EMRFD Message Archive 14908

Message Date From Subject
14908 2018-07-03 09:24:14 nothdurftm Siglent vs Rigol

Anyone have a comment on the Siglent SSA3021X vs Rigol DSA815-TG.  The Siglent is somewhat more expensive but seems to have better specs.

Thanks

Mike

K5ESS

14909 2018-07-03 09:36:28 Clint Re: Siglent vs Rigol

Both units are great boxes.  I had my Rigol for about 4 years –huge improvement in most areas, over my previous Tek 496.  I have had my Siglent since April.   I needed the Siglent in order to measure crystal notch filters with notches exceeding 80 dbm.  There was too much TG leakage on the Rigol, so I could not measure notches below -80 dbm, even though the actual notch was around -90 dbm.  I recently noticed that the Rigol, being smaller in size, is much easier to carry around to different sites.

 

Here is some of my evaluation results:

 

My testing results on the Siglent were almost identical to the results in this YouTube video:

 

https://www.youtube.com/watch?v=gkLciTsjGZg

 

The Siglent now includes the tracking generator option in the $1200 price and it supports RBWs of 1 Hz and 3 Hz.  The newer Rigol units supports a RBW of 30 Hz.  I have an older Rigol unit and the lowest RBW is 100 Hz.  I found that my displayed average noise level was about 10 db lower than what Dave measured in the video.


I did a number of checkpoints and captured the images from each unit.  Here are some items that caught my attention:

 

The detents on the main tuning control of the Rigol are more distinct that the ones on the Siglent.

 

The Siglent does not give you a message if you try to save a screen capture with an existing file name.  Thus you will over-write any existing file.

 

With the Rigol, I could always enter a starting frequency and a stopping frequency and the 815 would adjust the other settings accordingly.  With the Siglent, I have to adjust the other configuration settings before I set the start and stop frequency.  Otherwise, in some cases, the start and/or stop frequency would not take.

 

The markers on the Rigol unit appear to be more distinct for actual level/frequency positions than the markers on the Siglent unit

 

In the Tracking Generator mode, normalization results in a very flat line (at the 0 db level) on the Rigol unit.  There are sometimes some little blips on the Siglent unit.

 

IMHO, there are two major downsides with the Rigol, when compared with the Siglent.  The Siglent has significantly lower phase noise and it also has significantly lower tracking generator leakage between the output of the tracking generator and the input of the spectrum analyzer.  To the maximum extent possible, I tried to use the same configuration settings for a given checkpoint.  

 

The attached spreadsheet shows the checkpoints and the configuration settings:

 

1.       Baseband noise

01     PA Off        Siglent has about 5 db less noise with a 10 Khz RBW.  Notice the flat noise baseband on the Siglent

02     PA On         Siglent has 1 to 10 db less noise with a 10 Khz RBW.  Notice the flat noise baseband on the Siglent.

03     PA Off        The sweep on the Rigol was extremely slow and would not complete.  The screen snapshot shows the partially completed sweep.

04     PA On         The sweep on the Rigol was extremely slow and would not complete.  The screen snapshot shows the partially completed sweep.

05     PA On         The sweeps are about the same for the 100 Hz RBW.  That is the lowest available RBW on the Rigol.  On the Siglent, sweeps are also shown for 30 Hz and 3 Hz.  Notice the very low baseband noise on the Siglent at the 3 Hz RBW setting.

 

2.       Signal Display – signal from my low noise Wenzel oscillator

06  PA Off        significantly lower noise on the Siglent

07  PA On         significantly lower noise on the Siglent

 

3.       Phase Noise

08 PA Off         Siglent has 13 db lower phase noise at a 10 Khz spacing.

 

4.       Tracking Generator

09 PA Off         TG normalized, then cable removed.  Siglent has about 32 db less noise leakage

10 PA On          TG normalized, then cable removed.  Siglent has about 27 db less noise leakage

11 PA On          SA setup for normal measurement, then TG turned on.  Rigol has a weird looking noise baseline that could be flattened by adding more ATT attenuation.

 

5.       Chinese Noise Generator ($29 unit – best of the Chinese units)

12 PA Off         10 Khz – 500 Mhz        dbm/hz about the same for both units – within 1 db of each other

13 PA Off         10 Khz – 30 Mhz           dbm/hr about the same for both units – within 1.5 db of each other

 

6.       Filter Sweeps

14 PA Off         316-8160 Khz band pass filter – both units look about the same

15 PA Off         40M band pass filter – both units look about the same

16 PA Off         316-17300 Khz band pass filter – both units look about the same

17 PA On          5645 Khz Drake SSB 2.3 Kh filter – Siglent skirts are about 5 db deeper close to the noise baseline

18 PA On          7600 Khz Wandel Band Limit filter – Siglent has a 10 db deeper notch – had to drop Siglent ATT value to 40 in order to get rid of ADC Overload error

19 PA On          14312 Khz crystal band limit filter – Hammond box – Siglent unit has about 10 db deeper notch

20 PA On          14312 Khz crystal band limit filter – breadboard – Siglent unit has about 10 db deeper notch

 

7.       Off the Air Monitoring

21 PA On          AM Broadcast band                              spectrum about the same for both units – appears to be some noise humps on the Rigol display

22 PA On          FM Broadcast band                               spectrum about the same for both units

23 PA On          NOAA VHF Weather Stations              spectrum about the same for both units – noise baseline on Rigol is about 10 db lower than the Siglent

 

73

Clint

W7KEC

 

 

 

14910 2018-07-03 10:59:41 Myron Cherry Re: Siglent vs Rigol
If you are an ARRL member, you can look at product reviews on both of them. The Rigol was reviewed in QST Feb 2013 and the Siglent was reviewed in QST Nov 2016.

I can’t comment on the Siglent, but I do have the Rigol DSA815-TG and I’m a very happy camper.

Myron….K4YA


14911 2018-07-03 14:46:02 Russ Hines Re: Siglent vs Rigol
Hello Mike and list:

I own a Rigol DSA815-TG, have had it about 3 years, did the firmware upgrade (free) to get it to 10Hz RBW, and it's been mostly adequate for my needs.  A nice piece of RF test equipment. 

But as soon as I can, I will be acquiring the Siglent SSA3021X, mostly because of the nearly 20dB better phase noise performance.  Add the 2.1 GHz freq span (the Rigol is 1.5GHz), I think it's a better deal.

What's really interesting is the new Siglent SVA1015X.  Check that one out.  Enticing. ;-)

73,
Russ Hines JMS & Associates, Inc. SBE CSRE WB8ZCC -- Reply to: russ@wb8zcc.com
14912 2018-07-03 14:46:06 Mike Nothdurft Re: Siglent vs Rigol

Clint,

Thanks for your detailed reply.  Very useful information for making my decision on which to buy. I’m thinking Siglent.

Myron,

Also thanks for your reply.

Mike

K5ESS