Marco:

I also noticed DCF39 was off air at about 0100utc last night. It was
back on again later.

I was starting to think I had an intermittent in the system at one point.

Larry, have a small signal generator tuneable on 137 kHz at hand.
When in doubt, radiate a few microwatts .... in my shack this technique
is used often and works well.

Thank you for your kind help.  I have a tiny TTL level signal generator here
that I think I will put out at my HF transmitter site as soon as have time
to get it working properly hi.   Your thought is much appreciated.  We did
the same thing many years ago when I was looking after OSCAR VI, I kept a
29.39 megaHz one transistor oscillator in a neighbours garage for some years
so I could check that the receiver was really working hi

Larry
VA3LK

.