58503BKEY FEATURESSmartClock TechnologyDesigned for R&D Labs,Manufacturing and Calibration LabsLow Cost Source for PrecisionTime and Frequency58503B GPS Time and Frequency ReceiverINTRODUCTION The Symmetricom 58503B GPS time and frequency reference receiver is a high quality source of precision time, time interval, and frequency in a lightweight compact package. The high-performance 58503B ensures excel- lent accuracy and reliabilitythe 58503B delivers precise time and frequency virtually anywhere in the world at an affordable price.When locked to the GPS signal, the 58503B provides a 10 MHz signal with an accuracy of better than 1x1012 using a 1 day average. A 1 pulse per second (1 PPS) signal with timing jitter of 1.7 volts p-p (+8 to +10dBm) into a 50 loadHarmonic distortion:2.4 volts into 50 load. (TTL compatible)Connector:BNCRise time:40 ns typicalROOT ALLAN VARIANCE458503B ADDITIONAL SPECIFICATIONSADDITIONAL FEATURESAlarm output:TTL open collector with internal pull-up resistor. Circuit can sink up to 10 ma. Provides a logic output to allow monitoring of normal (H) and abnormal (L) operation externally and remotely. BNC connector.FRONT PANEL INDICATORS (LEDs)Front panel indicators:Power, GPS lock, Holdover mode, AlarmREMOTE INTERFACERS-232C DTE configuration:Complete remote control and interrogation of all instrument functions and parameters.Factory defaults:Baud rate 9600, 8 data bits, 1 start bit, 1 stop bit, no parity. Other settings are programmable.Connector:25-pin female rectangular D subminiature on rear panel.Time code output is available to a computer immediately preceding the 1 PPS signal for the current second.NOTE 1 This specification has a 95% probability, and is based on the availability of four or more GPS satellites during three days of locked operation with a fixed antenna location. The temperature must remain within a 10 C range between 10 C and 40 C.NOTE 2 When a quartz oscillator has not been operated for a period of time, or if it has been subjected to severe thermal or mechanical shock as might be encountered during product shipment, the oscillator may take some time to stabilize. In most cases, the oscillator will drift and then stabilize at or below its specified rate within a few days after being turned on. In isolated cases, depending upon the amount of time the oscillator has been off and the environmental conditions it has experienced, the oscillator may take up to one week to reach its specified aging rate and to operate without significant frequency “jumps.”When a Symmetricom GPS receiver is initially turned on and locked to the GPS satellite system, it will achieve GPS lock within 30 minutes of operation. It has a 95% probability of meeting unlocked (holdover) specifications after 48 hours of GPS operation, followed by 24 hours of learning. The longer the GPS receiver (and its quartz oscillator) operates, the better its stability and unlocked (holdover) performance becomes.ENVIRONMENTAL SPECIFICATIONSTime and frequency reference receiver (58503B)Operating:0 C to +50 C Storage:-40 C to +80 CAntenna (58532A)Operating:-40 C to +85 C Storage:-45 C to +90 CADDITIONAL INFORMATIONPower requirements:AC power (standard)Auto ranging:100 to 127 Vac, nominal 220 to 240 Vac, nominalRanges:90 to 132 Vac 198 to 264 Vac 47 to 63 HzOption AWQ (replaces AC power operation with DC power operation)Auto ranging:24 to 48 Vdc, nominalRange:20 to 60 Vdc, greater than +23 Vdc required to startInput power (all options):35 watts (nominal)Dimensions:88.5 mm H x 212.6 mm W x 348.3 mm D Half-rack moduleQUICK CONFIGURATION GUIDE Use this quick configuration guide to easily configure your GPS antenna system. The simplified antenna compo- nent selection procedure will work very well for the majority of antenna systems. Figure 3 shows the key components which may be used in an antenna installation. Please note that this quick configuration guide works only for 58503B, 55300A, and custom GPS timing receivers which have a type-N antenna input connector. The 58533A and 58540A GPS timing receivers are covered in a separate document, Symmetricom publication number QCG/ 58533A-540A. Simple rules for placing or using the58503B GPS TIME AND FREQUENCY REFERENCE RECEIVERvarious elements of an antenna system are given beginning on page four. These rules will be referenced in each section where they apply. Installation and tech- nical support is also available from Symmetricom Global Services.ELEMENTS OF A TYPICAL GPS ANTENNA SYSTEM The following elements will be used in most GPS antenna systems: A GPS antenna (required) Cable(s) to interconnect the elements (required) Lightning arrestor(s) Amplifiers or filters: The rules will help determine if these are needed. GETTING STARTED First, determine the following: Where to place the antenna (see Rule 1to follow) Where to place the lightning arrestor if used (see Rule 3) Where to place the GPS receiver The lengths