JVC GRDVX400EK
Service Manual

2.8.2 Tape pattern check (1) Play back the compatibility adjustment tape. (2) While triggering the MAIN CN105-11PIN (HID1), observe the waveform of CN105-29PIN (ENV_OUT). (3) Confirm that the waveform is free from remarkable level-down, and entirely parallel and straight. Moreover, perform the following adjustment as required. (4) In case any level-down is observed on the left hand side, straighten the level by turning the guide roller of the pole base assembly (supply). In case any level-down is observed on the right hand side, however, straighten the level by turning the guide roller of the pole base assembly (Take-up). (5) After adjustment, try the unloading motion once, and confirm that the waveform is flat (straight) when the tape has been played back again. Moreover, perform readjustment as required. (6) When the recording has been played back again, play back the self-recording to confirm that the waveform is flat. Note: When an adjustment is performed with the lower case cover attached, first slide the Cover (M.ADJ) open and then perform the compatibility adjustment. Be sure not to damage the cover plate when sliding it open to make an adjustment because it must be re-positioned after completing the adjustment.

CN105-29 (ENV_OUT)

CN105-11 (HID1)

Fig. 2-8-3

Flatten the waveform. Misalignment of guide roller height on the supply side Misalignment of guide roller height on the take-up side

Fig. 2-8-4

2-21