REAR PANEL CONNECTIONS AND CONTROLS continued
12V Out Jack
The Trigger Out jack lets you loop or “daisy-chain” the incoming trigger voltage to an additional
Model 5250 or other component.
Note:
The Model 5250 trigger circuit draws a negligible 15 mA from the controller. The total load
on your controller’s trigger output(s) is the sum of the trigger current drawn by each of the com-
ponents you’ve looped together. Controllers can typically supply 150 mA at their trigger outputs.
Audio Trigger Sens (Sensitivity) Knob
The Auto Turn On Audio Sensitivity knob adjusts the incoming audio level or the “threshold”
required to turn on the Model 5250. Its 12 o’clock position will be suitable in most cases. To
increase sensitivity for response to lower level audio signals, turn the knob counter-clockwise
.Turn the knob clockwise toward - to decrease its sensitivity. This will prevent spurious
noise and switching transients in your system from false-triggering the Model 5250.
Note:
Plugging in the 5250’s AC cord for the first time will usually create an internal power
surge that “false triggers” its Audio auto turn on, even if there’s no audio signal at its input
jacks, and it will remain on for 10-15 minutes after you switch it off. This is normal.
Ground Switch
Ground is the normal position for this switch. If you hear background
hum in the speakers connected to the Model 5250, try setting the
Ground Lift Switch to its Lift position. The Ground Switch disconnects
or “lifts” the audio circuit ground from the chassis ground. This often
helps to eliminate audible hum that results from ground loops. Ground
loops are multiple ground paths such as the metal-to-metal contact
with the panels or chassis of other components combined with the
ground connections of the audio cables or even the ground wires of the various AC cords.
AC Power Connections and AC Grounding
If possible, plug your Model 5250 into the same AC outlet that your accompanying audio com-
ponents (especially the system controller) are plugged into. The ground potential between dif-
ferent AC outlets may be higher or lower, resulting in audible hum.
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