A camera scene target, electronic search like on scene image is normal, that the camera part of the output video signal is normal, the preliminary judgment fault is part for VCR tape running bad or drum motor, main shaft motor due to bad. In order to quickly determine the fault in part, to connect the power switch, a closer examination reveals on the power switch immediately appear on electronic search like noise, noise band disappear automatically after 3 seconds, according to the "fast forward" or "back" button, the noise band appeared immediately, press the "stop" key after noise disappear, press "out of box" noise band also appears, with warehouse after pop noise disappear, illustrate the failure phenomenon related to main shaft motor rotation (this is due to the switch power supply is connected in an instant, if take positions inside the box, systems and control microprocessor location condition and with warehouse inspection instruction, main axis motor rotation, according to the "fast forward" or "back" button, the main shaft motor drive belt volume, "out of box" button. Main shaft motor drives the take-up box with volume will pop-up box. Visible, in the above three kinds of working state, drum motor does not turn, only the noise with rotation, so the fault phenomena associated with noise with rotation). With A/V cables connect the camera and monitor, press the "replay" button, monitors the image on the surface of noise, but the audio signal basic normal, check the tension arm of cassette tape path, loading arm, A/C head and pressure roller found no abnormalities, without doubt is dominant axis smudgy. Main shaft motor rotor, discharged with industrial alcohol after axle housing and shaft surface cleaning of the collar add a drop of oil clock, improve child, turn the rotor by hand is normal, according to "replay" button, the failure phenomenon still exists, estimate the fault in the main shaft power loop, as shown with a multimeter to check the circuit transistor Q1062 collector of voltage, found no obvious problems (stop state, replay of 4.5 V, 12.5 V fast forward/rewind, 10.5 V), in the state of the replay with a 47 u F / 25 V electrolytic capacitors in parallel on both ends of C1O64, electronic search like noise on the device immediately disappear, low-pass filter capacitance C1064 has failure. Replacement C1O64, troubleshooting.

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