JVC MX-G50 Service Manual

Also see for CA-MXG50: Instructions Instructions for use

Contents

MX-G50/MX-G561-26Turn off the power switch and,disconnect thepower cord from the ac outlet.Replace the pickup with a normal one.(Referto "Pickup Removal" on the previous page)Plug the power cord in,and turn the power on.At this time,check that the laser emits forabout 3seconds and the objective lens movesup and down.Note: Do not observe the laser beam directly.Play a disc.Check the eye-pattern at TP1.Finish.Maintenance of laser pickup(1) Cleaning the pick up lensBefore you replace the pick up, please try toclean the lens with a alcohol soaked cottonswab.(2) Life of the laser diodeWhen the life of the laser diode has expired,the following symptoms will appear.1. The level of RF output (EFM output:amplitude of eye pattern) will below.Is the level ofRFOUT under1.1V 0.2Vp-p? Replace it.NOYESO.K(3) Semi-fixed resistor on the APC PC boardThe semi-fixed resistor on the APC printed circuit board which is attached to the pickup is used to adjust the laserpower. Since this adjustment should be performed to match the characteristics of the whole optical block, do nottouch the semi-fixed resistor.If the laser power is lower than the specified value,the laser diode is almost worn out, and the laser pickup shouldbe replaced.If the semi-fixed resistor is adjusted while the pickup is functioning normally,the laser pickup may be damageddue to excessive current.Replacement of laser pickup