RIGOL DSA815-TG @ 10 MHz issue/bug

[pa3bca]

Well the frequency shift with the TG (as a function of the RBW/sweeptime) seems to have been fixed with the .15 firmware.
However I still have the amplitude jump just below 500 KHz (also see my previous postings)
With all settings default and the RBW set at 10 KHz (span from 300-700 KHz) the jump is very present:


RBW reduced to 1 KHz.

No frequency shift (fixed, good!) but the amp jump at 10 KHz RBWE.. not so good.
Did they only look at & fix the 10 MHz issue? Funny thing is my 815 never had the 10 MHz amp jump issue.

[N8AUM]

Power sweep seems to work ok with mine. Havnt had time to play with it. Just got more boat anchors in that am currently playing with, 8566B, 8350B with 83595 plugin, 54502A and a 5342A 

[Howardlong]

Power sweep seems to work ok with mine. Havnt had time to play with it. Just got more boat anchors in that am currently playing with, 8566B, 8350B with 83595 plugin, 54502A and a 5342A 

I did a quick test, but it looked like the sweep didn't cover the range and/or base supplied in the UI: the maximum I could get was from about -16 to -2dBm, and only over about 1/2 of the span with it flatflining at the start and end, but that is compared to no change at all as it once was.

[N8AUM]

Here's a screen shot of power sweep enabled with the latest firmware.

[N8AUM]

Thanks for the PM Ted.

Quick observation with my 815. With the RBW set at 100 Hz I can go as low as 524 Hz span and still have the full 20db swing from low end to high end. That shows up as 9 steps on the sweep.
 

[Howardlong]

I did a quick test, but it looked like the sweep didn't cover the range and/or base supplied in the UI: the maximum I could get was from about -16 to -2dBm, and only over about 1/2 of the span with it flatflining at the start and end, but that is compared to no change at all as it once was.

Howard:  The original "DSA815-TG 'Power Sweep' Mode" instructions (.pdf file) that I put together and posted worked fine for me and others with the original DSA815 hardware, but doesn't work the same now with the new 1.15 FW.  The big thing is that Power Sweep doesn't seem to work properly with 100 Hz SPAN, so I changed it to 300 Hz.  It will also work with larger Spans but results are shifted horizontally.  For now I recommend using 300 Hz.  Please play with it and let me know what you think.  Anyway hopefully it will now work for you, or at least get you better in the ball park.

Please use the revised procedure attacked below.  Thank you, Ted

I used your originally ;-)

On the SA I have here under 1.15, I need a span of at least 1.315kHz to be able to see all 20 x 1dB steps of resolution in use. Beyond that, at low spans, the steps become non-equidistant, but above a few kHz it's probably not a problem... unless you're trying to measure an amp with a narrow band filter!

[Howardlong]

Thanks for the PM Ted.

Quick observation with my 815. With the RBW set at 100 Hz I can go as low as 524 Hz span and still have the full 20db swing from low end to high end. That shows up as 9 steps on the sweep.

Same here, but there are only 10 steps of 1 or 2 dB rather than 20 steps of 1dB. 1.315kHz span gets you the full 20 x 1 dB steps.

[N8AUM]

 My toy had 34hrs left on its trails when I did the hardware mod. I left it on to run out the clock which of course disables the trails, and it did. Power cycled it and trails came back.   

[ted572]

Configuring the DSA815-TG for the Power Sweep mode

The changes Rigol made in DSA815 Firmware 00.01.15.01.00 required some changes to the Power Sweep mode information that I previously posted.  Please feel free to let me know if you have any questions or issues with this.  Thank you

[xrunner]

Another bug?

https://www.eevblog.com/forum/testgear/rigol-dsa815-tg-video-ave-bug/new/#top