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Products => Test Equipment => Topic started by: cyberfuzzy on March 26, 2018, 10:36:58 pm

Title: Rigol DSA815 - problem with tracking generator?
Post by: cyberfuzzy on March 26, 2018, 10:36:58 pm

Hi. I'm not sure if there is a problem with the tracking generator of my Rigol DSA815. When I watch the signal with the scope it looks like the graph is not sinusoidal for <1 MHz.

I recorded a sweep from 500 kHz to 1.5 MHz, sweep time is 10 seconds:
https://www.youtube.com/watch?v=LPiW3uxheMQ (https://www.youtube.com/watch?v=LPiW3uxheMQ)

On the spectrum analyzer the graph shows -18.1 dBm at 500 kHz and -19.2 dBm at 1.5 MHz. I don't think that the cable (RG-58) is that bad:
(https://www.eevblog.com/forum/testgear/rigol-dsa815-problem-with-tracking-generator/?action=dlattach;attach=407048;image)

The setup is a cable from the tracking generator to the scope and back to the input of the spectrum analyzer:
(https://www.eevblog.com/forum/testgear/rigol-dsa815-problem-with-tracking-generator/?action=dlattach;attach=407050;image)

Can anybody reproduce that issue? Is there a problem with my tracking generator or does every DSA815 act like this?

Title: Re: Rigol DSA815 - problem with tracking generator?
Post by: cyberfuzzy on March 28, 2018, 10:36:49 am

According to this thread it seems to be normal for those cheap spectrum analyzers:
https://www.eevblog.com/forum/testgear/rigol-dsa-815-tracking-generator-distortion/ (https://www.eevblog.com/forum/testgear/rigol-dsa-815-tracking-generator-distortion/)

On my DSA815 the signal does not look sinusoidal for frequencies below 1 MHz. I took 3 screenshots with the scope for 10 kHz, 100 kHz and 1 MHz at zero span.