Tabor 8020, User Manual

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3-14-2. Recall Set-ups
The model 8600 employs a non-volatile memory
(RAM). The computer circuit continuously monitors
front panel traffic and saves it in a special location within
the RAM. This location is separate to the stored front
panel set-ups. After turning AC MAINS off or in case of
an accidental power failure, the generator will update
front panel indicators with the last set-up before power
shut-down.
To recall a front panel set-up proceed as follows:
1. Depress in sequence the [2nd] and [RCL] push-but-
ton and observe that the display is modified to indicate the
following:
C xx
“C” means that the instrument is placed in recall mode.
“xx” indicates the number of the present storage cell.
Numbers may range from 00 to 30. Depressing [2nd] re-
moves the generator from recall set-up mode and leaves
front panel settings unchanged.
2. Recalling a specific front panel set-up is done by de-
pressing the MODIFIER [x1 UP] or [x1 DOWN] until
the desired cell number is displayed. Depressing [EXE]
updates front panel set-up with those parameters stored
in the recalled memory cell.
3. Repeat the above procedure for as many set-ups that
are required. Recalled front panel set-ups are limited to
30.
3-14-2-1. Using The Recall Mode
Model 8020 employs a special recall mode which per-
mits ascending or descending scrolling through a
number of set-ups by pressing either the MODIFIER [x1
UP] or [x1 DOWN] push-buttons respectively. This
mode is especially useful for repetitive procedures such
as calibration and performance tests.
To set the function generator for operation in the recall
mode proceed as follows:
1. Depress the [2nd] push-button and observe that the
display is modified to indicate the following:
2nd ?
? appears flashing
2. Depress the [RCL MODE] push-button (second func-
tion to [x1]) and observe that the display is modified to
indicate the following:
C 00
The instrument is now set to operate in its recall mode.
The display is first updated with the parameters which
were stored in memory cell 00.
3. Use the MODIFIER [x1 UP] or [x1 DOWN] for scroll-
ing through the memory bank.
4. Depress [EXE] to exit this function and to return to
normal display operation.
3-15. USING THE OFFSET
When setting the offset parameter, the user must keep in
mind that the offset is attenuated with the signal. The
function generator utilizes 3 post amplitude attenuators
of which 2 attenuate the signal by 20dB and one attenu-
ates by 10dB. There is also a 10dB pre-amplifier attenu-
ator. Ranges are internal to the instrument and are auto-
matically selected with the required amplitude level.
This may cause some confusion since the operator has no
access to selecting an attenuator. Also, not knowing this
fact may cause an offset error at amplitude values that
seem to be reasonable. As stated before, offset is ampli-
tude dependent. It is therefore suggested to first set up
the amplitude and offset parameters independently and
only then to place the generator in offset mode. Offset
and amplitude are independently selectable within the
limits given in Table 3-2.
To place the function generator in an offset mode, de-
press the [2nd] push-button and then the [OFST] push-but-
ton. If the selected offset-amplitude parameters are within
the specified windows, the OFST light illuminates; indi-
cating that the offset mode is now active. Repeating the
sequence of depressing [2nd] and [OFST] turns the light
off and places the instrument in its normal mode of opera-
tion. The selected waveforms will then be symmetrical.
3-16. CHANGING THE GPIB ADDRESS
GPIB address is modified using front panel program-
ming therefore, conventional address switches are not
provided. The non-volatile memory stores the GPIB ad-
dress. Detailed instructions how to change the GPIB ad-
dress are given in Section 4.
Operating Instructions Model 8020
Page 3-12