AVR400 Analogue Video Board

This is connected into the rest of the system via the HDMI board using CN301.The circuitry is shown on sheet 13 of the schematic diagram.

The purposes of this PCB are:

(1)to switch between the various analogue video inputs (comprising 4 each composite and s-video and 3 component video)

(2)to route the chosen video signal to the HDMI board for processing

(3)to provide one set of zone 1 video component video outputs

(4)to provide one zone 2 video output (composite video, with its own OSD) from any of the 4 com- posite video signal inputs.

The PCBs power supplies are +9VV and +5VV, generated from the three-terminal regulators IC88 and IC89 from the system’s +15VA supply on pin 1 of CN301. Pin 2 carries the system’s -15VA supply – this is unused on this PCB.

Note that all video inputs are terminated with 75ohm resistors to ground close to the actual sockets.

IC81 is a JRC NJW1321 – a wide bandwidth video switch with 4 inputs, 2 outputs and a 6dB amplifier. It is used to select between the 4 composite and 4 s-video inputs routed to the HDMI board and also to output any one of the 4 composite video inputs to the On-Screen Display Controller IC83. IC81 runs from the +9VV supply, consuming about 85mA so it gets quite hot. It is controlled by i2C commands on pins 15 and 16.

IC82 is also an NJW1321. It selects between the 3 component video inputs and its fourth input is unused. Its Y, Cr, Cb outputs and the Y, C and CVBS outputs of IC81 are then AC coupled to IC84 – an NJM2566 6 way video amplifier/filter with 6dB gain, powered from the +5VV rail. Its outputs are also AC coupled and terminated with 75 ohm series resistors before being routed to CN301.

IC86 is a hex inverter used to bμFfer the 3V3 logic level OSD control signals from the HDMI board and convert them to 5V level for IC83. This is a Sanyo LC74763 in a 30 pin SM package running from the +5VV rail. It has two crystal oscillators X801 (17.734MHz) and X802 (14.318MHz) to provide composite video outputs for both PAL and NTSC standards.

IC86’s video input signal is AC coupled to and bμFfered by the emitter follower Q802 before pin 18. Similarly its output signal (which now includes an OSD) is bμFfered by the pnp transistor Q801 and AC coupled to the video amplifier/switch IC85 (NJM2244), used here purely as a composite video amplifier/ filter with 6dB gain. Its AC coupled output to the Z 2 OUT single phono socket JK85 is terminated with a 68 ohms series resistor.

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Arcam service manual AVR400 Analogue Video Board
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AVR400 specifications

The Arcam AVR400 is a high-performance AV receiver designed to provide an immersive home theater experience. As part of Arcam’s esteemed lineup, the AVR400 combines advanced technology with exceptional sound quality, catering to audiophiles and home cinema enthusiasts alike.

At the heart of the AVR400 is its impressive power amplification, providing 100 watts per channel across 7 channels, ensuring a robust performance capable of driving a wide range of speakers. This power output is complemented by a high-current design, which means the receiver can handle dynamic audio passages without distortion, offering clarity in both subtle and explosive soundtracks.

One of the standout features of the AVR400 is its support for various surround sound formats, including Dolby TrueHD and DTS-HD Master Audio. This allows for an unparalleled audio experience, transporting users right into the heart of the action. Additionally, the AVR400 is equipped with the latest HDMI inputs, ensuring compatibility with a multitude of high-definition sources, including Blu-ray players, gaming consoles, and streaming devices.

The AVR400 also boasts advanced video processing capabilities, supporting 4K pass-through as well as upscaling of lower-resolution content to 4K. This makes it an ideal choice for users looking to future-proof their home theater setup, as it can seamlessly integrate with modern 4K televisions while enhancing the quality of older content.

User-friendliness is another essential characteristic of the Arcam AVR400. It comes equipped with an intuitive on-screen menu system that simplifies the setup process. The inclusion of an automatic calibration system helps optimize speaker settings in accordance with the room acoustics, ensuring users achieve the best sound possible from their setup.

Furthermore, the network features of the AVR400 allow for streaming audio from various online services and wireless devices. Built-in support for DLNA enables users to access their media library wirelessly, while the USB input allows for direct playback from flash drives or external hard drives.

In terms of build quality, the Arcam AVR400 embodies the brand’s commitment to excellence. With a sleek design, high-quality materials, and an engineered chassis that minimizes vibration and interference, the AVR400 is not only visually appealing but also built to deliver performance over time.

In summary, the Arcam AVR400 is a feature-rich AV receiver offering a perfect blend of power, precision, and versatility. Whether for movie nights or music listening, it stands out as a reliable choice for those seeking high-quality audio and video reproduction in their home entertainment systems.
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