Hi Roelof,
In the moment it's just in my mind, not on the paper. I thought it is no
good idea to publish anything as long as the problems are not solved.
Of course all the problems are not only coming from the circuit design
but also depend on the local situation. The AFN signal is a good
example. I still don't know why it took so long until i discovered this
strong signal. Another issue is the grounding situation, cable length
and also the frequency response of the input impedance of a receiver.
All this may let a circuit design appear as a nearly perfect solution in
the one location but appers as complete rubbish in the other location...
Just found another bug: The IM coming a few seconds after adding the 50
Ohm termination load are coming from a 0.1 A poly switch fuse which is
in the supply path of the RX, which feeds the probe. I should have
switched 1 uF in series to the 50 Ohm, not to apply DC, of course. First
i remembered the fuse but thought that this can't be the problem because
there are still signals shown on the MF RX. The fuse does not lower the
voltage to 0V but to 2V which seems to be enough to produce some signals
for the MF RX, which has its own supply voltage.
I'm going to make a drawing...
73, Stefan
Am 09.10.2012 15:50, schrieb Roelof Bakker:
Hello Stefan,
Where can I find the circuit diagram of your probe and also of the
"Fernspeiseweiche"?
73,
Roelof, pa0rdt
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