Bk-precision 1249B - Manual Manuel d'utilisateur Page 1

INSTRUCTION MANUAL Model 1249B NTSC GENERATOR

10 DEFINITIONS OF TERMS (CONT.) Resolution. See "Horizontal Resolution" and "Vertical Resolution"

11 THE NTSC COLOR VIDEO SIGNAL HISTORY In 1953, the NTSC (National Television Systems Committee) established the co

12 THE NTSC COLOR VIDEO SIGNAL (CONT.) horizontal sync pulse at the -40 IEEE units level. An explanation of IEEE units follows in the "Amplitud

13 THE NTSC COLOR VIDEO SIGNAL (CONT.) Fig. 2A. Compo site Video Signal Showing Vertical Blanking Interval (Field 1

14 THE NTSC COLOR VIDEO SIGNAL (CONT.) Fig. 2B. Composite Video Signal Showing Vertical Blanking Interval (Field 2)

15 THE NTSC COLOR VIDEO SIGNAL (CONT.) white. Levels between +7.5 and +100 units produce various shadings of grey. Even when a composite video si

16 THE NTSC COLOR VIDEO SIGNAL (CONT.) Fig. 3. Elements of Color Television Signal

17 THE NTSC COLOR VIDEO SIGNAL (CONT.) (saturation) set forth by the NTSC. This is the test signal used in broadcastin

18 CONTROLS AND INDICATORS 1. POWER Switch. Turns power on and off. 2. RGB TTL/LOW Switch. Selects TTL or low RGB output level. When th

19 CONTROLS AND INDICATORS (CONT.) approximately 1KHz) is included in the signal at the IF/RF output jack. When this switch is disengaged, no sound

2 TEST INSTRUMENT SAFETY Normal use of test equipment exposes you to a certain amount of danger from electrical shock because testing must somet

20 CONTROLS AND INDICATORS (CONT.) Fig. 4. Controls and Indicators

21 CONTROLS AND INDICATORS (CONT.) 19. G Jack. Provides green output signal for use with RGB monitors. Output impedance is

22 OPERATING INSTRUCTIONS WARNING To prevent electrical shock, observe the precautions listed in the TEST INSTRUMENT

23 OPERATING INSTRUCTIONS (CONT.) 4. RF Output The rf output of the NTSC Generator may be applied to a television receiver, video tape recorder o

24 OPERATING INSTRUCTIONS (CONT.) c. A calibrated 1Vp-p signal level with negative sync polarity is available when

25 OPERATING INSTRUCTIONS (CONT.) Only LINE switch engaged: A single vertical and horizontal line intersecting at the center of the screen. LINE

26 OPERATING INSTRUCTIONS (CONT.) scan. It is not compatible with high resolution graphics monitors which use special high frequency scan rates. So

27 OPERATING INSTRUCTIONS (CONT.) 2. Connect another cable from the COMP SYNC output jack to the external trigger inpu

28 APPLICATIONS NTSC COLOR BARS Versatility The NTSC color bars pattern is the basic pattern used for most testing, trou

29 APPLICATIONS (CONT.) may be exam-fined throughout the VCR for proper luminance to chroma proportions. Another problem that may be encountered is

3 TABLE OF CONTENTS Page TEST INSTRUMENT SAFETY ... inside front cover INTRODUCTION ...

30 APPLICATIONS (CONT.) SYNC The NTSC color bars and staircase pattern include NTSC sync pulses, the same type as those pr

31 APPLICATIONS (CONT.) MATV APPLICATIONS Master antenna systems for hotels, motels, apartment buildings, etc. can be checked by applying the cha

32 APPLICATIONS (CONT.) d. The display shape depends upon the chroma bandpass, demodulator alignment, and design of the TV

33 APPLICATIONS CONT.) Fig. 7. Typical Vectorscope Display of Demodulated Color Bars Pattern Viewed on Conventional

34 MAINTENANCE WARNING The following instructions are for use by qualified service personnel only. To avoid electrical shock, do not perform servi

35 MAINTENANCE (CONT.) R7 Fig. 8. Adjustment and Test Point Locations.

36 MAINTENANCE (CONT.) 3. Connect the Waveform Monitor and the Vectorscope to the COMPOSITE VIDEO jack (terminated into 75 S2). Set the Waveform Mo

37 MAINTENANCE (CONT.) 2. Press the NTSC BARS switch and release the COLOR OFF switch. Set the Waveform Monitor for a sweep speed of 1µs/div. 3. A

38 SERVICE INFORMATION Warranty Service: Please return the product in the original packaging with proof of purchase to the address below. Clearly s

39 LIMITED ONE-YEAR WARRANTY B&K Precision Corp. warrants to the original purchaser that its products and the component parts thereof, will be

4 INTRODUCTION The B+K PRECISION Model 1249B NTSC Generator is a versatile, low cost, precision television/video signal generator. It generate

40 TEST INSTRUMENT SAFETY (CONT.) (continued from inside front cover) 7. Testing "hot chassis" video-equipment is especially hazardous un

41 22820 Savi Ranch Parkway Yorba Linda, CA 92887 www.bkprecision.com © 2006 B&K Precision Corp. Printed in USA

5 FEATURES NTSC COLOR BARS Generates standard NTSC color bars pattern (eight bars of standard EIA colors) at NTSC p

6 SPECIFICATIONS PATTERNS NTSC Color Bars: White (75% or I00%. switch selectable), yellow, cyan, green, magent

7 SPECIFICATIONS (CONT.) NOTE: Specifications and information are subject to change without notice. Please visit www.b

8 DEFINITIONS OF TERMS BARS Pattern. See “NTSC Color Bars”. Back Porch. The portion of a composite video signal betw

9 DEFINITIONS OF TERMS (CONT.) Field. One-half a television picture. One complete vertical scan of the picture containing 262.5 lines. Two fields