On Sat, 6 Sep 2025, Rob Jarratt wrote:
I thought that replacing two big output capacitors on the +5V output had fixed the issue but it hasn't. The problem seems to be intermittent. I tested it a couple of days ago with a simple resistive load on the +5V and +12V outputs. The first two times I switched it on it operated normally. The third time I got no output at all. It seems to start working again after I leave it switched off for a few minutes. Over the last couple of days I have tested it multiple times very briefly with the resistive load and it has worked every time.
Did you test/replace the startup voltage capacitor on the primary side? It is usually a small one (e.g. 10µF/50V) around the switching controller, and often located near a heat sink and thus prone to fail.
BTW check all capacitors near heat sinks or power components. Christian
