Tektronix 7834

Theory of Operation-7834
Matrix, Figure
3-27,
that
when row 4 is programmed, a
reduction of one
column results in a one-column shift of
the prefix . For
example, with the 100 WV program shown in
Figure 3-34, if the data
received from the plug-in called for
a shift in prefix, the crt readout
would be changed to 1 mV
(zeros deleted by program
;
see
Encoding the Data) .
The 100 microamperes of
quiescent current through R3409
provided by Q3419 (see
Display-Skip Generator) allows the
3- 4 8
prefix to be shifted from
m
(100
microamperes of column
current, column 1) to no
prefix
(0
column current, column
0) so only the unit of measurement encoded
during time-
slot 9 is displayed . Notice that reducing
the prefix program
from column 1 to column 0 programs
the Readout System
to not display a character at this
readout location .
A further feature of the Zeros Logic
and Memory is the
Identify function . If 10 units of
column current are encoded
TIME-SLOTS
Figure 3-37 . Typical output waveforms
for Zeros
Logic and
Memory
stage
operation (at pin 7 of U3401)
.