B+K precision 467 User manual

INSTRUCTION MANUAL
FOR
MODEL 467
CATHODE RAY TUBE
RESTORER/ANALYZER
DIVISION OF DYNASCAN CORPORATION
1801 West Belle Plaine Avenue
Chicago, Illinois 60613
INSTRUCTION
MANUAL
S>K PRECISION

INTRODUCTION
TABLE OF CONTENTS
ri
Page .
INTRODUCTION AND SPECIAL FEATURES. 3
SPECIFICATIONS . 4
SAFETY PRECAUTIONS . 5
BRIEF SUMMARY OF WHAT THE 467 WILL DO. 5
CONTROLS AND INDICATORS. 6
USING THE MODEL 467 .. 9
Operation . 9
Restoring the Picture Tube . 13
Cleaning, Balancing and Rejuvenating. 14
HOW THE MODEL 467 WORKS . ... 16
Emission Test .. 16
Tracking Test. 16
Leakage Test. 16
life Test. 20
Focus Test . 20
Shorts Removal. 22
Cathode Restoring . 23
SERVICING . 26
Field Calibration. 26
SET-UP CHARTS. 27
WARRANTY INSTRUCTIONS.. . 28
WARRANTY. 28
THE MODEL 467 USES UNIQUE TRIDYNAMIC® APPROACH
The Model 467 CRT Restorer/Analyzer has been designed by B & K-Precision to evaluate
most television picture tubes, computer terminal displays, or other cathode ray tubes
with a high degree of accuracy. This professional quality CRT tester utilizes solid state
digital muliplexing circuits which provide new testing capabilities. This unique
TriDynamic® approach to CRT testing makes it possible to test all types of CRT’s —
even Trinitrons and in-line types — by using just one simple test procedure.
SPECIAL FEATURES
Each test function has been designed to provide more rapid testing, in addition to
reducing human error. These features include;
1. A control panel which guides the user easily through the correct test sequence.
2. Three precision meters that display emission from all 3 guns simultaneously, to
minimize testing time.
3. Simultaneous leakage measurements between all important elements. No
controls to adjust. Even cathode-to-cathode leakage can be detected.
4. Heater voltage, G1 voltage, and line voltage are precisely and simultaneously
indicated on the three meters.
5. Continuously variable heater voltage, which can be precisely set on the meter.
All common CRT heater voltages are premarked on the meter scale. The
voltages to G1 and G2 are continuously variable, permitting the tube to be
checked under conditions simulating its actual use in the receiver.
6. New color tracking feature which greatly reduces time required for determining
proper color gun tracking.
7. A new, greatly improved rejuvenation capability is provided for each gun
independently. The entire process is automatically timed and operated by
simply depressing the RESTORE button. The rejuvenate feature provides
maximum cathode restoration while at the same time minimizing the
possibility of cathode destruction.
8. Simplified automatic life test.
9. Function switching between rejuvenation and emission test permits instant
evaluation of restoration effectiveness.
10. New, improved, more versatile adapter set is included. It provides capability to
directly test more CRT types with fewer adapters than any other currently
available tester.
11. Continuity to focus electrodes is quickly checked by the simple push of a
button.
12. Short indicator lamp shows instantly when Gl-K short has been successfully
removed.
3

SPECIFICATIONS
TYPES OF CRT’S TESTED: Most black and white and color TV picture tubes,
video monitors, and computer terminal CRT’s*
TESTS PERFORMED:
Emission
Leakage
Tracking (Color Tubes)
Life
Focus Continuity
RESTORING FUNCTIONS:
Shorts Removal
Gun Cleaning and Balancing
Cathode Rejuvenation
METERS: (Three; 2W’; D’Arsonval movement*)
Meter Indications:
Emission (0-2mA)
Restoring Current (0-2 scale)
Heater Voltage (0-15V)
G1 Bias Voltage (30-100V)
Power Line Voltage (100-130V)
TEST VOLTAGES:
Heater: 0 - 7 @ 2.0A
7- 14 @ 600 mA
G1 Bias: Neg. 30 to Neg. 100 VDC
G2 Supply: Normal, 0-350 VDC
High, 180-530 VDC
ACCESSORIES:
CRT Socket Adapters: 6 supplied; optional adapters available for all common
TV picture tubes.
Set-up Chart: Shows adapter number and test voltages*
POWER REQUIREMENTS: 117 VAC, 60 Hz, 40 Watts,
FUSES (INTERNAL): Heater Supply - Type 3AG, 0.3A Slo-Blo
High Voltage Supply — Type 3AG, 3/8A Slo-Blo
CASE: One-piece, high-impact polyethylene, with internal cord and adapter
storage,
SIZE: 13W” x 10” x 5%”.
WEIGHT: 10 lbs.
4
SAFETY PRECAUTIONS
1. The proper power line supply voltage is indicated on the chassis where the power
cord enters the instrument. Do not attempt to operate this instrument from a power
source other than specified.
2. When testing any CRT that is installed in a chassis, first disconnect the chassis
power plug from the AC line outlet . Do not apply power to the TV chassis at any
time during the test of a CRT.
3. Read and observe the “Test Instrument Safety” recommendations on the inside
front cover of this manual.
BRIEF SUMMARY OF WHAT THE 467 WILL DO
The Model 467 CRT Restorer/Analyzer will:
1. Rapidly test a cathode ray tube for satisfactory emission.
2. Restore tubes having low emission.
3. Check for shorts or leakage between the elements in the tube, and also indicate
between which elements the fault exists.
4. Check relative cathode emission, to directly and rapidly indicate balance
(tracking) between the guns of a color CRT.
5. Check the life expectancy of the tube.
6. Repair the most common shorts in cathode ray tubes: those between cathode
and Gl.
7. Check continuity to the focus electrode of the gun(s).
5

CONTROLS AND INDICATORS
1. Function Switch:
2. G2 Voltage Range Switch:
NORMAL position
HIGH position
3. HTR RANGE Switch:
0 — 4 position
4 — 7 position
7 - 9 position
8-11 position
10-12 position
12 - 14 position
4. SET HEATER Control:
5. RED/B&W meter:
6. SET G1 Control:
7. GREEN Meter:
8. BLUE Meter:
Selects Main Functions.
POWER OFF
SET-UP
SET CUTOFF
TEST EMISSION
RESTORE
Selects two ranges of G2 supply
voltage.
0- 350 VDC
180- 530 VDC
Coarse adjustment of heater voltage.
0-4 VAC @ 2.0A
4- 7 VAC @ 2.0A
7- 9 VAC @ 0.6A
8- 1 1 VAC @ 0.6A
10- 12 VAC @ 0.6A
12- 14 VAC @ 0.6A
Fine adjustment of heater voltage
±2 VAC.
Reads emission of red gun or black
and white tube. Reads heater volt¬
age when FUNCTION SWITCH (1)
is in SET-UP position.
Adjusts control grid bias voltage
when FUNCTION SWITCH (1) is in
SET-UP position.
Reads emission of green gun. Reads
value of Gl bias voltage when
function switch is in SET-UP
position.
Reads emission of blue gun. Reads
power line voltage when FUNC¬
TION SWITCH (1) is in SET-UP
position.
6
9. LEAKAGE Lamps:
10. G2 Control - RED
11. G2 Control - GREEN
12. G2 Control — BLUE
13. TRACKING Pushbutton:
TRACKING Control:
14. LIFE Test Pushbutton:
15. FOCUS Test Pushbutton:
FOCUS OK Lamp:
16. REMOVE SHORTS Pushbutton:
Gl-K SHORTS Lamp:
17. REJUVENATE/CLEAN*BALANCE
Selector Switch:
18.
19. RESTORE Pushbuttons:
20 .
21. RESTORE Ballast Lamp:
22. POWER Lamp:
Indicates leakage from cathodes to
heater or Gl and between cathodes
when FUNCTION SWITCH (1) is in
SET-UP position.
Adjusts value of G2 voltage to SET
CUTOFF condition of test.
Activates tracking adjustment con¬
trol.
Simultaneously varies readings of
the three emission meters (5, 7, 8,)
from 10% to 90%.
Automatically reduces heater volt¬
age by 15% from the value set on
meter (5) •
Activates focus electrode continu¬
ity test.
Indicates continuity from CRT base
pin to focus electrode.
Discharges capacitor through short
between Gl and cathode.
Indicates presence of short circuit
between Gl and cathode.
Selects value of high voltage to be
used for REJUVENATE or
CLEAN^BALANCE operation.
Applies restoring voltage between
Gl and cathode, and simul¬
taneously interrupts heater voltage.
Indicates restoring current in ballast
lamps.
Indicates power is “on”.
7

USING THE MODEL 467
8
I
INTRODUCTION \
The following procedure describes in detail the use of the 467. In addition,
comments and notes are provided regarding the significance of the readings to aid
the user in interpreting the measurements obtained.
Because of the unique design of this instrument, all tube types are tested in the
same manner regardless of gun structures. After the user has become thorpughly
familiar with the instructions and the instrument itself, he will need only to refer to
the SET-UP CHART booklet.
HOW TO USE THE SET-UP CHARTS
For convenience, color and black/white CRT’s are grouped separately. In each
group the tubes are listed first in increasing numerical order by screen size, whether
in inches or millimeters; then in alphabetical order, by the letters following the
screen size.
Foreign tubes having alphabetical prefixes are listed at the end of the listing of
tube types having numerical prefix identification.
OPERATION
(Refer to Control Panel Illustration)
A. SET-UP:
1. S et FUNCTION Switch (1) to the OFF position.
2. Plug the Model 467 line cord into a convenient power outlet.
3. Set all variable controls fully counterclockwise.
4. Locate the type number of the CRT to be tested in the SET-UP CHART.
5. Select the adapter by the number indicated and connect it to the adapter
cable.
6. Place the G2 NORM/HIGH (2) in the NORM position.
7. Set the HTR RANGE Switch (3) to the range which includes the heater
voltage shown in the SET-UP CHART.
8. If the CRT to be tested is mounted in the TV set, make sure that power to
the TV set is removed, preferably by unplugging the set. A shock hazard
and possibility of damage to the 467 exists if an attempt is made to test
the CRT with the TV set operating.
9. Connect the socket adapter to the base of the CRT, taking care to align
keyway properly.
10. R otate the function switch to SET-UP position.
9

11. Carefully adjust the SET HTR control (4) while observing the HTR
•VOLTS scale of the RED/B&W meter (5) for the heater voltage indicated
in the SET-UP CHART. For convenience, the most common heater
voltages are precisely marked.
12. Adjust the SET G1 control (6) while observing the G1 VOLTS scale of the
GREEN meter (7) until the meter indicates the value of G1 specified in
the SET-UP CHART. (50V unless indicated by*.)
13. The LINE VOLTS scale on the BLUE meter (8) automatically monitors
line voltage present at the time of the test while the FUNCTION switch is
in the SET-UP position. This may be helpful in diagnosing some symptoms
related to low line voltage. For example, a marginal picture tube might
perform very poorly with low line voltage because of the reduced heater
voltage.
B. L EAKAGE TEST:
With the FUNCTION switch in the SET-UP position, observe the five
LEAKAGE lamps (9). When glowing, these lamps automatically indicate
leakages between cathodes, or from any cathode to the heater or to Gl. For
example, if the KB, KR, and Gl lamps glow, it is an indication of leakage
between the blue cathode, the red cathode, and the control grid. Only those
elements which have leakage between them, in the order of 2 megohms or less,
will be indicated by the lamps glowing.
NOTE
If the leakage lamps glow very faintly, even though the CRT tests
normal in all other functions, the cause may be dirt or other
contamination between the tube base pins. This can usually be
ignored.
Heater-Cathode Leakage: Leakage between heater and cathode cannot be
repaired. When such leakage is determined to be the cause of set malfunction,
it is necessary to replace the picture tube. If the TV heater power source
permits the use of an isolating transformer, its use mfay restore normal
operation.
Cathode-to-Cathode Leakage: Excessive leakage between cathodes can some¬
times result in TV set malfunction. Such leakage cannot be repaired.
Grid-to-Cathode Leakage: Excessive leakage or a short between the control
grid and cathode is a common fault in picture tubes. Any current path below
two megohms will light the Gl-K LEAKAGE lamp (16). Shorts and leakage
paths below 20k ohms will also light the Gl-K SHORTS lamp when the
function switch is in the RESTORE position. If only leakage is indicated,
restore the tube by using the CLEAN»BALANCE procedure; if a Gl-K short
exists, use the REMOVE-SHORTS procedure (see “RESTORING THE
PICTURE TUBE”).
10
C. S E T CUT-OFF:
1. Rotate the FUNCTION Switch to the SET CUT-OFF position. The 3
meters should read zero or slightly above or below zero.
2. Slowly advance each of the three G2 controls (10), (11), and (12)
clockwise until the corresponding meter rises one small division of the
meter scale. This adjustment sets the G2 voltage at the value for spot
cut-off of each color gun. If a tube or gun cannot be brought out of
cut-off by advancing the G2 control fully clockwise, place the G2
NORM/HIGH switch (2) in the HIGH position.
NOTE
For black and white tubes, use only the RED G2 control. Make sure
the others are turned fully counterclockwise.
D. EMISSION TEST:
Rotate the FUNCTION Switch to the TEST position. The three meters will
indicate the cathode emission current for each of the three electron guns. In
some instances, the meters may read somewhat beyond the full scale
deflection. This indicates that the tube has excellent emission. A greater than
full scale reading will not in any way damage the instrument. In some cases, the
current may rise to approximately Vi or % scale and then slowly decrease.
Evaluation of emission should be made when the readings have stabilized. In all
cases, if the emission readings stay well within the green (GOOD) area, the
emission characteristics of the tube may be considered acceptable. If emission
reads in the red (BAD) area, proceed to REJUVENATE (see “RESTORING
THE PICTURE TUBE”).
E. TRACKING TEST:
1. With the FUNCTION Switch in the TEST position, depress and hold the
TRACKING pushbutton (13),
2. With TRACKING button depressed, rotate the TRACKING knob (13) so
that the pointer of the highest reading meter coincides with the SET
TRACKING LINE located at the high end of the yellow wedge on the
meter scale.
3. Observe the other two meters and note if the readings are within the
yellow tracking wedges on each meter. If all three pointers are within the
yellow wedges, the tracking ratio of the CRT is acceptable. If the tube
does not track, proceed to CLEAN®BALANCE (see “RESTORING THE
PICTURE TUBE”).
4. When the TRACKING button is released, the three meters immediately
will return to the original emission readings that were obtained in the
emission test. The tracking pushbutton may be depressed as often as
desired without affecting the calibration of the emission readings.

F. LIFE TEST:
1. With the FUNCTION Switch in the TEST position, depress and hold the
LIFE pushbutton (14) and allow the emission readings to stabilize. For
acceptable long term CRT performance, the readings should stay in the
green (GOOD) area. The less the emission drops, the longer the life
expectance of the tube.
2. While holding down the LIFE button, depress the TRACKING button and
perform the TRACKING test of Step E. For acceptable long-term
performance, the CRT should maintain tracking with the LIFE test button
held down.
3. Release the LIFE and TRACKING buttons.
4. If life expectancy is poor, proceed to CLEAN«BALANCE.
NOTES
Other clues for judging life expectancy are obtained by observing the
“warm-up” and “cool-off’ behavior of the cathode. To make these
observations in the TEST position, press any RESTORE pushbutton
(18, 19, 20). This interrupts the heater circuit and makes it possible
to observe the rate at which the emission rises and falls as the
cathode heats up and cools down.
Since the emission from all three guns of a color CRT is displayed
simultaneously, significant differences between cathodes are easily
observable. If, for instance, during warm-up, one gun reaches full
emission much slower than the other two, it is an indication that
there may be very little good material left on that cathode or that its
heater has been dislodged away from the cathode causing lower than
normal cathode temperature. In either instance, it is a further
indication that short life may be expected from that gun. A good
tube will reach full emission levels and will track within two
minutes.
Similarly, the “cool-off’ characteristic can provide another clue for
judging life expectancy. Observe the time it takes for emission from
each gun to fall after the heater voltage is interrupted. If, for
instance, two guns maintain full emission for 7 to 10 seconds, and
the third gun falls rapidly after 3 or 4 seconds, short life can be
expected from that gun.
G. FOCUS ELECTRODE CONTINUITY TEST:
With the FUNCTION Switch in the TEST position, depress the FOCUS
pushbutton (15). Observe the FOCUS-OK lamp (15). If the FOCUS-OK lamp
glows or flickers, the focus electrode continuity to the tube base pin is good.
12
i
i
I
NOTE
It is also possible to check for an open interconnection in color
CRT s, with individual focus electrodes that are internally connected
by welded straps. To do this, push the FOCUS test button and
observe the 3 emission readings on the meters.
If all 3 meter readings drop approximately the same amount, the
inter-electrode continuity is good.
If one or two meter readings drop slightly whil^ the other drops to
near zero, there is no continuity to the focus electrode of the low
reading gun, even though the FOCUS-OK lamp glows.
If the tube tests bad for focus continuity, a decision to replace the tube should
be based on actual performance in the TV set. If the focus is not objectionable
to the customer, the CRT need not be replaced.
RESTORING THE PICTURE TUBE
The Model 467 employs three restoring functions: REMOVE SHORTS,
CLEAN*BALANCE, and REJUVENATE. All three are available in the RESTORE
position of the function switch.
LEAKAGE AND SHORTS: Excessive leakage or a short between the control
grid and cathode will show up in the LEAKAGE test that is automatically
performed during SET-UP. A low resistance short (less than 20k ohms) can be
removed by the REMOVE SHORTS procedure. High resistance leakage is most
successfully removed by the CLEAN*BALANCE procedure. If grid-to-cathode
leakage was indicated in the LEAKAGE test during SET-UP, use the following
procedure.
A. REMOVE SHORTS:
1. Set the FUNCTION SWITCH to the RESTORE position.
2. Observe the Gl-K lamp (16). If it is not glowing, a high resistance leakage
is indicated; use the CLEAN»BALANCE procedure.
3. If the Gl-K lamp glows, push the REMOVE SHORTS button (16) and
release. If the short has been successfully removed, the lamp will not glow.
4. If the lamp continues to glow, repeat Step 3 several times. Wait 5 to 10
seconds between operations. If the short has not been successfully
removed, reduce the heater voltage by turning the HTR RANGE (3)
switch to the lowest range. If the Gl-K shorts lamp goes out as the
cathode cools, it indicates that the short may be due to mechanical
expansion of the cathode. Such shorts usually cannot be removed.
5. After the short is removed, resume the testing procedure.
13

NOTE
One or more LEAKAGE lamps may glow temporarily if the
FUNCTION switch remains in RESTORE position for longer than
15 seconds. Also, if returning to SET-UP to re-check leakage, wait at
least one minute to get a true leakage indication.
CLEANING, BALANCING AND REJUVENATING
Cleaning and balancing is a low energy restoring operation. It can be used
safely on all tubes to eliminate surface contamination causing high resistance
leakage or for further improving the emission of a fairly good cathode to restore
tracking or increase life expectancy. Rejuvenation is a higher energy procedure for
restoring cathodes when the emission is below usable levels.
High level rejuvenation of one gun can occasionally reduce the previous emission
reading of another gun, particularly if that gun had just been rejuvenated.
Therefore, after rejuvenation, it is often desirable to “touch-up” by cleaning and
balancing one or more of the guns in order to achieve good tracking.
B. CLEAN«BALANCE:
1. Set the FUNCTION Switch to the RESTORE position and the REJU-
VENATE/CLEAN.BALANCE Switch (17) to CLEAN*BALANCE. Wait
20 to 30 seconds. Observe the CRT heater for increased brightness from
the higher heater voltage.
2. Push and hold the RESTORE button (18), (19), or (20) for the gun to be
cleaned or balanced. The meter should rise immediately to a value near
midscale. After several seconds or more, depending upon the condition of
the cathode, the pointer will begin to fall. It usually will fall smoothly to
some low value.
3. Release the RESTORE button when the pointer reaches 0.2. If the pointer
drops erratically and then “hangs up” at a reading greater than 0.2, wait
several seconds and then release the RESTORE button. Also, observe the
Gl-K SHORT lamp. If it is glowing, remove the short before proceeding
further.
4. Return the FUNCTION Switch (1) immediately to SET-UP (if LEAKAGE
was being removed), or to TEST (if balancing or “touch up” was being
done). Resume testing.
5. If the CLEAN*BALANCE procedure was not successful and the condition
of the CRT is still unsatisfactory, use the REJUVENATE procedure.
C. REJUVENATE:
1. Set the FUNCTION Switch (1) to the RESTORE position. Set the
REJUVENATE/CLEAN«BALANCE Switch (17) to REJUVENATE. Wait
20 to 30 seconds.
2. Push and hold the RESTORE BUTTON (18), (19), or (20) for the gun to
be rejuvenated. The pointer immediately will rise to about 3 A scale and the
RESTORE ballast (current limiting) lamp (21) will glow brightly. After
several seconds, the pointer will begin to fall. Often the pointer will fall
erratically or hesitate near midscale and then rise slightly before
continuing to fall. This behavior is usually accompanied by observable
sparking and Sputtering action between the grid and cathode.
3. Release the RESTORE button when the pointer reaches 0.4 or just as it
crosses into the red area of the meter. If the emission does not fall to 0.4
after several seconds, release the RESTORE button immediately. Observe
the Gl-K SHORTS lamp (16) to see if a short was created by the
rejuvenation process. If a short exists, use the REMOVE SHORTS
procedure.
4. Return to TEST. Allow time for readings to stabilize. A rapid judgment of
relative improvement can now be made. For greater accuracy, repeat
SET-CUTOFF.
5. Repeat LIFE and TRACKING tests. If slight further improvement is
needed, or if rejuvenation caused lower emission from one of the other
guns, use the CLEAN*BALANCE procedure.
6. If the CLEAN»BALANCE procedure after rejuvenation does not give the
necessary improvement, repeat REJUVENATE. Most cathodes will achieve
90% or more of the possible improvement in a single operation. Some will
require two or three cycles of rejuvenation for maximum improvement.
Further rejuvenation generally causes lower emission and shorter life. The
fewer rejuvenation cycles that are used to achieve satisfactory emission,
the greater will be the life expectancy.
NOTES
If the meter pointer does not rise when the RESTORE button is
pushed, it indicates that successful rejuvenation is probably not pos¬
sible. If the reason for lack of emission is an extremely inactive (con¬
taminated) cathode, it is sometimes possible to start the rejuvena¬
tion process by applying even higher heater voltage than normally
used for rejuvenation. To try this, go back to SET-UP and increase
the heater voltage approximately 25% above the normal setting
(8.0V for 6.3V tubes). Then return to RESTORE and attempt
rejuvenation. Since the tube is not useful anyway, the risk is small.
The greatest danger is that excessive heater voltage will expand the
cathode so far that a short to G1 will be created. Also, of course, the
heater itself could be burned open by the higher voltage, although
this occurs less frequently than a short.
If all three guns show initial low emission (BAD), rejuvenation of
one gun will often result in some improvement of the other two
guns. (This is caused by the elevated heater voltage which is a mild
form of rejuvenation in itself.) These guns should also be reju¬
venated, however, even though the emission may have been
improved enough so they read in the GOOD region.
14
15

HOW THE MODEL 467 WORKS
EMISSION TEST
The multiplex test method (Patent Applied For) employed in the DYNASCAN
Model 467 tests the three guns in a rapid-fire sequence, on a 1/3 duty cycle
time-share basis (Fig. 1). Each gun is pulsed 20 times per second and the peak
current of each gun is continuously indicated on its individual meter. The current
indicated is “true” beam current - that is, only the current passing through the G1
aperture. A GOOD emission indication on the meter, therefore, assures that (given
the high voltage), the gun is capable of producing adequate highlight brightness on
the face of the picture tube.
The G2 voltage is supplied by a digitally programmed regulator so that it can be
automatically adjusted to the G2 cutoff value of each gun, during the gun’s test
interval. This is why the test set-up and procedure is the same for even those tubes
that have a common connection to all three G2 elements.
TRACKING TEST
The multiplex system greatly simplifies the tracking test (Fig. 2). The 1 Vi to 1
limit for emission between the highest and lowest guns is checked by showing this
ratio on the meter scale as a yellow wedge extending upward from the GOOD-BAD
limit line. The TRACKING control changes all three meter readings by the same
percentage so that if all three pointers can be placed in the yellow area, you know
the guns are tracking. Changing the three meter readings by exactly the same
percentage is accomplished electronically by changing the duration of each test
interval exactly the same amount. Thus, if each gun is on for only 1/6 instead of
1/3 of the time, each meter reads 50% of its former value.
LEAKAGE TEST
The multiplex system simplifies the leakage test (Fig. 3). Like the limit used to
make a GOOD-BAD judgement of emission, a leakage limit somewhat higher than
the manufacturer’s limit for a new tube is used - a limit at which you might expect
trouble to begin showing up in a typical TV set. Fortunately, such a leakage limit is
just high enough to cause a neon lamp to glow. By using a group of 5 lamps (one
for each cathode, one for the heater, and one for Gl), and multiplexing the test
circuit, we can observe leakage between any two cathodes or from any cathode to
the heater or Gl. (Both lamps will glow, showing which two elements are involved.)
This test is made automatically with the function switch in the SET-UP position
and requires no operator adjustment. It will detect almost any leakage problems
that do occur, including those troublesome cathode-to-cathode leaks.
Fig.
1.
Emission
test
circuit
(simplified).

C> RED CATHODE
I t
I

LIFE TEST
It can generally be assumed that picture tubes showing high emission levels
(1.0mA and over) will continue to perform acceptably for long periods of time, and
that the performance will not be degraded appreciably by abnormal supply voltage
conditions such as low heater voltage. However, when the picture tube shows
emission levels that are relatively low (below 1mA) even though they may be in the
GOOD region, it is highly desirable to evaluate performance both from the
standpoint of future life expectancy and behavior at reduced heater voltage. This is
particularly true with regard to tracking performance, and has become an
increasingly important test in these energy-crisis times of “brown-outs” with
reduced line voltage levels to homes.
One of the best means of estimating the remaining useful life of a picture tube is
to observe the decrease in emission with reduced heater voltage. If the performance,
(either emission or tracking) becomes unsatisfactory with a 15% reduction in heater
voltage, you can be assured that the future useful life of the tube is rather limited.
To facilitate this analysis in the Model 467, a LIFE test pushbutton is provided
which automatically reduces the heater voltage by 15% from any normal value
previously set on the heater voltage meter. Simply depressing the LIFE test
pushbutton permits very rapid evaluation of both the remaining life expectancy of
a picture tube and its performance at reduced heater voltage.
Other clues for judging life expectancy are the “warm-up” and “cool-off’
behavior of the cathode. These tests are easily performed by applying or removing
heater voltage while observing emission. Therefore, those sections of the RESTORE
pushbutton switches that interrupt the heater supply are arranged to be operative in
the TEST position.
FOCUS TEST
When the FOCUS TEST pushbutton is pressed, a large resistance is connected in
series with the G2 electrodes (Fig. 4). The focus electrode(s) however, are
connected directly to the full G2 supply voltage through a sensitive neon lamp. The
large resistor reduces the G2 electrode voltage thus allowing more current to be
picked up by the focus electrode which is indicated by the neon lamp glow.
There will always be some drop in emission when the focus test button is
pressed. Some gun structures will exhibit a large drop and others only a very small
drop. Those guns showing a large drop have a common focus electrode that is
virtually a one piece mechanical structure so that an open connection to a single
focus electrode is practically impossible. However, some gun structures exhibiting a *
small drop may employ separate focus electrodes which are interconnected by a
welded metal strap, and an open connection may occur to only one or two focus
electrodes. Even if the base pin has continuity to only one focus electrode, the test
will still show FOCUS-OK. However, an open focus interconnection to one gun will
show a large drop in emission instead of a small drop, thus making it possible to
detect the open interconnection.
< CN
e>
w
Q
O
8
83
co
O
20
21
Fig.
4.
Focus
continuity
test
circuit
(simplified).

SHORTS REMOVAL
Picture tube guns are constructed with extremely small spacing between the
cathode rfnd the G1 (control) electrode. This close spacing, together with the
possibility of the cathode coating material becoming loose and bridging the gap
between the cathode and the control grid often results in a fairly low resistance
short between these elements. The presence of such a short will be immediately
detected in going through the normal test sequence with the Model 467, because
the leakage indicator lamps will glow brightly showing which cathode is shorted to
Gl. Upon moving the function switch to the RESTORE position another neon
lamp (Gl-K Short) will glow brightly indicating that a low resistance short does
exist (Fig. 5).
Such a short can usually be eliminated by means of a high energy discharge from
a capacitor. Pressing the REMOVE SHORTS button of the Model 467 places a
capacitor (previously charged to a high voltage) across the short (Fig. 6). When the
short has been successfully burned out, the Gl-K SHORT indicating lamp will not
glow.
51K
Fig. 5. Gl-K short indicator lamp (simplified).
22
Fig. 6. Gl-K short removal circuit (simplified).
CATHODE RESTORING
The most effective technique for cathode rejuvenation involves elevating the
heater voltage and simultaneously applying a high positive voltage between G1 and
cathode, thus causing a much greater than normal cathode current to flow.
Unfortunately, unless this process is very carefully controlled, the cathode can
easily be damaged and instead of improving performance, the emission capability of
the cathode is lowered or destroyed.
This problem is avoided in the Model 467 by pre-heating the cathode, and then
initiating the rejuvenation cycle by means of a pushbutton which applies the high
rejuvenation voltage to the control electrode, and simultaneously removes the
heater voltage (Fig. 7). This permits a high rejuvenation current to begin flowing
immediately as the rejuvenation button is pressed, but permits the current to flow
only as long as the cathode retains sufficient heat to maintain the temperature
required for emission. The rejuvenation cycle is therefore automatically terminated
when the cathode cools below the point at which emission can be sustained. This
time interval will depend upon both the condition of the cathode emitting surface,
and the thermal characteristic of the cathode structure. The larger, more rugged
cathodes will result in a longer rejuvenation cycle and, of course, they are the ones
that need and can withstand the longer time interval with less danger of being
damaged. Therefore, the cathode structure itself serves as the automatic timing
element that adjusts the timing interval according to its own needs. This technique,
which prevents simultaneous application of heater and rejuvenate voltage is an
exclusive (Patent Applied For) feature of the Model 467’s cathode restoring system.
23

The same procedure can be used at different energy levels by changing the value
of the applied voltage. Higher voltage is required for rejuvenation to start the
process when the cathode has become an extremely poor emitter. Lower energy
should be used to ndinimize possible damage to the cathode for cleaning high
resistance contamination between grid and cathode, and increasing the emission of
a good cathode to improve tracking. Therefore, it is desirable to use the lower
0 energy procedure provided in the CLEAN*BALANCE function for those
operations.
Describing the emission test earlier, it was pointed out that the Model 467 tests
m the emission and tracking performance of a picture tube by indicating the true
beam current — that is, only the current passing through the G1 aperture which is
useful for producing light output from the face of the picture tube. This beam
current is derived from a very small area of the cathode located directly beneath the
small aperture hole in the G1 control electrode. Obviously, for the rejuvenation
process to be successful it is from this region that emission must be restored. During
the rejuvenation process a very large current flows from the entire cathode surface
to the highly positive G1 electrode. Although the amount of current flow from the
cathode to G1 is an indicator of the overall condition of the cathode, G1 current
itself is of no use in evaluating the ability of the cathode to supply true beam
current. Therefore, in order to know the quality of the tube after the restoring
process has been completed, it is absolutely necessary to make a true beam current
emission test.
*
24
25

SERVICING
* SET-UP CHARTS
WARNING|
1. The following instructions are for use by qualified personnel only. To avoid electric
shock, do not perform servicing other than contained in the operating instructions
unless you are qualified to do so.
2. High voltage up to 600 volts is present when this unit is operating. Line voltage (120 or
240VAC) is present on some components any time the 467 is connected to an ac power
source, even if turned off. Always observe caution when the chassis is removed from
the housing. Contacting exposed high voltage could result in fatal electric shock.
FIELD CALIBRATION
1. Connect suitable AC voltmeter (±3% or better) to pins 1 and 14 of Adapter
No. 3. Connect Adapter to test cord.
2. Set AC voltmeter range switch to 10V.
3. Plug in 467 and set function switch to SET-UP.
4. Set HTR Range switch to 4 — 7 volts.
5. Adjust SET HTR control to read exactly 6.3V on external voltmeter.
6. Adjust R16 (located on printed circuit board) so that HTR volt meter (Red
B&W) indicates exactly 6.3V.
An up-to-date test chart is included with your Model 467. In order to keep your
set-up chart up-to-date, it is recommended that you subscribe to the B&K Chart
mailing service. These mailings will occur in May and November of each year and
will include all the tubes presently listed on your chart plus all new types of CRT’s
that have come out since the last mailing.
If you wish to take advantage of this service, remit cash, check, or money order
(no COD’s please) to:
Service Department
B & K-Precision Product Group
DYNASCAN CORPORATION
6460 West Cortland Street
Chicago, Illinois 60635
and you will be placed on the subscription list.

SCHEMATIC
SYMBOL
DESCRIPTION
B & K
PART NO.
MISCELLANEOUS
FI Fuse* 3/IGA, 250V, 3 AG Slo-Blo . 190-004-9-001
F2 Fuse, 3/8A, 250V, 3 AG Slo-Blo . 190-251-3-308
II, 2 Bulb, 230V, 10W . 400-034-9-001
Nl,2,3, )
4,5,6, > Neon Bulb, NE-2 with T Leads. 401-016-9-001
7,8, j
T1 Power Transformer.. 065-098-9-001
T2 Filament Transformer .062-004-9-001
Ml Meter, Heater Volts. 320-059-9-001
M2 Meter, G1 Volts. 320-060-9-001
M3 Meter, Line Volts. 320-058-9-001
Line Cord. 420-001-9-009
VI 12BH7A Tube . 236-120-2-087
Case Assembly .. 523-107-9-001
Knob, Function. 751-005-9-008
Knob,Small. 751-112-9-001
Knob, Heater Range. 751-115-9-001
Knob, Pushbutton, Black. 384-016-9-006
Lens Cap, Red . 750-003-9-001
Lens Cap, Clear . 750-003-9-002
Tube Chart .. 496-050-9-001
Instruction Manual .. 480-156-9-001
Guarantee, CRT, 20 per pad. 4 8 3 -174-9-001
Output Cable Assembly ..
Rubber Foot . 381-002-9-001
Lamp Socket . 752-007-9-001
Vinyl Divider Hap. 758-021-9-001
Hinge Wire (Flap).. 763-027-9-001
Adapter Storage Assembly. 523-103-9-001
NOTE: Standard value resistors and capacitors are not listed. Values may be obtained from
schematic diagram. Minimum charge $2,00 per invoice. Orders will be shipped C.O.D. unless
previous open account arrangements have been made or remittance accompanies order.
Advance remittance must cover postage or express charges. Specify serial number when
ordering replacement parts.
B & K • DYNASCAN CORPORATION * 1801 W. Belle Plaine Ave. . Chicago, Illinois 60613
B & K MODEL 467 PARTS LIST
488 - 1 4 1 - 9 -002
SCHEMATIC b & K
SYMBOL DESCRIPTION PART NO.
ELECTROLYTIC CAPACITORS
Cl, 2, 3 220/if @ 100V DC . .022-109-9-001
Cl 1,12 50/if @ 450V DC .' *...021-056-9-001
C13, 14 lOOOjitf @ 16V DC . 022-084-9-001
C19, 20 10/if @ 250V DC .021-040-9-001
Dl,2,3,
4,5,6,7,
8,9,10,
11,12,13,
14,15,16,
17,18,19,
20
DIODES & TRANSISTORS
Rectifier, 600 PIV @ 1 Amp.
D20,21,22,l
26 27 28 s [ Silicon Diode, 1N4148
29’ * ’ 1
D30 Germanium Diode, 1N67(A) . . .
D31,36,37 Zener Diode, 56V ±10%, 1 Watt
D32 Zener Diode, 24V ±5%, 1 Watt .
D33 Zener Diode, 5.1V ±5%, 1 Watt.
D34,35 Zener Diode, 91V ±10%, 1 Watt
5^6 7 ^’ } Silicon Transistor, 2N5550 .
151-018-9-001
151-038-9-001
150-008-9-001
152-056-9-001
152-014-9-001
152-030-9-001
152-058-9-001
176-033-9-001
Q8,9,10 Silicon Transistor, SPS2306 . 176-023-9-001
IC1 7473 Dual J-K Flip-Flop . 307-010-9-001
IC2 7400 Quad Two Input NAND Gate. 307-015-9-001
RESISTORS & CONTROLS
R7,8,9 2.4ft ±5%, 1/4W, Carbon Resistor. 002-104-8-249
R10,11,12 316ft ±1%, 1/2W, Carbon Resistor.002-017-9-001
R16 10K, ±20%, Linear Trimpot .^008-058-9-001
R19 499K, ±10%, 1/2W, Carbon Film Resistor.?002-032-9-001
R20 340K, ±10%, 1/2W, Carbon Film Resistor. 002-031-9-001
R23 250K, ± 30%, Linear Trimpot . 008-071-9-001
49,50,51 \ 50R ’ ±10% ’ Lineal ’ */2W Carbon Pot. 008-135-9-001
R39 4.7ft, 10%, 1/2W, W.W. Resistor ;. 006-102-9-479
R43 30K, 10W, W.W. Glass Resistor . 003-010-6-303
R67 3ft ±10%, Linear, 12W, W.W. Pot. ..009-029-9-001
SWITCHES
51 5-position Rotary Switch (Function).083-165-9-001
52 6-position Rotary Switch (Htr. Range). 083-091-9-001
S3,4,5,9 4-Station Pushbutton Assembly. 088-020-9-001
S6,7,8 Pushbutton Switch, DPDT Momentary . 088-021-9-001
S10 SPDT Slide Switch. 084-001-9-001
SI 1 DPDT Slide Switch. 084-001-9-003
COMPOSITE
499-069-9-001

PICTORIAL VIEW OF SWITCH WAFERS j
SWITCH 1 1 FRONT
---
liQi®
SWITCH 1 2-4 FRONT
SWITCH 1 5 FRONT
SWITCH 1 6 FRONT
SWITCH Z | FRONT
SWITCH 1 1 HEAR
$ %
SWITCH 1 2-4 REAR
B j>
Ak
©
SWITCH 1 5 REAR
j SWITCH 1 6 REAR
(gfjf©
SWITCH 2 1 REAR
o ALL WAFERS VIEWED FROM KNOB END
o ALL WAFERS SHOWN IN FULL COUNTER-CLOCKWISE POSITION
SWITCH LEGEND (SI)
NOTE:
1 AUL RESISTORS ARE 5%. 1/4 W.UNLESS OTHERWISE SPECIFIED
2 ALL 1% RESISTORS ARE I/2W,UNLESS OTHERWISE SPECIFIED
3 ALL CAPACITORS SHOWN IN MICROFARADS
4 ARROWS ON POT WIPERS INDICATE CLOCKWISE ROTATION.
5 DIODES I THRU 19. AND 38, ARE . I AMF? 600V .
DIODES 20 THRO 29ARE IN4148
TRANSISTORS I THRU 7 ARE 2N5SSO
TRANSISTORS 8 THRU 10 ARE SPS 2306
6 THIS SCHEMATIC SUBJECT TO CHANGE WITHOUT NOTICE,
? AawZ^indcate logic symbols
( f varies with control scttingsi
MU MODEL 467 RESTORER / ANALYZER
CAUTION : THE UNIT
CONTAINS HIGH
VOLTAGE SUPPLIES,
BE CAUTIOUS WHEN
SERVICING.
WAVEFORMS
OUTPUT CABLE
FUNCTION
WIRE
COLOR
PIN NO.
NTR BLK
1
HTR
BRN 2
Gl RED GRY
3
Gl GRN TAN
4
Gl BUJ PUR
5
K RED
| RED
6
K GRN
GRN
T
K BLU
BLU 8
62 RED ORG 9
G2GRN
YEL
10
62 6UJ
PINK
II
G3 / G4 WHT
12
tiff,
^ J'
PROOUCT OF
DYNASCAN 488-141 9-001
ISSUE-ABCDEFGH