TEK 1725 Vectorscopes (NTSC/PAL)

Features

• Performance and Economy
• Full Frame Line Select
• Simultaneous Channel A and B Display
• Dual Filter Display
• One-button Front Panel Recall
• RGB/YRGB Display Capability
• 1730 Series Displays D-2 Servo Waveforms
• Parallax-free Internal Graticules
• Differential Phase and Gain Measurement
• Stereo Audio Phase Measurement
• Vector Center Dot Clamping
• Remote Control Capability
• Available in NTSC and PAL Standards as Well as Dual Standard
• White Phosphor Available
• SCH Monitoring Available with 1720 SCH Series Vectorscopes
• Composite Serial and Parallel Monitoring Is Available with 1730 D Series

Applications

• Cost-effective Signal Monitoring in Camera Control Consoles and Video Transmission Applications

The Tektronix 1730 Series Waveform Monitors and 1720 Series Vectorscopes provide comprehensive television signal monitoring for both NTSC and PAL applications. These versatile instruments are light weight, half-rack width and have bright CRTs for video signal monitoring. Both instruments exceed normal monitoring capabilities, and their unique features make them even more powerful when operated in tandem. Each monitor has its own advanced feature set and the proven 1700 Series family performance to provide more monitor for the money. These monitors do the job faster, better and easier at an economical price.

The 1720 Series and 1730 Series families cover a wide variety of video testing needs. For typical composite monitoring in the NTSC and PAL realm, the 1720 Series and 1730 Series more than handle the job. If there is a need for Dual Standard testing (PAL and NTSC), the 1735 Waveform Monitor and 1725 Vectorscope can be used. For SCH capability, the 1720 SCH Series of vectorscopes are an economical solution. Digital testing of both Composite Parallel and Composite Serial can be accomplished with the 1730 D Series of Digital Waveform Monitors. Whatever the individual video testing application, the 1720 and 1730 Series family provide an easy to use, economical solution.

The 1730 Series Waveform Monitor has full frame line select, with alphanumeric readout, that can be tracked by the 1720 Series Vectorscope when in Auxiliary mode. Any one or two lines of the entire frame can be selected and displayed or the same line(s) in both fields can be viewed at one time. An intensified zone in the two-field sweep and on the picture monitor output signal indicates the location of the line selection. In addition, any successive 15 lines can be overlaid for camera and VTR adjustments.

These instruments have microprocessor front panel control. They are operator-friendly and provide outstanding features in half-rack waveform monitors or vectorscopes. Both the 1730 Series Waveform Monitor and the 1720 Series Vectorscope have dual channel display capability, allowing both input channels to be displayed on the CRT simultaneously.

The 1730 (NTSC) and the 1731 (PAL) Waveform Monitor include dual filter display, which provides low pass and flat information in the same display. The 2-Field and 2-Line Display Modes have the Low Pass Filter applied to the left half of the trace. In the 1-Line Mode, the two signals are overlaid. These filter modes can also be used independently. Both versions of the 1730 Series have chroma filters centered around the subcarrier frequency.

Once the front panel has been set up in a frequently used mode, the configuration can be stored for later one-button recall. In addition, when the 1720 is used in tandem with the 1730, it will respond to this Store/Recall operation. Up to four operator-selected front panel configurations can be stored from the front panel. Four other front panel configurations are factory-programmed settings and are accessible from the Remote Control interface.

The 1720 Series Vectorscope graticule has scales for measuring Differential Phase and Gain. The Differential Phase scale has markings at 2° intervals. The Differential Gain scale has markings at 5% intervals. For even greater precision, the 1720 and 1730 Series can be coupled for differential phase measurements using the field or line sweep on the 1730 Series Waveform Monitor. The Waveform Monitor Chroma filter can be used for differential gain measurements.

Balanced inputs for the X Y mode are available on the 1720 Series Vectorscope through a separate input connector. This mode is particularly useful for evaluation of stereo audio with a special X Y graticule scale for both amplitude and phase measurements. X Y measurements can be displayed individually or in combination with a vector display. This input can also be used for other applications where X Y monitoring is useful.

The absolute and relative SCH polar displays makes the 1720 SCH series ideal for the editing suite. In the two dot absolute SCH mode, the 1720 SCH series accurately display the subcarrier to horizontal phase relationship of the input signal. In the one dot relative mode, the SCH relationship is measured against an external reference signal. This makes matched frame editing sequences easy to verify.

The Waveform Monitor can display RGB or YRGB. The RGB/YRGB staircase input is through a rear panel connector.

The 1720 Series Vectorscopes employ center dot clamping in Vector mode for easy detection of residual sub-carrier on the signal. In addition, with no signal present, the center dot automatically dims prolonging the CRT life.

Both instruments utilize post-accelerated, mesh-type CRTs equipped with internal graticules to provide parallax-free displays. Variable, evenly-illuminated scales, along with molded bezels, make waveform photography a snap.

Internal front panel presets, RGB/YRGB enable, along with front panel recall/setup can be accessed through the waveform monitor remote connector.

Both the 1730 Series and the 1720 Series are available in either NTSC or PAL versions. The 1721 Vectorscope and the 1731 Waveform Monitor are the PAL versions. The 1730D monitors digital and analog NTSC signals. The 1735 Waveform Monitor and 1725 Vectorscope provide PAL/NTSC Dual Standard Monitoring. PAL-M and PAL-N instruments are available as a modified product.

SpecificationsTek

1720 Series Vectorscopes Characteristics Signal Input (Video and External Reference)

Return Loss - >40 dB, 50 kHz to 6 MHz, power on or off.

Maximum Input - ±5 V DC + peak AC.

Loop-through Isolation - >70 dB at F_SC.

Channel Isolation - >70 dB at F_SC.

Impedance - >15 kilohm.

Upper - -3 dB point, F_SC +500 kHz, ±100 kHz.

Lower - -3 dB point, F_SC -500 kHz, ±100 kHz.

Vector Phase Accuracy - Within 1.25°.

Vector Gain Accuracy - Within 2.5%, typical.

Quadrature Phasing - Within 0.5°, typical.

Pull-in Range - F_SC ±50 Hz.

Pull-in Time - Within 1 second.

Phase Shift with Subcarrier Frequency Change - 2° ±50 Hz.

Phase Shift with Burst Amplitude Change - < 2° with ±6 dB change from nominal.

Phase Shift with Input Channel Change - < 0.5°.

Phase Change with Variable Gain Control - ±1°.

Phase Control Range - 360° Continuous rotation.

Burst Jitter - < 0.5°.

Display Differential Phase and Gain -
±1° and ±1%.

Center Dot Clamp Stability - < 0.4 mm spot movement.

Internal - Composite video with sync ±6 dB of nominal.

External Reference - Composite video or CW subcarrier.

Input - Differential, DC coupled.

Input Amplitude - 2 to 9 V p-p, adjustable full scale deflection 0 dBm to +12 dBm for 600 Ohm system, factory set to 0 dBm.

Maximum Input - ±15 V peak signal + DC.

Frequency Response - DC to 500 kHz (DC to 100 kHz high-gain mode).

X and Y Phase Match - Less than a trace width separation at 20 kHz.

Accuracy -
Absolute: ±5° phase at 25°C.
Relative: ±2°.

Acquisition Time - Less than 1 second.

CRT Viewing Area - 80 x 100 mm.

Trace Rotation - 8° range, typical.

Graticule - Internal scale with variable illumination.

Mains Voltage Ranges - 115 V, 90-132 V, 230 V, 200-250 V.

Mains Frequency Range - 48 Hz to 66 Hz.

Power Consumption - 25 watts (85 BTU/HR) maximum.

Temperature -
Nonoperating: -55°C to +75°C.
Operating: 0°C to +50°C.

Altitude -
Nonoperating: To 18,000 M (50,000 ft.).
Operating: To 5,500 M (15,000 ft.).

Shock -
Nonoperating: 30 g's, 1/2 sine, 11 ms duration, 3 shocks per surface (18 total).
Transportation - Qualified under NSTA Test Procedure 1A, Category II (30-inch drop).

Humidity - Meets Tektronix Standard 062-2847-00.

EMC - Certified to the EMC Directive 89/336/EEC.

Safety -
Approved to: UL1244, CSA231.
Complies with: EN61010-1, IEC61010-1.

Ordering Information

TEK 1725 Vectorscopes (NTSC/PAL)

When ordering, please use exact nomenclature given here. The standard instruments are shipped without a case or handle. If your application is for bench or portable use, please order the appropriate enclosure from the optional accessories list. The 1720, 1720 SCH, 1721, 1721 SCH, 1725, 1730, 1731 and 1735 are UL-recognized components and meet the requirements for listing when used in the appropriate enclosure.

1725
Vectorscope (for PAL/NTSC Dual Standard Applications).