Tascam RC-898 owner manual ABS setting, Return-to-zero, Selecting Time Mode

Section 6.4 - ABS setting

3) When the tape is at the time you want to make the “zero” point, press the CAPTURE key [29].

The current time value from the first DTRS unit will be displayed on the LOCATE TIME/VALUE display [15].

4) Press the STR key [17].

The MEMORY NO. display [14] will start to flash.

5)Press the numeric keypad’s 0 key, and then press the ENTER/LOAD key [20] to enter the current time into the 00 location memory.

The TAPE TIME display will now show 00:00:00:00, showing that it is now at zero, relative to the time you have just captured.

If the display shows something other than 00:00:00:00, this means that the tape is now at a position other than the point where you captured the time (i.e. the tape was playing or recording).

All times now are relative to this time. Any loca- tions will now be shown on the TAPE TIME dis- play relative to the new 00 memory. For example, if the relative “zero point” is set to 00:30:00:00, when the tape is at the absolute location of 00:45:00:00, the value shown on the TAPE TIME display will be 00:15:00:00 (45 – 30). However, even though the value shown on the TAPE TIME display changes, neither the actual tape position nor values shown on the LOCATE TIME/VALUE display are affected.

Absolute settings

00:00:00:00 00:45:00:00

Relative settings

00:00:00:00		00:15:00:00
.00:30:00:00	New	TAPE TIME display
	“zero”
	point

A minus value is shown on the displays either with a leading minus sign (–) on the TAPE TIME display, or with a leading period (.) on the LOCATE TIME/VALUE display.

6.3.1 “Return-to-zero”

Since the RC-898 works on time-based, rather than counter-based, references, there is no dedi- cated “RTZ” control. However, you can return to the zero point using the following procedure:

1) Press the RCL key [18].

The MEMORY NO. indicator will start to flash.

2)Press the 0 key on the numeric keypad, followed by ENTER/LOAD.

The LOCATE TIME/VALUE display will now show the actual time value of the “zero point”.

3) Press the LOC key [41].

The tape will return to the nominal “zero point” and the TAPE TIME display will show

00:00:00:00.

6.4 ABS setting

The ABS setting allows you to use the subcode on the servo track of the DTRS unit as the time refer- ence of the RC-898. Usually, this starts at 00:00:00:00, and continues for the length of the tape.

However, there are some options available with the ABS mode, which increase the flexibility of the system. These are described in 8.1.2, “Synthe- sizing timecode from ABS times”, and allow you to start with an offset, etc. when synsthesizing timecode.

6.4.1 A note on ABS frame rate

When ABS is selected, the number of frames per second is different from that in any timecode mode. For details of setting SMPTE/EBU frame rates, see 8.1.3, “Selecting a timecode type”.

Timecode (whether SMPTE or EBU) contains a fixed number of frames per second. However, the ABS method of timing works in a slightly differ- ent way.

In three seconds of time, there are 100 frames. These frames are allocated as follows:

Second	Number of	Maximum frame
	frames	value displayed
00 – 01	33	32
01 – 02	33	32
02 – 03	34	33

This pattern is repeated every three seconds, as you will notice when you set frame values using the menu system in ABS mode. When multiple DTRS units are connected together in DTRS sync mode, the master unit always outputs ABS tim- ings to the slave unit(s).

6.4.2 Selecting Time Mode

9888 Each DTRS unit in the chain capable of using timecode (i.e. DA-98 and DA-88/SY-88 units) can be changed to use either timecode or ABS timing.

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