Patch Point Connection - Pacific Research BMX-III-18 Operation And Technical Manual

BMX SERIES III CONSOLE
WARNING: Do not defeat the safety ground in any way. To do so may provide a potentially dangerous
condition to the operator.
NOTE: The DC outputs of the power supply are not referenced to the power supply chassis and,
therefore, are completely floating from the AC safety ground.
The AC mains cord should be kept away from low level audio wiring to avoid the possibility of inducing
hum into that wiring. Also, even though the power transformers were designed for very low radiated
magnetic fields, the power supply should not be placed unnecessarily close to tape playback units or
other sensitive equipment.
Console connection to the power supply is made with the supplied six foot multiconductor cable. This
cable carries only regulated DC power, and will not radiate hum into adjacent audio wiring. The cable
is color-coded, and the corresponding color names are printed adjacent to the terminals on the console
and the power supply.
Should it be necessary to install the power supply at a distance further than permitted by the supplied
cable, it is recommended that a new cable be made rather than splicing a longer length to the existing
cable. Cable lengths up to twenty feet may be fabricated using 14 gauge wire. Cables longer than 20
feet are not recommended.
It is very important to check and double-check the power supply connections prior to turn-on. An error
in wiring could result in damage to the power supply and/or console circuitry. Once the power supply
is turned on, the meter lamps will illuminate. Use an accurate DC volt meter to verify the operating
voltages at the test terminals on the front panel of the power supply.
NOTE: For information on the Redundant Power Supply Coupler Unit (PR&E #99-76), see Chapter 8.

2.6 PATCH POINT CONNECTION

Each BMX III input and output module features an audio PATCH connector. These connectors provide
the ideal point to connect external processing equipment such as equalizers, limiters, filters, etc. A
patch bay system may also be connected to provide a very flexible processing/patching facility.
The output at each patch point is unbalanced, and designed to operate into low-impedance (600 ohm
or higher) loads. The patch return is balanced, 40k ohm impedance.
The level at all patch points is -10 dBu nominal. This level was determined to provide optimum
headroom within the console as well as a good compatibility match with currently available processing
equipment. See Section 2.7 for PATCH connector pin assignment.
PACIFIC RESEARCH & ENGINEERING REVISION C
15