Sony DTC-87ES Operating Instructions Manual page 29

If you record from the beginning to the middle of a tape
on which another recording has ever been applied, the
same program number may be written twice on that tape.
If you omit designating the next program number when
recording from the middle of the tape, the succeeding
program numbers are not written.
In such cases, proceed as follows to renumber the program
numbers from the beginning of the tape at a high speed.
Renumbering Program Numbers Automatically
1 Make sure that the AUTO indicator is lit, and that the
safety tab of the cassette is at the record-possible
position.
If the AUTO indicator is not lit, press START ID AUTO.
2 Press RENUMBER during playback or in the stop
mode.
The tape will automatically be rewound to the beginning,
and the program numbers are rearranged from "1" in
numerical order at each start ID position.
While the program numbers are rewritten, the START ID
indicator blinks and while the tape is fast-forwarded to the
next start ID the RENUMBER indicator blinks.
When program numbers are written correctly, the tape is
fast-forwarded to the next start ID,
(RENUMBER
"
When renumbering is terminated
The tape is automatically rewound to the beginning, and
the deck function stops.
Shifting Start IDs' and Program Numbers Position
The start ID position may not coincide exactly to the
beginning of the selection, especially when the portion
between selections is not clear. On such a tape, the very
beginning of the selection cannot be located using the AMS
function. If this happens, you can shift the start ID and
program number position, however, you cannot shift the
position of the program number 1.
1 Make sure that the AUTO indicator is off, and that the
safety tab of the cassette is at the record-possible
position.
If the AUTO indicator is lit, press START ID AUTO.
2 Press RENUMBER during playback or in the stop
mode.
The start ID and program number position of the 2nd
selection, and the succeeding selections, will be shifted
forward by about 0.3 of a second.
When program numbers are written incorrectly, the
renumber function operates.
During playback, press START ID ERASE while the
program number to be erased appears in the
display window.
That program number is erased. The start ID at the
same position will also be erased.
The ERASE indicator blinks while the program number
is being searched for, and the START ID indicator
lights while the program number is being erased.
When the program number is erased
Playback continues. The succeeding program numbers
remain unchanged. To rearrange the program numbers,
renumber them as described on the left column.
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