11 Sep
2025
11 Sep
'25
12:30 a.m.
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