Tektronix VM700A VMTB User manual

Instructions
050-3302-02 and above
Acquisition Board Replacement
VM700A and VM700T
075-0301-02
*P075030102*
075030102
Warning
The servicing instructions are for use by qualified
personnel only. To avoid personal injury, do not
perform any servicing unless you are qualified to
do so. Refer to all safety summaries prior to
performing service.
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Copyright ©Tektronix, Inc. All rights reserved. Licensed software products are owned by Tektronix or its subsidiaries or
suppliers, and are protected by national copyright laws and international treaty provisions.
Tektronix products are covered by U.S. and foreign patents, issued and pending. Information in this publication supercedes
that in all previously published material. Specifications and price change privileges reserved.
TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.
Contacting Tektronix
Tektronix, Inc.
14200 SW Karl Braun Drive
P.O. Box 500
Beaverton, OR 97077
USA
For product information, sales, service, and technical support:
HIn North America, call 1-800-833-9200.
HWorldwide, visit www.tektronix.com to find contacts in your area.

Acquisition Board Replacement 1
Service Safety Summary
Only qualified personnel should perform service procedures. Read this Service
Safety Summary and the General Safety Summary before performing any service
procedures.
Do Not Service Alone. Do not perform internal service or adjustments of this
product unless another person capable of rendering first aid and resuscitation is
present.
Disconnect Power. To avoid electric shock, switch off the instrument power, then
disconnect the power cord from the mains power.
Use Care When Servicing With Power On. Dangerous voltages or currents may
exist in this product. Disconnect power, remove battery (if applicable), and
disconnect test leads before removing protective panels, soldering, or replacing
components.
To avoid electric shock, do not touch exposed connections.

Service Safety Summary
2Acquisition Board Replacement

Acquisition Board Replacement 3
Kit Description
This kit provides instructions for replacement of the Acquisition board in
VM700T or VM700A Video Measurement Sets with or without the VMTB or
VMTX Turbo upgrade installed. This kit provides parts to preserve EMI
suppression. This kit includes: an Acquisition (A18) circuit board, an EMI
right-side bracket, a finger-clip shield for the I/O CPU (A20) board, and
installation instructions. The part number of the Acquisition (A18) circuit board
changed in this modification.
These instructions support Tektronix modifications: M86119, M88976, and
ECO1087.
Products
VM700T
VM700A with or without VMTB or VMTX installed
Minimum Tool List
HPozidriv screwdriver, P2
Kit Parts List
Circuit/figure
number Quantity Part number Description
-- -- -- 1EA 075-0301-02 INSTRUCTION,KIT; ACQUISITION BOARD RE-
PLACEMENT, 050-3302-XX VM700A/T
-- -- -- 1 E A 337-4169-xx SHLD GSKT:ELE FINGER CLIP-ON,0.5L X
0.38W,BECU;VM700A
-- -- -- 1 E A 407-4585-xx BRACKET:EMI,0.062 THK,RIGHT SIDE
FRT,ETCH&CLEAR CHROMATE;VM700T
A18 1EA 671-4108-xx CIRCUIT BD ASSY:ACQUISITION

Kit Description
4Acquisition Board Replacement

Acquisition Board Replacement 5
Installation Instructions
These instructions are for personnel familiar with servicing. If you need further
details for disassembling or reassembling the measurement set, refer to the
product service manual. For further assistance call your nearest Tektronix, Inc.,
Service Center or Tektronix Factory Service.
CAUTION. To prevent static discharge damage, service the measurement set only
at an antistatic work station. Observe standard handling precautions for
static-sensitive devices while installing this kit. Always wear a grounded wrist
strap, grounded foot strap, and static resistant apparel while installing this kit.
Install
These installation instructions replace the Acquisition board in VM700T or
VM700A Video Measurement Sets with the VMTB or VMTX Turbo upgrade
installed.
1. Remove the screws at the rear edge of right- and left-side cover panels.
2. Remove both cover panels by sliding them carefully to the rear of the
measurement set and out of the chassis grooves.
3. Set the cover panels aside.
Cover Panel

Installation Instructions
6Acquisition Board Replacement
1. Loosen (but do not remove) two screws on the front of the circuit board
retainer plate as shown in Figure 1.
2. Remove the circuit board retainer plate by sliding it to the left until the screw
heads clear the slots.
3. Set the circuit board retainer plate aside.
Loosen screws (2), slide the
circuit board retainer plate to
the left, then remove.
Right side
Figure 1: Right card cage retainer plate removal
Circuit Board
Retainer Plate

Installation Instructions
Acquisition Board Replacement 7
1. The Acquisition (A18) circuit board occupies the card cage top slot. To
remove this board you must first disconnect four ribbon cables.
Right side
Acquisition board (A18)
Figure 2: Acquisition board Installation
a. Spread the cable ejector tabs to disconnect each cable from the board.
b. Use the ejector tabs to release the circuit board from the interboard
connector.
c. Remove the existing Acquisition (A18) circuit board from the card cage
(see Figure 2).
2. Slide the supplied Acquisition (A18) circuit board in the card cage top slot
and press firmly to seat the interboard connector.
a. Press the four cables into the cable ejector tabs on the acquisition (A18)
board.
Acquisition
Circuit Board

Installation Instructions
8Acquisition Board Replacement
1. Remove the two screws nearest the front of the measurement set as shown in
Figure 3.
Front
EMI
bracket
Slide this end of EMI
bracket in place
Right side
Figure 3: Right side EMI bracket installation
2. Position the bottom edge of the EMI bracket (see right side of Figure 3)
inside the lower lip of the measurement set frame.
3. Align the EMI bracket to the screw holes in the measurement set. Attach and
tighten the two screws as shown in Figure 3.
4. Reinstall the circuit board retainer plate to the right side of the measurement
set as shown in Figure 1.
5. Reinstall the right-side cover panel.
NOTE. If you do not have an I/O CPU (A20) board omit the next procedure.
1. Position the measurement set so that the left side faces you.
2. Remove the circuit board retainer bar from the left side of the measurement
set.
Right-Side
EMI Bracket
Circuit Board
Retainer Bar

Installation Instructions
Acquisition Board Replacement 9
1. Remove the screw holding the CPU I/O (A20) circuit board. The CPU I/O
circuit board (A20) is located in the bottom slot of the card cage.
2. Pull the CPU I/O (A20) circuit board out, just exposing the rear panel
connectors from the card cage.
3. Attach the EMI clip to the rear of the CPU I/O circuit board (A20) as shown
in Figure 4.
CPU I/O (A20 board)
EMI clip
Left side
Circuit board
retainer bar
Figure 4: Location of the EMI clip on the CPU I/O board
4. Push the CPU I/O circuit board (A20) into the card cage. Attach and tighten
the one screw.
5. Replace the vertical bar and screw.
6. Reinstall the left-side cover panel.
EMI Clip for
CPU I/O Board

Installation Instructions
10 Acquisition Board Replacement
Verify the Installation
At power-on, all instrument diagnostics are bypassed for a quicker startup. Run
all the diagnostic tests, including the audio diagnostics, as a verification
procedure. Use the following procedure to force an Auto Reset.
1. Connect the power cord and press on the rear panel power switch (if it is
off).
2. Hold down the Menu button and use the front panel STBY/ON switch to
power on the instrument.
3. After the instrument beeps twice, release the Menu button. The VM700T
displays the VM700T Startup Menu.
4. In the menu, use the control knob to select R ... INSTRUMENT RUN
MODES, and press the Select Line button. A second diagnostic menu is then
displayed.
5. In this menu, select A ... AUTO RESET, and press the Select Line button.
This runs the full set of internal diagnostics. Check that all tests pass as they
run.
If a diagnostics failure is indicated, turn off the VM700T and disconnect the
power cord. Verify that all the circuit boards are properly seated and that the
connectors are installed properly. If a fault is still indicated when you run the
diagnostics again, contact Tektronix Factory Service.
After the diagnostics complete, the upgraded VM700T should initialize in the
Waveform mode.
All Options. All the option diagnostic tests should pass when the measurement set
is powered on. In the event that a diagnostics failure is indicated, turn off the
VM700T and disconnect the power cord. Verify that all the circuit boards are
properly seated and that the connectors are installed properly. If a fault is still
indicated when you run the diagnostics again, contact Tektronix Factory Service.
gEnd of document g
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