PSU - LED driver interference cured
Posted: Fri Dec 15, 2023 12:03 am
We had a lightning hit. Ouch!
Among various electronic casualties, was the 12v PSU - LED driver for the XYL's hot tub. Urgent replacement proceeded with a well-reviewed (ASIN B07Y61R8SR) Amazon's choice, Ce,ip67,rohs unit. The hot tub started up and the LEDs looked pretty. The XYL marinated happily, while I went to play radio. No good! QRN 30db over was present on 160, 80 and 60, getting a little better on 40m. Closer inspection of the many favorable reviews showed no mention of radio interference in the many reviewers recommending the product.
The new device was replaced with another maker's product (ASIN B0BM5NK249) which was one of the very few that claimed to be radio-quiet, and it proved to be a great improvement on the first, but still a little noisy.
Next, multiple ferrite cores were applied and a filter on the PSU input (ASIN B08J7FJ1XZ) and on the output (ASIN B00MU2HM2U), all with little improvement until the hot tub was fitted with an optional ground.
While sufficient insulation might make the spa safe to use, a ground is needed with the filters to provide a path out for filtered RF.
Now both XYL and OM are happy!
Among various electronic casualties, was the 12v PSU - LED driver for the XYL's hot tub. Urgent replacement proceeded with a well-reviewed (ASIN B07Y61R8SR) Amazon's choice, Ce,ip67,rohs unit. The hot tub started up and the LEDs looked pretty. The XYL marinated happily, while I went to play radio. No good! QRN 30db over was present on 160, 80 and 60, getting a little better on 40m. Closer inspection of the many favorable reviews showed no mention of radio interference in the many reviewers recommending the product.
The new device was replaced with another maker's product (ASIN B0BM5NK249) which was one of the very few that claimed to be radio-quiet, and it proved to be a great improvement on the first, but still a little noisy.
Next, multiple ferrite cores were applied and a filter on the PSU input (ASIN B08J7FJ1XZ) and on the output (ASIN B00MU2HM2U), all with little improvement until the hot tub was fitted with an optional ground.
While sufficient insulation might make the spa safe to use, a ground is needed with the filters to provide a path out for filtered RF.
Now both XYL and OM are happy!