The HP Model 10544A Quartz Crystal Oscillator is an calibration necessary to stay within FCC accuracy extremely stable, compact, low power, source of 10 requirements. MHz. Fast warm-up and low aging are important for The 10544A is ideally suited for use in communication both instrument and systems applications. This is achieved using a new crystal design ruggedly mounted and navigation systems, synthesizers, time-code gener- in a cold-welded enclosure. The crystal, along with the ators, counters, and spectrum analyzers. The 10 MHz oscillator, buffer amplifier, and oven control circuits output frequency is a convenient starting point since it are all mounted inside a thermally insulated oven. is easily divided or multiplied. A screwdriver adjustment through the top of the oven Model 10544A is designed to mate with standard 15- enclosure permits frequency adjustment over a range of pin printed circuit board connectors which permit direct 4 x 10-6 (40 Hz), yet the control is sensitive enough to connections and elimrnates the need for separate allow adjustment to better than 1 x 10-9 (0.01 Hz). sockets and interwiring. The 1000-0hm output imped- Frequency can also be controlled electronically over a ance satisfies most solid-state input requirements. 1 Hz range with an externally applied voltage. Its unique design features, plus production efficiencies enable HP to offer, inexpensively in the 10544A, the To permit optimum performance and use of available better than 5 x 10-1°/day aging formerly available only voltages, the power inputs for the oscillator/amplifier, in expensive laboratory type oscillators. With this low oven controller and oven circuits are available sepa- aging rate of less than 1.5 x 10-7/year the manufacturer rately. However, with a simple external IC regulator a of communication and test equipment can offer his cus- single voltage regulated to 10 percent may qe used. tomers a .real cost saving by reducing the frequency of I SPECIFICATIONS ..TEMPERATURE COEFFICIENT: <1 x 10-B frequency FREQUENCY: 10 MHz.(1) change over a -55° C to 71° C temperature range. ~ AGING RATE: <5 x 10-1°/day after 24-hour warm-up.(2) <3 x 10-9overOto71°C range. and <1.5 x 10-7/year. LOAD:<5 x 10-10 frequency change for2500hm load change SHORT TERM STABILITY: WARM UP: Within 5 x 10-9 of final value 15 minutes after 1 x 10-"/1 s Avg. time. turn-on, at 25°C(3) 1 x 10-"/10 s Avg. time. 2 x 10-1'/100 s Avg. time. ..INPUT VOl TAGES/VOl TAGE COEFFICIENTS: Voltage Coefficients Required Input Circuit Required Voltage Current/Power Voltage Change Frequency Change Oscillator/ Amplifier 10.6-11.7 Vdc 15 mA <5 x 10-'0 1% Noise <100 ,uV Oven Controller 10.6-11.7 Vdc 5mA 10% Oven <1 x 10-10(4) 15-30Vdc Turn-on load is 50- Ohms. Power drops to 2'!2W at 25° C after 15 minutes. NOTE See Input Voltages section for details concerning use of common power supplies ..ENVIRONMENT AL: ..ADJUSTMENT: Temperature, operating -55° C to +71°C. ~ Coarse Frequency Range: >j:2 x 10-6 from 10 MHz with Temperature, storage -55°C to +75°C. 18-turn control. AltItude: 50,000 feet (15,2 km). Electronic Frequency Control (EFC): ~1 x 10-7. control range -5 Vdc to +5 Vdc. Humidity: 95% AH at 40° C. CONNECTORS: Vibration: 0.01 " peak-to-peak, 10 to 55 Hz. Printed circuit -Mates with CINCH 250-15-30-261 (HP WARRANTY: 1251-0159) or equivalent. Hewlett-Packard warrants the 10544A 10 MHz Oscillator OUTPUT 10 MHz: against defects in materials and workmanship for a period of 1 year from the date of delivery. The oscillator will be Voltage: 1V rms :!:20% into 1000 Ohms from ac coupled repaired or replaced at the factory at no charge during the ( .01 I1F) emitter-follower . warranty period. Harmonic Distortion: Down more than 25 dB from rated SIZE: output. Nonharmonic Components: Down more than 80 dB from 2-3/4" x 2-1/32" x 2-7/16" (13.6 cu. in.), (6.985 x 5.159 x rated output. 6.191 cm) (see Figure 1). Signal-to-Slngle-Sldeband Phase-Noise Ratio: (1 Hz WEIGHT: Measurement Bandwidth). 11 oz (0.31 kg). Offset from Ratio (dB) 10 MHz (Hz) 10 115 100 120 125 1,000 130 10,000 ~ ~ . INDt.CAJESOHANGESFR9MPR.I!iii~$peCrFICI\TI0NS ~ Table A INSTALLATION: Pin 1: 10 MHz Output. The 10544A 10 MHz Oscillator may be mounted into a Pin 2: Ground 15-pin printed-circuit connector in any convenient Pin 3: +10.6to11.7Vdc. Oscillator/Amplifier position. The oscillator is secured with 6-32 machine Input (15 mA nominal). screws and lock washers using the two threaded mount- Oscillator/Amplifier and 10 MHz Signal Pin 4 ing studs on its base (see Figure 1 ). Ground. : EFC Ground (tied internally to pin 4),* Pin 5: ': EFC Input (Control range -5 to +5 Vdc),* Pin 6: '. NC Pin 7: Pin 8: I: +10.6 to 11.7 Vdc, Oven Controller Input (5 mA nominal). Pin 9: I: Oven Controller Negative. Pin 10: 10: NC 11: Oven Monitor Pin 11: Pin 12: 2: NC Pin 13: 3: NC 4: +15 to 30 Vdc. Oven Power Input, (Turn- Pin 14: on load is 50-Ohms. Power drops to 2Y2W at 25°C after 15 minutes). Pin 15 15: Oven Power Negative. "Connect Pin 5 to Pin 6 if external EFC control is not used. INPUT VOlTAGES: The oscillator-amplifier and the oven controller (pins 3 and 8) may be connected to the same 10.6 to 11.7 Vdc source. However, to isolate controller switching- transients from the oscillator, the following LC circuit is recommended: FIGURE 1 Outline Drawing CONNECTIONS: ~~~~~ '\..~~ ~~~~ ~~~~""' ~~ ~~~ *'-~~'-!:..~~ ~ 1.-.~ pin printed-circuit Connector, such as CINCH 250-15- .30-261 (HP Part No.1251-0159). Connections are FIGURE 3 shown in Figure 2 and listed in Table A. Decoupling Filtel r- FIGURE 2 Block Diagra/T OVEN MONITOR: put voltage or frequency is not within specification, An output signal is available at pin 11 which indicates check the input voltages and determine that the the temperature condition of the oscillator oven. The regulation and noise are within specific-ation. If the signal voltage level depends on the value of oven supply input power or current are substantially different from voltage at pins 14 and 15. those shown in Table A, return the oscillator to HP for Duty-cycle of the signal at pin 11 depends on the oven repair. The oven input power should decrease within a temperature; long duty-cycle at turn-on and short few minutes after turn-on as the oven temperature duty-cycle at operating temperature. The corre- stabilizes. Continued full input power indicates a mal- sponding dc voltage monitored with a high-impedance function of the oven controller and will damage the voltmeter is; maximum voltage level when the oven is oscillator by overheating. cold (at turn-on) and minimum voltage level when the oven is at operating temperature. SERVICE: The 10544A is designed for factory repair and field OPERATION: repair should not be attempted. Repairs are handled promptly on an exchange basis through the nearest HP Connect the oscillator through a 15-pin printed-circuit Sales and Service Office. connector. Allow a 24-hour warm-up time for stabili- zation before adjusting frequency. VOl TAGE SOURCES: FREQUENCY ADJUSTMENT: Since the Oscillator/Amplifier and EFC circuits are not Oscillator frequency may be adjusted within a range of tied internally to the Oven Controller and Oven circuits, 4 x 10-6 (40 Hz) by using the 18-turn screwdriver ad- the voltage to supply the oven may have either a justment located on the top of the oscillator case. Fine positive or negative ground or be a combination of frequency adjustments may be made within a range of sources to give the required 15 to 30 Vdc. The positive ~1 x 10-7 using -5 to +5 volts dc as a tuning source. Oven voltage must be at least two volts above the positive Oven Controller voltage. A simple method of frequency adjustment is the "oscil- " loscope drift" method. The oscillator frequency may i be adjusted against a reference or "house" standard and drift can be monitored. 15 -30 VDC ..Oven (14) Methods for measuring frequency are described in 8.2 n To Oven Section III of HP Application Note 52. For minimum , , ..Controller ~ ~ 6(~ " (8) , 8 1( distortion the oscillator output should be terminated jlA723C IOmH 7 with a 1000-0hm load. < 3.83K ( -To 5 9 S 1% ~°sc/Amp 10llF (31 Aging and StabIlIty Measurement: T '-i/--4 lOOpf 6.81K ~ 1 1% th Refer to HP Application Note 116 and Computing Counter Applications Library for information on methods of making precise aging and short-term stability measurements of the Model 10544A Oscillator. FIGURE 4 Operational Tests Voltage Regulator using Fairchild jJ.A723C, (HP Part No.1820-01961 TO5 Configuration Apply the proper input voltages and allow the output frequency to stabilize for 24-hours. Adjust the output frequency to 10 MHz as described under FREQUENCY A source of +15 to +30 Vdc with 10 percent regulation ADJUSTMENT and check the output voltage with an RF Voltmeter or calibrated oscilloscope. Be sure to may be used as a power source if a simple IC regulator terminate the output with a 1000-0hm load. If the out- is used. A suggested circuit is shown in Figure 4. ~ For more information, call your local HP Sales Office or East (201) 265.5000 .Midwest (312) 677-0400 .South (404) 436.6181 West (213) 877-1281. Or, write: Hewlett-Packard, 1501 Page Mill Road, Palo Alto, California 94304. In Europe, 1217 Mevrin.Geneva Printed in USA £# 02-5952-0751 ~