Grass Valley Performer SD - Manual (Page 27)

1-7
Functional Description
the state of the three “breakaway” buttons (V, AES1, and AES2).
The Performer is capable of full breakaway operation, meaning
that video may be separately switched from audio and even the
two audio channels may be separately switched one from the
other.
The microcomputer writes to the displays over an 8-bit parallel
bus. The appropriate display is enabled by a driver output from
the VAA board to accept the source number data.
Power Supply Board
The automatic switchmode Power Supply board delivers +5VDC
to the VAA main board. A step-up converter provides +15VDC
necessary for remote operation and for lighting the front panel
LEDs. Input power may be 100 to 240 volts. The AC line cord is
hardwired to the frame and is UL or TUV selectable at time of
original order.
The AC input is fused but is not user serviceable. This fuse is
soldered onto the power supply circuit board and is accessible to
a qualified service person only by removing the top cover.
Tally Board (option)
The optional Tally board mounts 10 relays and 13 opto-isolated
inputs. The 10 relays are slaved to the video selections made by
the switcher operator. When a video source is selected, the
corresponding relay closes (only a dry contact relay closure is
provided). The opto-isolated inputs provide a connection point
for a Joystick Override or other remote control device.