W3

One of two circuit topologies may be found in a particular DC-1. The specific topology can be determined by checking if ferrite beads or 5.1 £2 resistors are installed in locations FB1 and FB2. The following table gives an indication of output voltage and drive capability for each topology.

Configuration

FB1, FB2

Min Vout

Max Vout

Max lout

+5V

ferrite beads

4.2 volts

4.7 volts

180mA

+5V

resistors

3.3 volts

5.1 volts

200mA

+12V

ferrite beads

11.0 volts

13.7 volts

100mA

+12V

resistors

11.5 volts

15.2 volts

140mA

Video Subcarrier Calibration

Required Equipment

Frequency Counter, 7 digit accuracy

1. Enter the Extended Diagnostics mode.

2. Press TV on the remote to enter the Video Test.

3. Press MENU ▼. The output frequency at TP2 on the Video board becomes the NTSC calibration frequency.

4. Set the counter to measure at a gate rate of 0.1 second and adjust the variable capacitor (C39) to set the frequency at TP2 to 3.57168MHz.

5. Press SELECT. The frequency should now be between 4.43737 and 4.43781MHz.

This will erase any programs you have stored, Restoring Defaults as well as all setup and calibration values. Note any settings you want to re-use before proceeding.

Turn the DC-1 OFF with eitherthe front panel switch or the remote. Turn the unit back ON and press and hold BYPASS on the remote while the copyright message is displayed. (Make sure you do not block the infrared receiver on the DC-1 front panel.) The on-screen display will read:

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