Product Review (October 2004) - Sencore
VP403 Video Pro Multimedia Video Generator

Sencore has been providing technicians and engineers test equipment for decades. Their products have stood the test of time and continue to support the needs of the market. Sencore's new VP403 Video Pro is a high preformance multimedia display video generator capable of supporting a wide range of video products from conventional NTSC signals to the latest HDTV/SDTV ATSC RF and DVI interfaces. Having owned the original VP300, we find the new VP403 a more capable product for the needs of today's service technicians and calibrators. With the VP403, it is now possible to calibrate a display from virtually any of it's inputs, including the ATSC tuner thanks to the ATSC modulator built into the unit. The VP403 is a fully portable design that includes six rechargeable AA NiMH cells that get charged from the external 12VDC AC adapter. The backlit display works well in poorly lit environments, which is a typical situation when trying to properly calibrate a video display with little or no ambient light.

Display calibration has become an important part of today's serious home theater enthusiast and Sencore has responded with the VP403 video generator. The user interface on the VP403 is simple to use and follows a logical format. The user first selects the Signal Type (NTSC, Component, RGB, ATSC RF, VESA_DVI). Based on the type of signal selected the user has several Format options. Finally the Pattern menu determines the type of pattern generated by the VP403. The backlight makes it easy to see the menu items in poorly lit areas. The eight soft-keys surrounding the LCD change functionality based on the menu settings. The Gating, Test and Options buttons provide the user with additional functionality.

Interface Panel
The connector interface panel on the VP403 is loaded with a variety of video connections. The DVI-I connector is used not only for digital video, but for analog component and RGB video as well. Sencore provides a DVI-to-RGB/HV cable, a DVI-to-DVI cable and a DVI-to-VGA cable for this interface. The DVI-to-RGB/HV cable is also used for testing component video. Also included are composite, s-video, NTSC RF and ATSC RF video connectors. Sencore supplies five BNC-to-RCA adapters for the BNC cables to mate to consumer RCA connectors. An RS232 port can also be used to control the unit. The USB port is used to update firmware in the VP403, yet we never used it. There is also a 3.5mm stereo audio output jack that generates 1 kHz and 2 kHz tones. The power jack recharges the NiMH batteries and can also be used while running the unit during lengthy tests.

Test Patterns
The VP403 has an extensive number of test patterns that are essential for performing proper calibration on today's high resolution displays and projectors. Practically every interface can now be calibrated properly with the VP403 assuming the display device supports it. These are the patterns available in the VP403.



Anamorphic 4:3

Used to check the accuracy of a display device’s anamorphic stretch feature. Circular patterns should appear circular and not oval. Linearity can also been seen here as all circles should look correct.


Used to check the high voltage regulation of CRT power supply circuits. Poor regulation results in trapizoidal looking pattern instead of retangular patterns. This is also usefule for checking ringing of the video signal as the signal transistions from black to while or vice versa.

Color Bars

This pattern helps determine the display’s capability to produce fully saturated primary and secondary colors.


The Convergence pattern is something new to the Video Pro 403 and offers calibrators a different pattern for adjusting the display's color converge. Each color should form a straight line and be of equal width. The user can also use the gate menu to turn on/off any of the colors. Traditionally calibrators solely relied upon the standard crosshatch pattern, but this was sometimes difficult to use because the color blue was not easy to see. However, this pattern works well at detecting any fringing that may be occuring on the display.


Both 4:3 and 16:9 Crosshatch patterns are also included for those who prefer to converge the image with the traditional patterns.


The color decoder pattern called DecodAdj is used to adjust the display’s color decoder/matrix circuit for most accurate color reproduction.


Use to check the color decoder performance to determine if the decoder over-emphasizes red or green colors.


Use to view the effects of focus adjustments across the entire screen.


Use to set the contrast and brightness controls on fixed-pixel (non-CRT) displays.

Horizontal Staircase (H Stair)

Use to visually check grayscale tracking performance of a rear projection display.


Use for deflection linearity testing and alignment.


Use to check a display’s ability to produce sharply defined stripes, at equal brightness, up to the format’s full resolution.


Use to detect whether scan velocity modulation (SVM) is enabled on a display device.

(16:9 also included)

Use to check and adjust for the proper geometry of a display, including picture centering, size, trapezoid (keystone) correction, pincushion (bow) correction, and linearity.


Use to set the picture black level and check the DC restoration (black clamping) performance of a display device.


Use to check the digitizing linearity of video signal processors.


Use to check color purity and display chrominance uniformity.


Use to check the regulation of CRT high-voltage and deflection power supply circuits.


Use to align display sharpness, picture, aperture, and scan-velocity modulation (SVM) adjustments.


Use to adjust color and hue through a blue filter with composite, S-video, or YPbPr signal inputs.


Use to visually check grayscale tracking performance of a display.


Use the white window at a high IRE to calibrate display drive chromaticity.


Use the white window at a low IRE to calibrate display cutoff chromaticity.

VP401/403 Optional HDCP test

Works with any pattern to test (copy protect) HDCP compatibility.

The VP403 is the most comprehensive video generator for serious calibrators that need to perform professional video calibrations with an easy to use interface. The VP403 has the unique ability to modulate video signals per the ATSC standard to give calibrators the abiliy to adjust out differences in the digital tuners. This is something not found on most of the video generators we have seen. They can also be updated with the latest firmware using the serial interface through a PC. Priced at $4,995, the VP403 is a serious tool for ISF calibrators and the price reflects this. They also offer the VP401, which is basically the same unit without the ATSC output for $3,995. Either way, these generators wil pay for themselves over time doing calibrations. We have used them in the field and for product reviews and they have never have let us down.

- Kevin Nakano

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