Samsung CHT-350 Service Manual page 23

(3) Check Transitional Operation from RPS to Play
Check transition from RPS mode to play mode : Using a pre-recorded SP tape, make sure the entry side of enve-
lope comes to an appropriate steady state within 3 seconds (as shown in Fig. 2-19).
If the envelope waveform does not reach specified peak-to peak amplitude within 3 seconds, adjust as follows :
1) Make sure there is no gap between the supply roller lower flange and the tape.
If there is a gap, adjust the supply guide roller again.
2) Change operation mode from the RPS to the play mode (again) and make sure the entry side of envelope rises
within 3 second.
Fig. 2-19 Video Envelope Rising when Operation mode Changes from RPS to Play Mode
(4) Envelope Check
1) Make recordings on T-120 (E-120) and T-160 (E-180) tape.
Make sure the playback output envelope meets the specification as shown in Fig. 2-20.
2) Play back a self recorded tape (recording made on the unit using with T-120 (E-120).
The video envelope should meet the specification as shown in Fig. 2-20.
In SP mode, (A) should equal (B).
If the head gap is wide, upper cylinder should be checked.
(5) Tape Wrinkle Check
1) Run the T-160 (E-180) tape in the playback, FPS, RPS and Pause modes and observe tape wrinkle at
each guide.
2) If excessive tape wrinkle is observed, perform the following adjustments in Playback mode :
◆ Tape wrinkle at the guide roller S, T section : Linearity adjustment.
◆ Tape wrinkle at tape guide flange : ACE head assembly coarse adjustment.
Samsung Electronics
ENTRANCE SIDE ENVELOPE
A
Fig. 2-20 Envelope Input and Output Level
B
Alignment and Adjustments
2-15