PSM1700 PsimetriQ user manual
A-3
75 / 600 output adapter
The generator output from the PsimetriQ has a series
impedance of 50. The output adapter fits directly onto
the front of the instrument and provides 2 outputs:
75 via a BNC connector
600 via 4mm sockets.
There are two versions of the adapter that have different
spacing between the 4mm sockets:
½” (12.5mm) as commonly used for communications.
¾” (19mm) as standard on instruments.
In both cases, the red connector carries the output signal,
the green or black connector is 0V (connected to earth via
the PsimetriQ chassis).
The impedance conversion is resistive and does not limit
the frequencies available from the generator (dc coupled).
When driving into the characteristic impedance (75 or
600 as appropriate) the voltage delivered to the load will
be half that delivered into open circuit.
Matching the source to the load impedance minimises
reflections at higher frequencies and improves transient
response, especially when driving long lengths of cable or
transformers.
Part numbers