AVD-K700P
7. Adjustment after Drum Assembly (Video Heads)
Purpose of adjustment : To adjust and stabilize the height change, X-distance change, etc
depending on the guide roller after assembling the drum.
Fixtures and tools usedConnection positionVCR (VCP) statusAdjustment position
Y CH-1: PB RF EnvelopeY Play the blank tape. Y Fine adjustment of
Y Oscilloscope
Y CH-2: NTSC : SW 30HzY Play the standard test guide roller
Y Standard test tape
PAL:SW 25Hztape.Y Switching Point
(only for SP)
Y Head switching outputY Tracking Preset
Y Post Height Adjusting
pointY X-distance
Driver
Y RF Envelope output
Y Driver (+) Type ? 5
point
Checking/Adjustment ProcedureConnection DiagramOSCILLOSCOPE
1) Play the blank tape (empty tape) and check whether the
guide roller crumbles or wrinkles the tape and adjust it ifRF ENVELOPE OUTPUT POINT
necessary. CH-1 CH-2
2) Check that the RF envelope output waveform is flat, andHEAD RF SWITCHING OUTPUT POINT
adjust the height of the guide roller while playing the
W aveform
standard test tape.
3) Adjust the switching point.
4) Check the RF envelope output is the maximum whenV1/V MAX = 0.7
V1/V MAX = 0.8V1V1V2
the tracking control locates at the center. If not maxi-
RF ENVELOPE OUTPUT
mum, set up to ensure that RF envelope output
becomes the maximum by turning the (+) type driver (?
3 ~ ? 4) on the base A/C groove.
8. Check of Traveling Device after Deck Assembly
8-1. Audio, RF Normalization Time (Locking Time) Check in Play after CUE or REV
Fixtures and tools usedMeasuring standardConnection positionVCR (VCP) status
Y OscilloscopeY RF Locking Time: WithinY CH-1: PB RF EnvelopeY Play the 6H 3KHz
Y 6H 3KHz Color Bar5 secondsY CH-2: Audio outputColor Bar Standard
Standard Test tape Y Audio Locking Time :Y RF Envelope outputTest tape.
Y Stop WatchWithin 10 secondspoint
Y Audio output jack
Checking Procedure
1) Check that locking time of the RF and Audio waveform is2) Readjust the paragraph 5 and 6 if it deviates from the
fallen within the measuring standard in conversion of thestandard.
play mode from the CUE or the REV mode.
8-2. Check of Tape Curl and Jam Status
Fixtures and tools usedFixtures and tools usedFixtures and tools used
Y T-160 TapeY There must be no jam or curl at theY Travel the tape at the position
Y T-120 Tapefirst, middle and end position of tape.of its first and end.
Checking Procedureoccurrence of folding of the bottom tape. There must be
1) Check there is no abnormality of every traveling postnot abnormality of audio signal in damage of the top tape.
status. 3) If there is abnormality, readjust the adjustment para-
2) There must be no abnormal operation of the counter ingraph 4 and 5.
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