Relay Drive Applications
1.1 Component Switching
The most common use of the "OUT" test is to close a relay
in order to introduce an additional component to the test circuit, such as
a resistor, as shown in Figure 2 below.
Figure 3 (right) shows a block diagram of the relay output, which is
internal to the AT.
1.2 Component Adding Applications
- The most common tests where the introduction of a component is required
are to measure impedance mismatch between the transformer and the
The component, in those cases, would be a resistor for tests such as GBAL
(General Longitudinal Balance), LBAL (Longitudinal Balance), ILOS
(Insertion Loss) and RLOS (Return Loss).
- Discharging the circuit may be required where testing involves passive
components such as capacitors. These may require discharging prior to
operator removal of the part under test.