More than 10 years ago, purchased a Marantz cd63, due to its sweet and bright tone, and higher price won the my favorite. Just its head too easily broken for more than 10 years I have replaced at least 5 heads, a maximum of 3 years, the shortest for about a year. Because I was an amateur radio enthusiast, replace all her own bald head, not spending too much, put up very much at home. Each time you change heads, machine immediately to normal. Recently, however, a not so good luck. A new bald head on for two weeks without reading, the machine automatically approximately one time per second read. Business as usual for the head, but the problem remains. Didn't have a clue, and can only turn to the network. Send two days before "Marantz cd63 failing to ask", but my friends say bald was wrong. For sure, I'll change the bald.zg6service manual download site
As expected, problems still remain. It seems that this is not a common fault. I later found out each time reading action before there is a light squeaking sound. Didn't know where. Because when you put the disc, Dustin scale several times to stop no longer move, and into disc drive mechanism can't see below. I generally judge cartridge drive motor turns, katakura is in the closed position, it can no longer move, motor sliding, friction with the belts Squeak. In order to confirm and measure motor input line voltage. Sure enough, the creaking sound when the motor is getting power. I have the wiring diagram of the machine, after investigation, the machine's microprocessor reset output MN187164 of the 8th foot, usually potential was 0. Not when you put the disc, close the katakura feet after a 5-volt voltage maintained back to 0 after about 1 second. Placed into the disc closed katakura feet after short periods of high potentials and then back to 0, rising about one second after the short,zg6service manual download site
Repeatedly, and at this point is do it repeatedly reading actions. In view of this, like microprocessors on repeated reset signal, leading to repeated reading. Now is to find out why. Didn't know how to start, few want to give up, they feel aggrieved. So the free research roadmap before measuring voltages, couldn't seem to tell why. Later, I noticed that the decoder reset foot SAA7345 28 foot is turned on, and low potential to activate, if false triggering due to voltage fluctuations are too big? Because I have noticed when reading voltage fluctuates, but because the digital multimeter to see the range of fluctuation, didn't pay much attention. Then I focus observe voltage fluctuations, repeated measurements, working voltage of 5 volts minimum found only 4.5 volts, actual instantaneous voltages must still be below this value, enough to trigger circuit. Then immediately check for 5 volt power supply. The 5 v power supply of the machine from +/-10 v +10V use 7805 voltage regulator 5 v,

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