especillaly with wider filters

Yes, it does look very high... Looking at the specs the noise figure with the 10dB attenuator inline is about 49dB.

So the noise floor with a 1MHz RBW should be about -65dBm. But the default detector is the peak detector and if the VBW is also up at 1MHz then this will lift the trace up by several dB.

So this could make the trace hover around -57dBm on a wide span.

If the 1Hz noise marker function was activated it should auto switch across to the 'sample' detector and if a bit of averaging is switched in then I'd expect the noise marker to show a noise floor of about -125dBm/Hz with the 10dB attenuator selected. This is based on the spec sheet so the actual result could be a bit different 

BY contrast, my HP8566B shows a noise floor of -139dBm/Hz at 145MHz with the 10dB attenuator selected and the (corrected) 1Hz noise marker function. If the RBW is set to 1MHz and the sample detector is selected then the noise averages at just under -80dBm on the display. However this noise level isn't 'corrected' (eg the nature of the log detector will affect the displayed noise level) and the true noise level will be a little bit higher. It should be about -79dBm in a 1MHz bandwidth if it was corrected.

[gmit77]

we will see a new Rigol 6GHz spectrum analyzer most probably begin of 2014.
6GHz RF Generator has been already released 

The DSA815 10 Hz RBW option was initially released to sell in the U.S. for $499, but was discontinued prior to any sales. It is currently planed for incorporation into the up coming DSA830 3 GHz Spectrum Analyzer.

Who gave you this kind of information? I'm wondering why Rigol should add another 3GHz Spectrum Analyzer? DSA830 + DSA1030 + DSA1030A for me this step makes no sense.

Rgds
Tom

[Pinkus]

I need some help with my DSA815:
I am using all my measurement stuff such as my scope and my DSA815 on a switchable power strip.
By this I avoid that they are powered all the time. When switching the power strip to 'ON', all devices should show the heartbeep on the power button, waiting to be pressed to power up the needed device.
Now to the problem:
For quite some time now the DSA815 switches on (powers up) immediately when I switch on the power strip. I hasn't done this from the beginning, so I assume I might changed a menu entry but I cannot find such an entry. I even have no idea if there is a menu item to avoid that. I already tried to set it back to factory default but no change.
Is there anything I oversaw? Any hidden menu item to select this behaviour?
Thanks for your help!!

[mrflibble]

For quite some time now the DSA815 switches on (powers up) immediately when I switch on the power strip. I hasn't done this from the beginning, so I assume I might changed a menu entry but I cannot find such an entry. I even have no idea if there is a menu item to avoid that. I already tried to set it back to factory default but no change.
Is there anything I oversaw? Any hidden menu item to select this behaviour?
Thanks for your help!!

Maybe something silly as "resume on AC power loss". If that's the case you should see a difference in behaviour between:

- have DSA815 turned on, switch off power strip, wait a bit, turn on power strip
- have DSA815 turned on, then turn off DSA815, then switch off power strip, wait a bit, turn on power strip

Unfortunately can't check that because I don't have a DSA815 (yet).

Deciding if I should buy one or not. The DSA815-TG with bandwidth hack looks pretty interesting. That said, this model has been around for a while, so maybe when Rigol introduces new models in 2014 the price will come down. Also, what are the chances of 2014 versions of the DSA815 (maybe new board revisions?) still are hackable?

[Pinkus]

Thought that too, but I could not find an option for "resume on AC power loss".
If nobody knows this behaviour nor can help, I shall send a mail to Rigol to ask about this.

[mrflibble]

Thought that too, but I could not find an option for "resume on AC power loss".
If nobody knows this behaviour nor can help, I shall send a mail to Rigol to ask about this.

Well, you'll have to look for the Chinglish equivalent. So probably something like "return after the loss of milk requirement".

[Rory]

I need some help with my DSA815:
I am using all my measurement stuff such as my scope and my DSA815 on a switchable power strip.
By this I avoid that they are powered all the time. When switching the power strip to 'ON', all devices should show the heartbeep on the power button, waiting to be pressed to power up the needed device.
Now to the problem:
For quite some time now the DSA815 switches on (powers up) immediately when I switch on the power strip. I hasn't done this from the beginning, so I assume I might changed a menu entry but I cannot find such an entry. I even have no idea if there is a menu item to avoid that. I already tried to set it back to factory default but no change.
Is there anything I oversaw? Any hidden menu item to select this behaviour?
Thanks for your help!!

Page 2-110.

http://www.rigol.com/download/Oversea/DSA/User_guide/DSA800_UserGuide_EN.pdf

[ted572]

DSA815-TG Spectrum Analyzer - 121 VAC Power Consumption:
Measurements are considered approximate due to uncertainty of measurement equipment accuracy, although should be very useful as general figure of merit.

Standby Mode (AC plugged in, OFF)
   W      1
   VA    7
   A      0.06
   PF    0.18

Operating Mode (Power ON), TG OFF/ON
   W     21/24
   VA   22/26
   A      0.18/0.21
   PF    0.96/0.91

[Pinkus]

Page 2-110.

Thank you Rory. I'll try this out, probably it is the solution to my problem.

[ted572]

Minimum Loss 50 to 75 Ohm Matching Pad for Rigol DSA815-TG

How to make one, and why you might want to. . .
See PDF attachment:

[ted572]

RF Input Limiter for Spectrum Analyzer (DSA815, or any other)

How to make one, and why you might want to. . .
See PDF attachment:
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Why would I want to bother with this?

Provides for being able to have full sensitivity on the DSA815 while still being automatically protected from a high level signal that may suddenly, or unexpectedly appear on the antenna, etc.

Nothing to screw on and off, and nothing to get screwed !

[olsenn]

RF Input Limiter for Spectrum Analyzer (DSA815, or any other)

How to make one, and why you might want to. . .
See PDF attachment:

I just have a 30db attenuater connected to the input of mine. If the attenuated signal is too small to pick up over the noise floor of the instrument, I just enable the pre-amp, or worst case scenario, just unscrew the attenuater.

[jstarr]

I just got my DSA-815-TG, calibration dated Oct 2013.  I only see 5 options.  Opt 2,4,5 are trials and counting down while Opt 3 is not active.  As far as I can determine the inactive option is the 10Hz RBW.  Were there any other options in earlier manufactures, I have seen 6 options in other posts?

john

[Sparky]

I just got my DSA-815-TG, calibration dated Oct 2013.  I only see 5 options.  Opt 2,4,5 are trials and counting down while Opt 3 is not active.  As far as I can determine the inactive option is the 10Hz RBW.  Were there any other options in earlier manufactures, I have seen 6 options in other posts?

No.  There is only 5 options.

Option 1 = TG (Tracking Generator)
Option 2 = AMK (Advanced Measurement Kit)
Option 3 = 10Hz RBW
Option 4 = EMI (EMI Filter & Quasi-Peak Detector)
Option 5 = VSWR (VSWR Measurement)

[jstarr]

Thanks, any idea why they would not give a trial of the 10hz RBW along with the other trials?

j

[ted572]

Thanks, any idea why they would not give a trial of the 10hz RBW along with the other trials?

j

Option 3, 10Hz RBW is NOT offered as a Trial because it is not available for purchase.  At one time they were considering offering it for US $499, but that idea was squelched quickly.  Then someone at Rigol China made a blunder and activated it as a Trial early in 2013 on a limited number of units.  Of course people that were familiar with the use of a Spectrum Analyzer (engineers/technicians) immediately wanted it.  Oh - So Sorry Charlie!, was the response.

Although it is embedded in the Firmware, so if you activate it with the Keygen (available here in the forum), you should be blessed with having it!  Let us know if you are unable to activate it it.  Don't wait until the next firmware update to do it, that may be too late(?).

[Rory]

Keygen options work fine with firmware version 00.01.07.

10 and 30 hz bandwidths available. Just require long sweep times and narrow span to be useful.

[Velund]

Don't wait until the next firmware update to do it, that may be too late(?).

Looks like I'll leave my DSA with current firmware (00.01.07) unless something really useful will appear in updates.

[hpux735]

I just got one of these (DSA815-TG).  I'm loving it so far.  I have noticed the instantaneous dynamic range is a bit underwhelming.  While performing tests on a home made 1013.3 MHz cavity filter I hit the noise floor before the filters ultimate rejection (should be about 100dB).  But, other than that, very happy.

[Velund]

While performing tests on a home made 1013.3 MHz cavity filter I hit the noise floor before the filters ultimate rejection (should be about 100dB). 

Hm... Did you turn preamp on during that measurement?


By the way, does anyone looked at KE5FX GPIB toolkit and, more specifically, PN, aurtomated phase-noise measurement  tool?

http://www.ke5fx.com/gpib/pn.htm

Is it technically possible to add Rigol support to that tool? Even with all limitations..... Maybe there will be really good use for 10 Hz RBW option.

[hpux735]

While performing tests on a home made 1013.3 MHz cavity filter I hit the noise floor before the filters ultimate rejection (should be about 100dB). 

Hm... Did you turn preamp on during that measurement?

I did.  But after playing with it some more, it seems like the amplitude menu/system is kinda buggy.  It's entirely possible that I don't know what I'm doing, but it seems like the reference level adjustment doesn't do anything sometimes.  I can change the value, and the ref level text in the top-left changes, but the graph doesn't change nor do the labels on the grid lines.  If I play with it enough, sometimes I can get it to do what I want.  I'll try again now that I know that.

Has anyone else noticed this?

[hpux735]

I've narrowed it down to the tracking generator, in both counts.

Buggy amplitude menu:  Only happens when you are working with a normalized TG output.  I would expect that when I normalize the TG, it should have a trace at 0 dBm (which I should be able to change in the normalize menu, and can).  Then, everything should behave as normal.  I should be able to move the reference trace (in the ampt menu) up or down.  Up, for filters, down for amps.  This doesn't work.  If I turn the normalization back off (and accept the 4dB or uncertainty) it works as expected.

Noise floor/Dynamic range: When the tracking gen is running, the minimum value I can get out of the noise floor is -94dBm.  Try it.  Turn on the preamp, your narrowest RBW (10Hz in my case).  Let it run for a bit with the power average.  Now, clear the trace, turn off the TG, and do it again.  At 1034 MHz I'm getting -140dBm.  This is pretty disappointing.  All I can really say, is that my distant rejection of my filter (which would block the image frequency) is better than 100dB.  That's O.k., I guess, but not ideal.  I'm thinking about using another signal generator to perform the measurement.

Ideas?

[Pinkus]

FYI: there is a new firmware for the DSA815 available

Version?00.01.08.00.03   Date?2013-12-02
1.      Solve the problem some spelling mistakes
2.      Temporary solution to the problem LXI communication is unstable.
3.      Increased multi-language support, including Portuguese,German,Polish,Korean and Japanese.
4.      Solve the problem marker table and PF don’t display correctly.

[Vtech]

I've attached the new firmware 00.01.08 (full name 00.01.08.00.03) dated 2013-12-02
Since this forum limits single file size to 1MB I had to split it using 7zip and change file extension.

Remove .zip from file name - it should be DSA800(DSP)update_00.01.08.00.03 zip.001 and DSA800(DSP)update_00.01.08.00.03 zip.002

I've successfully upgraded my DSA using Storage->{select "Mobile disk"}->{select file DSA800_UpdateFile.sys}->Sys Update.
All licenses stayed intact (including those added using keygen) and are functioning correctly. The biggest change is additional languages added.