Siglent power supply noise

[pherdie]

At Christmas time I put up outdoor lighting that for convenience sake, is switched by the use of power line carrier (RF) modules.

This year, after completing installation of my lights, I had one power control module that failed to respond to control signals. Some quick trouble shooting seemed to indicate the module was fine but unable to receive signals, possibly due to noise on the power circuit. I have approximately fifteen pieces of test equipment on the same circuit, so I started a process of unplugging test equipment to see if the problem resolved. I found that two Siglent devices I had acquired during the past year were both independently generating enough power line noise (when turned 'off') to render my control module inoperative, a Siglent SDG2042X function generator and a Siglent SSA3021X spectrum analyzer.

I have made no further tests at this time to investigate the issue due to other personal obligations but thought that now sharing this information may be of use to others.

[tautech]

The SDG2042X shouldn't be putting anything on the mains supply when Off as it's hard switched.
The SSA3021X on the other hand is not, it's SMPS is in idle mode when powered and Off.

Yes, please dig deeper into this when you have some time.

[JDubU]

Have you checked your wall outlet wiring to verify that it is properly grounded and that the hot and neutral are not swapped?