The Model 3900 Programmable Switching Unit provides the user with the ability to connect differential signals, single ended signals or time code inputs to one or more like signal type outputs. Programming of connections is made via an RS232 interface or an optional front panel keypad. Via the same RS232 interface or an optional LCD display feedback of the connections made is available to the user. The Model 3900 accepts up to 100 differential signals, up to 100 single ended signals and up to 25 time code inputs. Any one of these input types can be connected to the same output type consisting of 100 differential outputs, 100 single ended outputs and 25 time code outputs. Differential, single ended and time code signals are switched together with one RS232 All cards in the Model 3900 PSU are front loading, accessible behind hinged front panel doors. - Redundant power supplies - Top loading chassis for reduced size - Data or time code switching only - Smaller matrix size - Local control using front panel LCD display and keypad Options: front loading.The unit’s power supply is also command. In addition, the user can selectively invert data output signals. SWITCHING UNIT PROGRAMMABLE MODEL 3900 Two words are used to identify each output connection. Bit The unit houses two switching matrix types; one for switching data signals and one for switching time codes. Differential signals are converted to single ended before the 1|switching matrix and back to differential after the switch. Input and output buffers are 2|provided for both switch types. 4| __ LSB’s of output connector 8| identification The matrix used to switch differential signals can be up to 100 x 100 in size. |Specifications for this matrix and input/output buffers are: | 0| __ Identifies this word as applying Frequency Range: to an output Binary 1: +2 to +5.5 volts Binary 0: 0 to +0.8 volts Bit Input Impedance: _ 1MSB’s of output connector Switching Crosstalk:db at 100KHz 2| identification db at 1MHz 3Inverts signal Switching Speed: 40 50 6 The single ended switching matrix accommodates 100 inputs and 100 outputs. 70| __ Identifies this word as applying Specifications for the single ended matrix and its input/output buffers are: 8 to an output Frequency Range: Binary 1: +2 to +5.5 volts The transmission which requests the outputs connected to an input is configured as follows: Binary 0: 0 to +0.7 volts Input Impedance:93 ohms Bit 50 ohms Switching Crosstalk:db at 100KHz 1|db at 1KHz 2|Switching Speed: 4| __ LSB’s of input connector 8| identification |The time code matrix is 25 inputs by 25 outputs in size. Its specifications are: | 1| __ Identifies this word as a configuration Frequency Range:DC to 10MHz 10 volts peak to peak Input Impedance: Bit 50 ohms _ Switching Crosstalk:db at 100KHz 1MSB’s of input connector db at 1MHz 2| identification Switching Speed: 30 40 50 6__ 71 Identifies this word as a configuration_ The unit’s RS232 interface permits the user to connect inputs to outputs and receive8| request feedback of the programmed configuration. Specifications for this interface are: The status words returned are in the same format as the words used to program output Programmable from 110 to 19200 connectors. Data Configuration:8 data bits, 1 start bit, 1 stop bit and 1 parity bit If a parity error is detected by the PSU the transmission is not accepted and a word configured as FFH is returned. Three types of transmissions are made over the RS232 interface; select input, select output and request feedback of the outputs to which an input is connected. The words identifying an input connection are transmitted first followed by words The Model 3900 operates from a primary power source of 115 volts AC ±10%, 50 to 70 Hz identifying each output to which that input will be connected. Input identification and consumes less than 100 watts of power. Dual power supplies are optional. When so consists of two words configured as follows: equipped, the Model 3900 can operate from either supply if one should fail. Bit 11| 2| The Model 3900 is designed for rack mounting. All cards and the power supplies are 3LSB’s of input connector accessible behind hinged front panel doors. 4| identification 5| Up to 42 inches (106.7 cm), depending on matrix size. 632 _| 19 inches (48.3 cm) 70| __ Identifies this word as applying to an 19.5 inches (49.5 cm) 8 Up to 75 pounds (depending on matrix size) Bit _ Operating Temperature:0°C to +50°C1MSB’s of input connector Storage Temperature: -40°C to +100°C2128_| identification 0 to 95%, relative, non-condensing3 4 5 6 7|__ Identifies this word as pertaining One copy of an operation and maintenance manual is furnished with the PSU. 8t | to an inpu 1 _ 0 0 _ Manual 0 0 0 Humidity: |__ 64 DataWord 2 Environmental Specifications Weight: | input1 _ Depth: Width: Height: 16 8 |__ 4 2 Physical Characteristics _ DataWord 1 Power Requirements Baud Rate: 1 _ | __ _0 RS232 Interface BNCConnectors: <10 microseconds 128 _ -60 | __ 64 -80 Drive Capability: DataWord 2 5000 ohms Amplitude: | request1 _ 8 7 32 _ 6 16 5 4 BNCConnectors: 3 <10 microseconds 2 -60 1 -80 _ Drive Capability: DataWord 1 Amplitude: DC to 2MPPS | 0 _ 0 _ TriaxConnectors: <10 microseconds -60 128 _ -80 | __ 64 100 ohmsDrive Capability: 120 ohms DataWord 2 Amplitude: | 0 _ 8 DC to 2MPPS 7 32 _ 6 16 5 4 3 2 1 _ DataWord 1 Switching Matrix SPECIFICATIONS