The Tektronix 1420 is a vectorscope instrument designed for NTSC 525/60 video systems that displays and analyzes chrominance information within composite color video signals. It presents saturation and hue data in polar-plot format on a CRT display, where radial displacement indicates saturation amplitude and angular displacement represents hue phase relative to the color burst reference. The instrument serves broadcast engineers, video editors, and technicians requiring precise color signal characterization during production and transmission monitoring.
Technical Specifications
• Video Standard: NTSC, 525/60 scan TV systems
• Display Format: Polar-plot CRT presentation of chrominance, saturation, and hue
• Input Configuration: Dual video inputs with Channel A attenuation capability; front-panel A/B channel selection
• External Reference: Subcarrier reference input provided
• Gain Control: Calibrated detent position with CAL indicator lamp; UNCAL indicator present
• Phase Control: Continuous adjustment through 360° range (uncalibrated)
• Measurement Accuracy: Differential gain and phase errors determinable to within 5% and 2° respectively
• Test Feature: PUSH-TEST CIRCLE function for horizontal/vertical gain matching and quadrature phasing verification via subcarrier regenerator unlock and 180° phase switching
• Graticule: Parallax-free internal design optimized for vector displays; illuminated for photography
• Physical Format: Half-rack width, 5.25 inches vertical height; compatible side-by-side mounting with waveform monitors
– Key Features
• Variable sensitivity control for signal adaptation
• Front-panel operation and control accessibility
• Differential gain/phase measurement capability within specified tolerances
• Compact form factor designed for broadcast console integration
– Typical Applications
• VTR monitoring and calibration
• Camera control unit setup and verification
• Video production color signal analysis
• Post-production monitoring and quality assurance
– Compatibility & Integration
The 1420 integrates with NTSC-based video workflows. Related PAL and PAL-M variants (Models 1421 and 1422) serve alternative broadcast standards. The instrument’s compact half-rack width permits direct side-by-side mounting with the Tektronix 528A waveform monitor for dual-parameter signal analysis.
