The Model 3170 Time Code Generator accumulates time from either an internal oscillator or an external frequency standard. When equipped with its synchronized generator option, the unit has two modes of operation; Generator and Synchronized Generator. In the Generator mode, time is presettable from the front panel and controls are provided to synchronize the unit to an external time standard such as WWV. Internal batteries maintain time accumulation for in excess of eight In the Synchronized Generator mode, the unit automatically synchronizes to a serial time code input such as IRIG B. IEEE488 In/Out RS232C In/Out Pulse Rate Outputs Sine Wave Outputs Modem Rate Outputs Other Time Code Outputs:IRIG A, E, G, H · · · · · · time@datachroninc.comwww.datachroninc.com Fax: (714) 491-8213(714) 491-8500 Anaheim, CA 928051333 South Lewis Street Multiple Rate Slow Code Output for strip chart recording. XR3/2137 AMR B1 and D5 NASA 36 and 28 Parallel Binary Outputs (several ranges and resolutions available) Parallel BCD outputs (tenths of milliseconds through days) Optional outputs include: The standard output of the unit is the IRIG B serial time code. hours in the event of primary power failure. TIME CODE GENERATOR MODEL 3170 SPECIFICATIONS Synchronizing input The Model 3170 automatically synchronizes to a time code input when in the The unit accumulates time from an internal temperature compensated crystal Synchronized Generator mode. oscillator (TCXO) or external 1MHz frequency standard as selected by internal jumpering. Format:IRIG B in the modulated carrier form (other codes are optional) Specifications for the TCXO are: Amplitude:0.1 to 10 volts, peak to peak Frequency: -6 ±1 x 10from 0 to +50°C -9 -7 Modulation Ratio:2:1 Aging Rate:3 x 10per day (5 X 10 Input Impedance:Greater than 10K ohms Specifications for the 1MHz input are: An input threshold detector can be adjusted within the range of +0.1 to +3.0 Waveform:Sine or square wave volts. If the peak value of the input falls below that level, the front panel INPUT Amplitude:0.5 to 9 volts, peak to peak LOSS LED is energized. Input Impedance:10K ohms IRIG B Serial Time Code Output Nine thumbwheel switches plus a load switch provide for the presetting of real or elapsed time into the generator when operating in the Generator mode. An IRIG B modulated carrier serial time code output is furnished at a rear panel BNC connector: Amplitude:Adjustable from 0 to 8 volts, peak to peak Generator Mode (Manual) Modulation Ratio:Adjustable from 2:1 to 6:1 When equipped with the Synchronized Generator option, a front panel toggle switch permits selection of the Generator mode (manual synchronization) or Maximum External Load:600 ohms Synchronized Generator mode (automatic synchronization). Other available outputs and control inputs are listed on the front page. The Model 3170 can be manually synchronized to an external time standard. The controls involved include a switch for selection of the advance or retard rate Detailed specifications for these options are available upon request. and switches to activate the synchronization logic. Selectable advance/retard rates are .001, .01, .1, 1, 10 and 100 milliseconds per second. Activation of the appropriate switch causes speed up or slow down of the accumulator at the selected rate. Other controls permit automatic start of the generator from an external pulse. Energization of a pushbutton switch arms the unit to start on theGenerated time is displayed by nine front panel mounted LED’s with 0.5-inch next input pulse. A lamp indicates when the generator is armed. Switches arecharacter height. included to manually start and stop the generator. Synchronized Generator Mode (Automatic) The Model 3170 operates from a primary power source of 115 volts AC ±10%, If equipped with this option, in this mode the Model 3170 accepts a 50-70 Hz and consumes less than 20 watts of power. In the event of primary synchronizing time code. If the digital contents of the incoming code differ power failure, internal Nickel Cadmium batteries maintain time accumulation from those of the Model 3170’s time accumulators, the unit refers to the for in excess of eight hours. No display or outputs are provided during power operator setting of its error bypass logic. If this logic has been programmed to failure. The batteries are continuously trickle charged when AC power is zero frames, the Model 3170’s time accumulators are immediately synchronized present. to the contents of the incoming code. If the error bypass logic has been set to a level other than zero, synchronization occurs after N + 1 discrepancies, where N is the number of frames of error bypass programmed into the unit. Once digital synchronization is attained, fine-tuning is performed to achieve The Model 3170 is designed for rack mounting. phase correlation between the 1PPS rate derived from the input code and the Model 3170’s 1PPS output. Two windows are established, one with boundariesHeight:1.75 inches (4.4 cm) at ±1 millisecond from the on time point and the second at ±100 microsecondsWidth:19 inches (48.3 cm) from the on time point. If the phase comparison indicates that the two signalsDepth:19.5 inches (49.5 cm) are greater than one millisecond apart, synchronization results in the reset of theLess than 10 pounds Model 3170’s minor time counter at the incoming time code’s reference mark. If the phase comparison indicates that the two units are out of phase by less than one millisecond but more than 100 microseconds, the Model 3170 is sped up or slowed down at a rate of 10 microseconds per second. The decision to speed up Operating Temperature:0°C to +50°C or slow down the Model 3170 depends upon whether the Model 3170 lags or Storage Temperature:-40°C to +100°C leads, respectively, the on time point of the 1PPS reference. Once the Model Humidity:0 to 95% relative, non-condensing 3170 is synchronized to the 1PPS reference to within ±100 microseconds, a one microsecond per second advance/retard (speed up/slow down) rate is used. Front panel LED’s indicate loss of the synchronizing input and synchronization One copy of an operation and maintenance manual is furnished with each unit. of the Model 3170 to the time code input to within ±100 microseconds. Manual Environmental Characteristics Weight: Physical Characteristics Power Requirements Display Synchronization Time Preset Outputs per year) to 6:1 Stability: 1MHz Frequency Standard