Dolby Laboratories CP65 manual CAT no, Repeat 1 →

Page 36

4-18

A-Chain Alignment Procedures

b. Optical Preamplifier Adjustments

	Step	Action	Indication
	No.	Action	Indication
	No.

16

Cat. No.	Lt
240A
Proj. 1	Rt
GAIN	Rt
Lt
hf
GAIN
Rt
hf
Lt tp
Lt
signal
present
Rt
Rt tp
GAIN
Lt
hf	CAT NO.
Rt	CAT NO.
GAIN
hf	222
Proj. 2	222
gnd

17

FOR PROJECTOR NO. 2

REPEAT 1 → 16

4-19

A-Chain Alignment Procedures

b. Optical Preamplifier Adjustments

Notes

Reverse the Cat. No. 69 test film to play Dolby tone. Verify that the Dolby tone indication is shown on the Cat. No. 222 card (the center two green LEDs are lit for both the R and L channels). If necessary, re-adjust the Proj 1 left and right gain controls on the Cat. No. 240A card. Do not re-adjust the hf controls.

Repeat all of the above steps for projector No. 2. If you purchased a spare Cat. No. 240A card, repeat steps 15 and 16 for the spare card so it will be ready for use immediately if the occasion arises.

Image 36

Contents Model CP65 Cinema Processor Dolby Laboratories Inc Headquarters Table of Contents Section Reference Block Diagrams Introduction Page Section Equipment Required Smpte Buzz Track Stereo Optical Surround Level Cat. No Jiffy Test Film Cat. No 2 Listen . . . Film Cat. NoSection Initial SET-UP and Installation Voltage Acceptable Setting Voltage Range Fuse Type Next, check the jumpers in the following locations Cat. No , Power Supply Module Cat. No , B-Chain CardCat. No , Control Logic Card J2 NON-SYNCCP65 Backplane Standard CP65 or CP65ACP65-300 High Low Subwoofer subwoofer Output output These Modules are Necessary for Bypass Operation Slot Card Function Cat. No Two-channel NoiseReduction Module Channel DecoderContains a semi-regulated power supply with Voltage Setting Fuse Type InternationalIEC Notices HUM Problems Room lighting dimmer controls SCR-TYPEPage Section AN Overview of the Alignment Procedure Aligning the B-ChainPage Page Section Chain Alignment Preliminary Procedures Action IndicationLamp Voltage Optical Preamplifier Adjustments Chain Alignment Procedures Optical Preamplifier Adjustments 222 CAT. no Test Film Oscilloscope Traces Repeat CAT no Repeat 1 →Magnetic Preamplifier Adjustments Magnetic Alignment 100mV Section Chain Alignment Setting Room Equalization BypassLoudspeakers and Crossovers Amplifiers GeneralChain Alignment Procedures OffRepeat ActionChain Alignment Procedures Setting Room Equalization Do not adjust Paul Setting Room Equalization b. Adjusting L,C,R Gain 14 → 21 R 14 →Setting Mono Gain 79 dBCChain Alignment Procedures Subwoofer Alignment Cat. No 90 dBC 85 dBCFrom Step NoSelect format 04 Dolby Stereo A-Type Same AS 441Surround Equalization Alignment Cat. No Surround Equalization Alignment Cat. No Notes Cat. No 441Desired 88 dBC Bypass Adjustment of Surround Delay Thumbwheel SwitchMsec Setting Chain Alignment Procedures Adjustment of Bypass Gain Xx dBCFrom Xx dBC -3 dB Yy dBCAdjustment of Non-sync Gain Press the format 60 non sync switchAuto Freq Adjustment of Mono Gain and Equalization Notes Repeat page 5-20 StepChain Alignment Procedures Final Checks Press the format 04 Dolby Stereo A-type switchSection Reference Diagrams Cat. No Dual Noise Reduction Module Inputs Cat. No Optical Bass Extension and Surround Equalizer Card Cat. No B-Chain Facilities Card Cat. No Power Supply Card Cat. No Transformer Module Inputs Cat. No Control Logic Card Cat. No +24V +15V 15V +12B+15M Appendix a Checking Phasing of Speakers Appendix B Effect of Changes in Slit Height on Slit Losses Appendix C CP65M Mono Instructions OperationCat. No a Circuit Description Schematic Cat. No a Appendix D Backplane Connections List Terminal Block TB3Connector J18