Download HA325 Eval guide (generic)

HA325 Horizontal
Output and Flyback Analyzer
Evaluation Guide
Prepared For:
Your Sencore Contact:
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Getting Started
This Evaluation Guide will help you understand the
basic operation of the HA325 and show you how to
analyze horizontal output stages faster and more
efficiently. It includes simplified hookup, step-bystep instructions and a checklist to familiarize you
with each of the HA325's main test functions.
Follow these initial steps when performing all of
the tests and activities in this guide:
Here’s what you need to get started:
2. Follow the activities for
instructions on where to connect
the test leads to the chassis.
1. Disconnect AC power from the
video display chassis. All HA325
tests are performed with no AC
power applied to the chassis.
 A working CRT-based video display. Your success
in servicing horizontal output stages with the
HA325 depends on understanding how a working
monitor responds to the tests.
Caution
The HA325 Load Tests produce current and
inductive voltage pulses in the chassis horizontal
output stage. Be careful not to come into contact
with these energized circuit points while performing
the tests. Connect or disconnect the test clips with
the HA325 powered off, or with the HA325 in the
SETUP OPTIONS display.
 Use a display that you have a schematic for. This
eliminates uncertainty in locating test points and
interpreting test results while you are learning
how to use the HA325.
 HA325 Horizontal Output & Flyback Analyzer.
The HA325 is shipped without the battery
charged. To use the HA325 you will need to power
it with the AC Power Adapter/Charger. For
battery operation allow the internal battery to
initially charge for 24 hours.
3. Turn the HA325 On and Off by pressing the
POWER ON/OFF button located in the lower
left corner of the unit.
 Optional: Piece of solder, short jumper lead, outof-circuit IHVT or flyback. These items will allow
you to perform the optional activities.
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Controls
LOAD TEST – HORIZ.
OUTPUT: Selects Horizontal
Output Load Test and
initiates the setup process.
TEST/SETUP: Switches
display between SETUP or
LOAD TEST display window
during Load Test functions.
LOAD TEST – FLYBACK &
IHVT: Selects Flyback &
IHVT Load Test and initiates
the setup process.
ENTER: Use with the UP &
DOWN ARROWs to enter
the selection.
UP and DOWN Arrows: Use
to move the display cursor up
or down to select from the
displayed options.
RINGER TESTS: Press
button corresponding to
component type to Ringer
test.
Power: Momentarily press to
turn HA325 on or off.
ASSISTANCE: Provides
assistance messages to guide
you to the defective
component or test.
Why Does It Beep?
If you leave the HA325 turned on without pressing
any buttons you soon will hear it “beep”. These
beeps come from the HA325’s Power management.
The HA325 has 3 levels of power management. The
first level disables the display back light if no
button has been pushed for 60 seconds. The second
level, Standby, is initiated if no button has been
pressed for 5 minutes. Standby is preceded by
audio tones at 2 minutes remaining, 1 minute
remaining and Standby start. The final level of
power management is power shutdown, which occurs
approximately 5 minutes after Standby if still no
buttons have been pressed. Audio beeps are
produced every minute during Standby.
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When to Use the Tests
The HA325 provides three tests that isolate
defects in horizontal output stages and components.
Each test analyzes specific sections of the output
stage or components. Follow the Assistance
messages to know when to use each test. If you are
analyzing an unknown output stage, start with the
Horizontal Output Load Test. Following is a brief
overview of each test.
1) Horizontal Output Load Test
2) Flyback & IHVT Load Test
3) Ringer Test
Assistance Messages
that you check specific components for defects.
The HA325 contains a library of over 60 help
messages to assist you with analyzing horizontal
output stages. These messages will guide you in
setting-up and performing the tests, and will tell
you what the test results mean and what to do next.
Depending on the test result, the help displays may
suggest that you perform another test or suggest
Press the front panel ASSISTANCE pushbutton at
anytime to access the assistance messages. The
messages are always keyed to the current window,
setup, or displayed test results . Releasing the
ASSISTANCE pushbutton resumes the normal
testing or setup function.
The Assistance messages guide
you to the tests to perform and
components to check.
Horizontal Output Load Test
This is the first test to use when analyzing a
suspect horizontal output stage. It determines if
the horizontal output stage is free of severe
defects.
Use when:
What it tells you:
Full AC Power c an't be a pplied due to:
 No/low chassis B+
 Output Transistor shorted or heats
 B+ supply squeals, burns components,
blows fuses
 Shutdown: – Over current or X-ray




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If Horizontal output stage is functional
Short/load on B+ supply
Output stage timing
Output stage efficiency
Flyback & IHVT Load Test
Use this test to isolate the problem when the
Horizontal Output test indicates a defect. This test
analyzes flybacks and IHVTs for internal defects
including shorts or leakage between windings, and
integrated multiplier problems.
Use when:
What it tells you:
Horiz. Output Load Test indicates defect:
 High mA reading
 Low % efficiency reading
High voltage, focus, screen, or secondary
voltages low or missing




Does flyback/IHVT function
Flyback/IHVT mA & efficiency
Isolate AC load to primary or secondary
Flyback/IHVT secondary defect
Ringer Tests
The ringer test confirms if flybacks, yokes,
switching transformers or other coils are free from
shorted turns.
Use when:
Output Load Test indicates a d efect and
suspect defective flyback, yoke or coil
What it tells you:
 Confirm yoke, coil or transformer winding
has a shorted turn before replacing
5
Horizontal Output Load Test
The HA325's Horizontal Output Load test
analyzes horizontal output stages to determine
if they are free of severe defects. The test
simulates normal output stage operation, without
chassis AC power applied, using reduced B+
voltage and current limiting for safe testing.
B+ Input from
power supply
Horizontal output transistor
I. Connect to the chassis
The LOAD/RINGER TEST LEAD clips are colorcoded and labeled to indicate where they
connect to the chassis horizontal output stage.
First, become familiar with the circuit points to
where the HA325 connects. Using the schematic
for your example chassis, locate the following
points
Outpu t stage
ground
 Horizontal output transistor
 Output stage ground
 B+ input to output stage from power supply
____
 when completed
Now connect the HA325 to these chassis points:
1. Connect the black test clip to ground at the emitter or source lead of the output transistor.
2. Connect the orange test clip to the B+ voltage input of the output stage (the B+ side of the transformer
primary or coil winding).
3. Connect the yellow test clip to the collector
or drain of the horizontal output transistor.
The Load Test can be performed with the
chassis output transistor in or out of circuit.
If the Load Test Setup displays “DC SHORT”
or “DC LOAD” remove the transistor from the
chassis, as it is likely shorted.
4. Suggestions on what to do or check next are
always available. To receive a suggestion, press
and hold the ASSISTANCE button.
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II. Select the Output Load Test Setup
1/10th of the normal chassis B+ DCV. The Load Test
Setup display has 8 preset setups, plus AUTO and
Manual. Choose the setup that most closely
matches the display that you are testing, or select
AUTO to let the HA325 decide.
The Load Test Setup determines the frequency and
DC voltage applied to the output stage during the
Output Load Test to produce a flyback pulse test
amplitude between 90-110 VPP. This pulse amplitude
normally occurs at a test frequency near the
monitor's highest operating frequency and at about
1. Press the HORIZ. OUTPUT Load Tests button. This will
display the Setup options window.
2. Push the UP and DOWN ARROW buttons to position the
desired selection beside the cursor.
3. Press and hold the ASSISTANCE button. The message will
direct you to the correct setup.
4. Press the ENTER button. The display will
automatically switch to the Test display window.
____
 when setup is completed
III. Perform the Output Load test
During the Horizontal Output Load test the
current, efficiency and timing parameters in the
output stage are monitored and displayed . These
1. The Output Load test begins and the display
changes to TEST HORIZ. OUTPUT as soon as
you select a setup option by pressing ENTER.
2. Record the test results for a good output stage.
__________ mA
__________ uS
_________ % Eff
3. Press and hold the ASSISTANCE button. The
message should show “Good Horiz. Output No
Load or Timing Defect”.
parameters are used by the HA325 to determine if
the output stage is good or defective, and to display
the proper guidance when you press the
ASSISTANCE button.
Current
Efficiency
Pulse Duration
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Simulating A Bad Output Stage
The Load Test interprets the test parameters and
displays a "Good", "?" or "Bad" indication for each.
These indications are based upon the type of output
stage selected during Setup. Much more
information on what to check for or do next is
available by pressing the ASSISTANCE button.
To see the value of the assistance displays, let’s
simulate a common output stage problem – an AC
load - by wrapping a piece of solder around the
flyback core. (A short piece of insulated wire will
also work, as long as the ends are bare and make an
electrical connection when wrapped together).
1. With the Horiz. Output Load test running, wrap a piece
of solder around the flyback/IHVT core and twist the
ends together to form a shorted loop.
(You should see a large current increase and much lower
% Eff. If not, check that the solder is looped around the
core and with the ends twisted together).
2. The display now indicates an AC Load problem. Read
and record the Load test parameters for this defective
output stage.
_____________ mA
_____________ uS
____________ % Eff
3. Press and hold the ASSISTANCE button. What message is displayed?
The assistance message tells you that the HA325
detects a bad output stage and suggests additional
checks and tests to narrow down the cause of the
defect. In this example, you are prompted to do the
following: (your assistance message may differ
somewhat depending on display type and setup)
 Check the connections & test Setup (you want to
make sure that you’re not troubleshooting a
problem that doesn’t exist)
 Load Test the IHVT (this will help narrow down
the defective component)
!
The Assistance messages are based on the measured
parameters and provide suggestions that guide you to
the defective component.
____
 when simulated bad stage is completed, be sure to remove the solder short.
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IHVT/Flyback Load Test
Use the FLYBACK & IHVT Load Test as directed by
the assistance messages whenever the Horiz.
Output Load Test indicates an output stage loading
problem. This test will isolate loading defects to
either the output stage’s primary circuit
components or to the flyback/IHVT and secondary
circuits. Good Flyback/IHVT Load Test readings
indicate there are no problems with the flyback or
secondary loads.
I. Isolate The Primary From The Circuit
To perform the FLYBACK & IHVT Load Test you must
partially disconnect the flyback/from the circuit to
isolate the primary winding from the output stage. Do
this by unsoldering or opening the connection to the
primary pin of the flyback that leads to the
collector/drain of the output transistor and other
primary components. Be sure to open any other primary
winding pins that contain timing capacitors or primary
components.
____
 when primary winding is isolated
II. Connect to the chassis
1. Connect the black test clip to a ground pin of
the flyback/IHVT.
2. Connect the orange test clip to the B+ voltage
input to the transformer primary winding.
3. Connect the yellow test clip to the flyback
primary winding pin that was disconnected
from the collector/drain of the output
transistor.
____
 when all connections are made
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Open connection to
isolate primary
winding
III. Select the Load Test Setup
The IHVT/Flyback Load Test Setup display has 2
preset setups plus AUTO and Manual. Use “AUTO”
to let the HA325 find the setup. Use “TV” to test
television flybacks/IHVTs, and “HI-SCAN” for
HDTVs, multi-media, computer monitor and highresolution displays. Use “MANUAL” if you need to
1.
change the test frequency or DC voltage to obtain
normal test pulse amplitudes between 80-110 VPP.
Press the Flyback & IHVT Load Tests button.
2. Push the UP and DOWN ARROW buttons to position the
cursor beside the desired selection.
3. Press and hold the ASSISTANCE button. The
message will direct you to the correct setup to use.
4. Press the ENTER button. The display will
automatically switch to the Test display window.
____
 when setup is completed
IV. Perform the Flyback/IHVT Load test
Flyback current draw, efficiency, and timing parameters are
monitored and displayed during the test. These are used to
determine if the flyback/IHVT and secondary loads are good
or defective, and to provide the proper ASSISTANCE help
display.
1. The Flyback/IHVT Load test begins as soon as you select
a setup option by pressing ENTER.
2. Read and record the test parameters for a good IHVT
and secondary loads.
____________ mA
____________ uS
___________ % Eff
3. Press and hold the ASSISTANCE button. The message should indicate a good flyback or IHVT. If the
load test failed, you would be prompted for what to check next.
____
 when completed
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Simulating A Bad Secondary Load
When the Flyback/IHVT Load Test detects a defect
suggestions for what to check next are available by
pressing the ASSISTANCE button. We’ll simulate a
secondary load to see some of these displays.
1. Disconnect the orange test clip to stop the test.
(Remember – large, induced voltages and currents may
be present during the Load Tests)
2. Using a jumper lead, short one of the secondary pins of
the flyback/IHVT to ground.
3. Reconnect the orange test clip to start the test.
4. Read and record the Load test parameters with a shorted secondary load.
___________ mA
___________ uS
__________ % Eff
5. Press and hold the ASSISTANCE button. What
message is displayed?
!
The Assistance display suggests the flyback/IHVT
may be defective and recommends that you open the
secondary loads. Open the secondary circuit paths one
at a time, and repeat the Flyback & IHVT load test while
noting the readings. If the readings drop to “good“ that
load circuit is defective.
____
 when completed
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Ringer Test
The Ringer Tests locates shorted turns in yokes,
flybacks, coils, and switching transformers that
cannot be detected with other tests. Use the
Ringer Test to confirm a suspect component before
replacing it. The test places a capacitor in parallel
with the coil and pulses the cap/coil combination.
The display shows how many times the coil oscillates
or “rings” before dampening. Readings “10” or higher
mean the coil does not have a shorted turn. (“10” is
only a good/bad reference point – a coil that rings
35 is not better than one that rings 20).
I. Isolate The Component
Low impedance circuit paths may cause a good winding to ring less
than ten. To insure that circuit loading does not affect the Ringer
test result follow these guidelines:
 Coils: Disconnect one lead from the circuit
 Flybacks, IHVTs, Switching transformers: Disconnect one

side of the primary winding.
Flybacks, IHVTs: Disconnect the yoke and CRT socket.
If the transformer rings less than 10, continue disconnecting the
remaining windings until the component either rings >10 or is
completely disconnected from the chassis.
II. Connect To The Component
Connect the orange and black test clips to the
primary winding of a flyback/IHVT or
switching transformer. You only need to ring
the primary winding because a shorted turn
causes all other windings that share the
common core to ring bad.
III. Perform the Ringer Test
1. Push & release the appropriate RINGER TEST button.
2. Read the ring count result in the display.
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Isolate primary
winding or coil
A note from...
T
hank you for taking time to evaluate the HA325 Horizontal Output & Flyback
Analyzer. I think you’ll agree that troubleshooting horizontal output stage problems is
some of your most difficult service work with all of the high current, circuit interaction,
and potential for component damage involved. Today’s high resolution, big-screen displays
only compound the problem. Greater deflection and beam currents add more stress to
already hard-working circuits. Plus, it’s no fun hauling a big-screen back and forth to the
shop and then having to re-converge it when you get it up and running. That’s why I’m so
pleased to be able offer you this hand-held analyzing solution.
Let me recap just a few ways how the HA325 will make money for you:







Cash-in on the servicing opportunities offered by big tube direct-view, projection and
HDTVs in Home Theater and all sorts of commercial installations. (If you don’t,
someone else will.)
Eliminate the liability, expense, and hassle of transporting a chassis to the shop and
back to its installation.
Save time on each repair and fix more displays in the same time.
Eliminate frustrating guesswork. (I hate frustration!)
Reduced parts costs with fewer destroyed replacement parts and no parts swapping.
Increased repair quality.
On-site/in-home repair for less down-time and increased customer satisfaction.
Which of the HA325 features did you like best? My personal favorite is the Assistance
button. I’m just a mediocre tech, but with the suggestions that those help messages offer
I feel that I’m ready for almost any horizontal output stage problem that comes my way!
I’ll give you a call in a few days so that we can talk about the evaluation and you can tell me
what you liked best about the HA325. If you need to give me a call before then (with
questions about the HA325’s, or to place an order!) give me a call at 1-800-SENCORE
extension
, or email me at
.
Thanks,
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