For each of the 4 or 8 channels there are two BNC connectors on the rear panel. One of these connectors is to be used as a video input while the other connector may be used as a looping output. It does not matter which connector is used as the input and which is used as the looping output. Each pair of BNCs provide an automatic termination function that applies a 75 ohm load to the incoming video signal when the cable is connected to either jack. When �loop-through� operation is desired, the second cable connection automatically unterminates the input providing the required high impedance for �loop-through� operation. The jacks act as automatic switches. The looping video outputs are provided to supply video to other video equipment. When looping, the last piece of equipment on the video line should be terminated
Configuration options are provided through on-screen menus. These menus are accessed by using the DWELL key. With video present on the monitor, a momentary press and release of the DWELL key will gain easy access to the Dwell Time Menu (see Screen 1).
4.4
Monitor Output
The monitor outputs are designed for a 75 ohm load. Therefore if you loop the monitor output cable through multiple monitors or their accessories, be sure their terminations are set to Hi-Z. Only the last unit on the line should have its termination set to 75 ohm. LTC 5104 Series: A single monitor output permits switched camera video through this connection. LTC 5108 Series: These switchers may be used with one or two monitors depending on system requirements. See Operating Mode section and Typical Installation illustration.
Screen 1 The remaining configuration menus (8 for LTC 5104 Series and 9 for the LTC 5108 Series) are also accessed with the DWELL key. With video present on the monitor, press and hold the DWELL key for 1 second; the monitor will display Screen 2.
4.5
Alarm Inputs and Output (Accessory Output)
A cable with a connector is supplied to connect alarm closures or other accessories to the switcher. The alarm inputs can be triggered by either a contact closure selectable (normally open or close) (e.g., switch or relay) to ground or by a logic ground (e.g., motion detector output). The alarm output creates a short between the two output pins when an alarm occurs and open-circuits the pins when no alarms are active (triggered). The alarm output has a maximum carrying current of 1 A and a maximum switching voltage of 40 V AC/DC. The alarm output can be used to signal a VCR, lamp, or relay. CAUTION: Do not apply external voltages to the alarm inputs. Use only isolated closures. Precautions should be taken particularly on long runs, to prevent pickup of spurious signals from associated wiring which may give false inputs or damage the switcher.
Screen 2 To advance through these 7 or 8 menus, press the RUN/next key. When the last menu is displayed, the RUN/next key will automatically exit the configuration mode. The configuration mode will also exit automatically if there is no activity for 60 seconds. Use the DWELL key again to exit the configuration mode immediately. Any changes made during configuration are acknowledged regardless of how the configuration mode is exited.
