13
Switchers
You may elect to use a separate switching device for source selection. Typically a
switcher will have serial control. This simplifies setup of your display. Many
switchers will switch both audio and video. This needs to be taken into
consideration when you are designing the audio portion of your system.
Audio
control
In a simple AV system, there are many options for audio output. Many systems use
the audio output from the display in conjunction with an external amplifier and
speakers. This simplifies audio control. In this design be sure the display has the
ability to control any outputs to the amplifier.
There are other hardware devices in a typical A/V system where the audio levels
can be controlled. A typical example of this is through an amplifier, switcher or
mixer. The decision on which device controls the audio levels, is important to the
design of the control system. Again be sure the device you choose to adjust audio
levels has the appropriate control capabilities.
Screen
Control
Screen manufacturers have many options available for control. When designing
screen control into an AV system there are many methods to choose from. Many
manufacturers provide the option of either serial, IR, or contact closure control for
the screen. If you elect to use contact closure check the specifications from the
manufacture. You may require an external serial to relay converter such as the FSR
Intelli‐tools ITR4S to control your screen. Check the voltage requirements from the
screen manufacture.
Distance
Limitations
When designing a system it is important that the wiring for communications does
not exceed the published distance limitations. The distance limitations for the FLEX
hardware are listed above in the hardware section of this manual.
IR
Considerations
One of the challenges when using IR in AV system is syncing the different devices to
ensure when a power button is pressed the system actually comes on. You may want
to add a separate on/off button to any IR device screen to ensure they can be
powered to the desired state.
Serial
Considerations
Manufacturer’s serial command sets differ greatly. It is important to be sure that the
device drivers are readily available. Serial commands also vary greatly in
complexity. Here are two examples of the “Power On” command”
Power On C00
Power On 02H 00H 00H 00H 00H 02H
A complex serial command set increases the potential for communication issues.
