Axcera-430B FCC Type Acceptance Report Parts List/Tune-up Info
February 2004
7-15
1.
To align the ALC board, preset the following controls on the tray:
A. ALC Board (1265-1305)
Connect jumper W1 on J4 to Disable, between pins 2 and 3 (to disable linearity
correctors). Connect jumper W3 on J6 to Manual, between pins 2 and 3 (for manual
gain control).
Adjust R87, the manual gain pot, to mid-range.
B. IF Phase Corrector Board (1227-1250)
Move W2 on J9 to Phase Correction: Enable. Move W3 on J10 to Amplitude
Correction: Disable.
2.
The combined IF output of the sync tip clamp/modulator board is cabled to jack J32
of the ALC board. Remove J32 from the board, and look to see if DS1, the Input
Fault LED, is illuminated. Reconnect J32 and make sure that DS1 is extinguished.
3.
Jumper W3 on J6 should be in the Manual position. Monitor jack J3 with a spectrum
analyzer.
4.
With a multiburst video signal present, tune C4 for a flat-frequency response of
±0.5 dB.
5.
Before proceeding with the second part of the ALC board alignment, check to see
that the IF phase corrector board (1227-1250) is functioning properly.
7.2.12.9 IF Phase Corrector Board
See Section 7.2.4 of this chapter for the system alignment procedures for the IF phase
corrector board. The signal level into the board should be approximately the same as the
output of the board.
The IF input jack of the IF phase corrector board is fed from J3, the IF O/P jack of (A8)
the ALC board. The IF output jack of the IF phase corrector board is fed to J7, the IF I/P
jack of (A8) the ALC board.
7.2.12.10 ALC Board, NTSC (Part 2 of 2)
To align this board:
1.
Input a multiburst video test signal. Connect a spectrum analyzer to J11. Tune C63
for a flat-frequency response of ±0.5 dB.
2.
Move the Operate/Standby switch on the front panel to the Operate position.
3.
Place jumper W3 on jack J6 in the Manual mode and adjust R87 for 0.5 volts at TP4.
4.
Place jumper W3 on J6 in the Auto mode and adjust the front panel power adjust
control A20 fully CW. If the (optional) remote power raise/lower kit is present, then
adjust switch S1 on the board to maximum voltage at TP4. Adjust R74, the range
adjust, for 1 volt at TP4.
5.
Tune front panel power adjust control A20 for 0.5 VDC at TP4. If the (optional)
remote power raise/lower kit is present, move switch S1 on the board to mid-range
and then tune (A20) the front panel power adjust control for 0.8 VDC at TP4.
Summary of Contents for 430B
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