TD250 V8 Manual
6
Rev 2, 31-09-2020
6
Front Panel
The input and output connectors are 9-pin DSUB receptacles. The recommended mating connectors
are 9-pin DSUB male cable plugs. The connector pins on the amplifier are listed below.
Figure 2. Front view of amplifier connector numbering
Connector Pin
Input Connector
Output Connector
1 to 6
Inputs 1 to 6
Outputs 1 to 6
7
Signal Ground
Signal Ground
8
Status
Signal Ground
9
Disable
Signal Ground
Connector shield
Chassis Earth
Chassis Earth
Table 1. Front panel D-sub connector pin-out
Input Signals
The standard input voltage is +/-10V and the absolute maximum input voltage is +/-20V. Use the
signal ground not chassis earth. The input impedance is 1 MOhm when the amplifier is powered on
and approximately 1.5 kOhm when the amplifier is off. For the inverting configuration (TD250-INV),
only inputs 1, 3 and 5 are active.
Disable Input
Applying a positive voltage of between 3V and 5V to the disable pin on the front panel connector will
turn off the amplifier. The input impedance is approximately 2 kOhm. The absolute maximum input
voltage is +/-10V.
Status Output
A +5V output (relative to signal ground) on the status pin indicates that the high-voltage power
supplies are both active and not effected by any overload or disable conditions. The output
impedance is 100 kOhm. The output voltage can be reduced to 3V by shunting the output to signal
ground with any 3V Zener diode.
Output Signals
The load should be connected between each output and signal ground. Do not operate the amplifier
with exposed conductors.
Status Indicator
Green indicates that the amplifier is on and the high-voltage power supply is active. Red indicates
that the amplifier is on but the high-voltage power supplies are less than 240V due to a fault
condition. A mixture of red and green indicates that the amplifier is on the verge of overload.
1
2
3
4
5
6
8
7
9
