Tektronix DAS9100 User Manual

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Service Administrative Support
7Ll4 A48A5 01755 REPLACEMENT
RE: M50713
On the Sununing Amplifier and 2nd
LO Error Amplifier Board A48A5, if
the -15V supply comes up before
the +15V supply, the current limit
in A48A5 01755 is disabled and the
microcircuit (P/N 156-0067-12)
becomes inoperative.
To prevent the destruction of
A48A5 01755, A48A5 Cl755 was
replaced with a luf capacitor and
a lOOohm resistor was added in
series with the -15V line to A48A5
01755.
If field replacement of A48A5Ul755
becomes necessary, parts
replacement kit 050-1781-00 will
provide the new microcircuit along
with parts and instructions for
installing the mod.
w2 Issue 13-16
50M40 WRONG RESPONSE TO •CONFIGURE?•
COMMAND
Serial Number: 8010100 to 8010310
Reference: UllOl
To correct for a possible erroneous
response to the CONFIGURE? query over
the GPl8 buss UllOl was reprogramed.
The new part number for UllOl is
160-1479-01.
w2 Issue 13-19
401X OPTION 22/23 INSTALLATION/REPLACE-
MENT CHANGES
REF: 021-0201-00/01 2741 Correspon-
dence Code Interface Service
Manual, p.n. 070-2280-0X
Reports have come in from the field of
the Option 22/23 interface being DOA on
installation. This would normally show
-13-
October, 1883 laaue 31
as continual erasing of the screen
after initial powering up and pressing
the page key. Turning power off and
then back on will not clear the problem
in most instances.
Investigation into this phenomenon has
found a firmware abnormality caused by
changes to the CMOS RAM mask. This
firmware abnormality will not be fixed.
The reason for this failure mode has
been found to be incorrect initial-
ization and set up parameters written
into the CMOS RAMs by virtue of the
particular way the CMOS RAM initially
powers up.
To work around this, the installation
and replacement procedures must be
changed. Any time the Processor board
is installed or replaced, the battery
backup must be disconnected before
powering up the interface. This is
easily done after installing the
interface by disconnecting JllO on the
processor board, powering up the
terminal, typing page, and then
reconnecting JllO (without powering
down) onto the Processor board. This
procedure will ensure that the menu
comes up and set up parameters can be
set correctly without hanging the
terminal in an erase mode.
If a unit requires service because it
constantly pages when the terminal is
turned on and paged, first, turn off
the terminal and disconnect JllO from
the Processor board. Wait at least
one minute for a 11 vo 1 tage potential
to drain off, then power up. If the
menu does not come up, type Break 1.
If the menu still does not appear,
then there is probably a problem with
the Processor board. If the menu
comes up, then check the battery. It
may be the cause fa the problem.
Normal battery voltage .should be
be approximately 2.9 volts.
w2 Issue 13-16

Tektronix DAS9100 Specifications

General

Brand	Tektronix
Model	DAS9100
Category	Measuring Instruments
Language	English