Sharp VL-C780S Serviceanleitung Seite 168

VL-C780S/H/X
VL-C7400E
VL-C6S90S/H/x
VL-CG400E
1-6. Remaining tape alarming
1. The system clock of the microcomputer adopts 12 MHz X tal, and has better precision
compared to conven-
tional microcomputers. Therefore it does not adopt conventional remaining
tape measurement system
(Head Switching Pulse Count System), but measures the remaining tape by use
of a system clock as a timer.
2. It measures the rotation cycle of a supply reel in REC mode, and displays an alarm
when it is below the fol-
lowing (remaining tape 3 minutes or less):
NTSC SP: 2.737 sec/r, EP:7.660 sec/r
PAL SP:3.792 sec/r, LP:7.296 sec/r
it measures the remaining tape only in REC mode, not in other modes (such a recording
search and play-
back).
3. When it measures the rotation cycle of both supply and rewind reels and calculates
the actual tape thick-
ness (tape thickness correction) based upon it, it can measure the remaining tape more
accurately. Howev-
er, it does not perform the tape thickness correction since no great error occurs.
1-7. Detection of battery voltage
1-8. Recording search
STILL
Short PB (FG5)
Tension down (FG11)
1
1
REC PAUSE