cables will help to ensure more reliable and consistent intercom system performance. The differential (“balanced”) 4-wire circuits are typically not impacted by the length of their interconnecting cables. A final location criterion is to provide access to the Model 45’s front panel. An optimal location will allow convenient use of the auto null push- button and easy observation of the level meters and status LEDs.
Protecting the Enclosure
The Model 45 is shipped as a self-contained unit suitable for portable use. Included with the unit are self-stick “bump on” protec- tors. These may be applied to the bottom corners of the unit if it is going to be placed on surfaces where scratching of either the Model 45 or the surface could take place.
Rack Mounting the Model 45
For permanent or mobile applications it’s possible to mount one or two Model 45 units into one space of a 19-inch rack enclosure. Two rack-mount front panels, purchased separately, are available from Studio Technologies. Refer to Figure 3 for details.
The following provides details on how to install and use the panels. To attach a Model 45 unit to a single-unit rack-mount
front panel, begin the process by remov- ing the five screws that hold the standard “throw-down” front panel to the Model 45’s chassis. Using a Phillips screw driver, remove the 4-40 flat-head Phillips-head machine screw which is located in approx- imately the center of the front panel. Then use a 5/64-inch hex wrench to remove the four 4-40 button-head hex machine screws. Save the screws and carefully protect and store the standard front panel for possible later use. Using the screws that were just removed, attach the rack- adapter front panel to the Model 45’s chassis. To prevent damage extreme care is required when aligning the front panel with the LEDs, DIP switch assembly, and auto null pushbutton switch that protrude through the Model 45’s chassis. Tighten the screws only after careful inspection, ensuring that all protrude through the front panel without interference. The center (Phillips-head) screw should be tightened first, then tighten the remaining four.
The dual-unit rack-mount panel follows the same procedure but applies to two Model 45 units. Store both of the removed “thrown-down” front panels for possible later use. Note that on the front-panel graphics one unit is designated as A while the other B. This is provided so that each can be easily identified during installation, troubleshooting, and operation.
Figure 3. Model 45 shown in optional single-unit and dual-unit 19-inch rack-mount panels
Model 45 User Guide | Issue Preliminary 2, March 2009 |
Studio Technologies, Inc. | Page 11 |