Eico 667 User manual

DYNAMIC CONDUCTANCE
TUBE &TRANSISTOR TESTER
f£/CO*
131-01 39th Ave., FlLshirtg, N- Y. 11352
k.

MODEL 667 ADDENDUM -TRANSISTOR
(For Instruction Manual)
An Improved procedure has been developed for transistor testing, which is described in the
following revision of steps 5to 8on page 7of the Instruction Manual. No transistor chart is
provided, as it is not required when using the revised test procedure. With the great number of
transistors now available, atransistor handbook would be needed, in any case, to determine the
type (p-n-p or n-p-n) and basing of all the transistors to be encountered.
Revised Steps 5to 8, Page 7 of the INSTRUCTION MANUAL:
5. Refer to atransistor handbook for the type (p-n-p or n-p-n) and basing of the transistor to be
tested. Note that only signal transistors can be tested with the instrument and the criteria
described below apply only to signal transistors (not power transistors).
*
6. Insert the emitter (E), base (B), and collector (C) lead of the transistor In the corresponding
terminals of the transistor socket located immediately above the TRANSISTOR TEST selector,
7. Turn the TRANSISTOR TEST selector from "TUBE" to position 1(first position away from "TUBE")
on the p-n-p or n-p-n side depending on the type of transistor under test. The indication on
the meter will be proportional to the collector current with emitter grounded and no base
signal. On this test, transistors in good condition should preferably read in the "Ico GOOD"
area between 0and 40 on the 0to 140 meter scale, but are acceptable with readings up to 80
on this scale. Reject transistor that reads above 80 on this test.
8. Turn the TRANSISTOR TEST selector to position 2(second position away from "TUBE"), and
read the DC Beta (ratio of collector current to base current). The minimum acceptable DC
Beta reading depends on the Ico reading obtained in step 7. The higher the Ico reading (up to
the maximum acceptable limit of 80), the higher the minimum acceptable DC Beta reading is,
in direct proportion* Numerically, the minimum acceptable DC Beta reading is slightly more
than 60% of the Ico reading on the 0to 140 meter scale. Examples: If the Ico scale reading
is 80, the minimum acceptable DC Beta reading is 50; if the Ico scale reading is 40, the minimum
acceptable DC Beta reading is 25.
Page 9of the INSTRUCTION MANUAL:
Delete the following material from the text:
"In some cases, the range of Beta given In the chart has been taken directly from the
transistor manufacturer's specification; in other cases Beta has been calculated from the
grounded base Alpha, Alpha ce, according to the relationship:
Alpha ce
Beta ="
1-Alpha ce
1

MODEL 667ADDENDUM (Continued)
Revise the remaining text as follows:
"These simple tests, when related to each other as described In the test procedure, will
determine If the transistor Is good or bad. They do not, of course, duplicate the factory
tests of frequency response. Input resistance, output resistance, collector capacitance,
and other electrical characteristics that are necessary for aspecific grade of transistor,"
Page 12 of the Instruction Manual:
In Figure n) TRANSISTOR TEST 1, add ashunt resistor R5 across meter Ml.
In Figure o) TRANSISTOR TEST 2, add ashunt resistor R6 across meter Ml.
I. E. 1495 EICO Electronic Instrument Co. Inc,, 131-01 39th Ave, ,Flushing, N.Y., 11352

667 TUBE TESTER ^EICQL,<• page l
GENERAL DESCRIPTION
The EICO Model 667 Dynamic Conductance Tube &Transistor Tester is one of the first
thoroughly practical service instruments able to test both tubes and transistors. Among its
advantages are rapid and simple operation, close simulation of actual tube operating conditions,
and unexcelled thoroughness and accuracy of test. The outstanding mechanical design and
layout, coupled with components carefully selected for ruggedness, makes the Model 667 extremely
well-suited for the hard usage of daily service work.
All components of the Model 667 tube tester are assembled to the heavy-gauge aluminum
front panel, which is in turn top-mounted by 14 screws to flanges on all four sides of the steel
case. Adetachable steel cover is mounted to the back of the case with separable hinges so that
the cover may easily be removed for use of the instrument as acounter -top model or replaced
to convert it back to aportable instrument.
There are ten different tube sockets on the panel to accomodate modern receiving and
other tube types (see Types Tested below). In addition, pilot and Christmas tree lamps can be
checked rapidly using the center of the Novar socket. Aspecial transistor socket accomodates
both n-p-n and p-n-p transistors. To protect against damage due to current overload, atype
3AG 1ampere fuse is connected in series with the primary of the power transformer.
SPECIFICATIONS
LINE VOLTAGE &FREQUENCY: 105- 130V, 60 cycles. Note: Do not connect to adc line.
POWER CONSUMPTION: 10 watts with no tube/transistor under test; 50 watts at maximum load.
TYPES TESTED: 5&7pin Nuvistors; Novars; Compactrons; 7,9, &lOpin miniatures; 5, 6&7
pin sub-miniatures (in-line base); 8-pin sub-miniatures (circular base); octal;
loctal. In addition to receiving types, both domestic and foreign, many
small transmitting and special-purpose tubes, voltage regulators, cold
cathode rectifiers, electron-ray indicators, and ballast tubes are tested.
Tests n-p-n and p-n-p transistors. Pilot lamps are tested in center of
Novar socket. Accessory Model CRU adaptor for testing all color and
black and white picture tubes.
TUBE TESTS: a) Direct-reading of inter-element and cathode heater leakage in ohms on a0to
20 megohms scale. DC test voltage always applied in correct polarity to elimi-
nate emission effects from reading, b) Merit test, which is an emission reading
for diodes and rectifiers and adynamic conductance (combined plate conductance,
mutual conductance, and emission) reading for triodes, tetrodes, andpentrodes.
TRANSISTOR TESTS: N-p-n and p-n-p types.
TRANSISTOR TESTS: a) Leakage measurement of collector current with emitter grounded and
no base signal, b) Direct reading of current amplification factor or
Beta (change in collector current caused by change in base current.
ACCURACY OF LINE VOLTAGE INDICATION: ±3%
SIZE: 12" x15" x6"
WEIGHT: 20 lbs.

PAGE 2««««<« ‘
lEICQL, 667 TUBE TESTER
FUNCTIONS OF CONTROLS
Anecessary supplement to the operating instructions is the following description of control
functions. Several controls, for example, have unusual secondary functions which must be
understood in making settings.
FILAMENT SELECTOR —The dial of this control indicates rms a-c volts tapped from the
power transformer and applied to the tube filament at each position. Do not take the setting
for granted; check the roll chart and set it to the value shown for the particular tube type. The
last position, marked "Z", is used when checking cold cathode tubes such astheOZ4 for which
the plate voltage of the Model 667 is insufficient to initiate conduction in the tube. The 117 volts
available from the FILAMENT switch is thrown in series with the plate voltage of 180 volts at
the "Z" position to provide atotal voltage sufficient to initiate tube conduction. A3K resistor,
placed in series with this circuit, provides current limiting to protect the tube after the start
of conduction.
LINE ADJ. —This control is acontinuously variable potentiometer connected across aportion
of the primary winding. It permits adjustment of transformer secondary voltages to the stand-
ard test values despite line voltage and filament load variations. The LINE push-button serves
to insert astandard resistance in the leakage test circuit whichwill result in exactly half-scale
deflection (LINE mark) when the LINE ADJ. control has been set properly in relation to the
actual line voltage and filament load. The actual line voltage may be read off the dial of the
LINE ADJ. control with an accuracy of ±3% when line adjustment is made under no-load condi-
tions (no tube inserted for testing).
GRID control —Acontinuously variable potentiometer which taps the desired grid voltage up
to amaximum of 5, 15, or 45 volts, depending on the setting of the Vlever. Asnap switch,
which takes up the first few divisions on the dial, is actuated in the most counter-clockwise
position and inserts a400S2 current-limiting resistor in series with the plate supply (for high-
current rectifiers). At settings of 7and above, the resistor is shorted.
PLATE control -- Acontinuously variable rheostat in series with the meter which acts as a
"fine" adjustment of meter sensitivity in conjunction with the "coarse" adjustment provided by
the "S" lever switch.
LEVER switches 1through 12 &C-- These are single section six-position switches which con-
nect the similarly numbered tube socket terminals (lever Cis for the cap lead) to the proper
voltage sources for the tube which is to be tested. At the 1position, each switch contacts
ground; at the 2position, each switch contacts the filament voltage; at the 3position, each
switch contacts the screen voltage; at the 4position, each switch contacts plate voltage; in the
5position, each switch contacts grid voltage; in the 6position, each switch furnishes an open
circuit.
LEVER V-This is athree section switch with four positions (1 through 4). 5, 15, 45, 90 and
180 volt taps on a separate secondary winding on the transformer are so connected to these
switch sections as to provide selection from four combinations of plate, screen, and grid
voltages. The plate and screen voltages selected are applied through the MERIT switch to the
corresponding position contacts on lever switches 1through C. The grid voltage selected is
applied to the GRID potentiometer so that the desired portion of the total available voltage can
be accurately tapped off by means of the dial calibration and applied to the grid position contacts
on lever switches 1through C, also through the MERIT switch. The plate screen, and grid
voltages selected at each position of the Vswitch are as follows:

667 TUBE TESTER LlEICOL>«PAGE 3
POSITION PLATE SCREEN GRID
145V ~T5V 0-5V
290 45 0-15
3180 90 0-15
4180 90 0-45
LEVER S—This is asingle section six-position switch which selects the value of shunt resis-
tance placed across the meter and PLATE control potentiometer. As such, lever Sis a"coarse"
meter sensitivity control which is used in conjunction with the "fine" control provided by the
PLATE potentiometer. Position 1provides the least meter sensitivity for high current tubes
and position 5the highest sensitivity for low current tubes; intermediate positions provide a
variety of sensitivities necessary for testing the many tube types encountered. At position 6
of the Sswitch, the grid voltage from the Vswitch is connected through the 24, 000 ohm current-
limiting resistor in testing light-duty diodes.
PUSH-SWITCHES 1through 12 &C—Each of these switches serves as atransfer switch for
the tube element connected to the corresponding base pin number. The No. 1switch controls
all connections to the No. 1socket terminals; the No. 2switch controls all connections to the
No. 2socket terminals; and so forth, in order, through to the No-. 12 switch for the No. 12
terminal of the COMPACTRON socket. The Cswitch controls the connections to the cap lead.
These push switches serve the following functions:
With the MERIT and LINE switches at their normal position, depressing one of these switches
transfers the corresponding tube element to one side of the ohmmeter circuit (with the remaining
tube elements all grounded together with the other side of the ohmmeter circuit) as required
for the inter -element leakage tests. These push-switches are also primarily responsible for
two of the outstanding features of this tube tester; one feature being that in the majority of cases
all sections of multi-section tubes draw their normal current when any one section is tested;
the second being the rapid testing afforded multi-section tubes due to the saving in set-uptime.
These advantages are obtained because the push switches permit selection of the tube base pin
which will be connected to the transformer power supply through the meter circuit when the
MERIT switch is pulled down, in order that the current through the corresponding tube element
(normally the plate of atube or atube section) be measured for MERIT testing. The remaining
tube base pins (connected to the push switches which are not depressed for the particular MERIT
test) are connected either directly to the transformer power supply or indirectly through a
potentiometer.
RESET push button —This button is aconvenience intended to permit restoring of adepressed
push-switch to the normal position.
H-K LEAKage push switch —This is amomentary switch which is used for heater -cathode
leakage testing. When the push switch for an indirectly heated cathode (underlined in the LEAK
column of the roll chart) is depressed to transfer the cathode to one side of the ohmmeter circuit,
the H-K LEAK button is depressed also to break the ground connection of the remaining "lumped"
elements in order that cathode emission current to these elements will be excluded from the
cathode heater leakage measurement.
TRANSISTOR TEST selector —This is aspecial five-position multi-circuit switch performing
the following functions: a) At the TUBE position the transistor test socket is de-energized and
the meter connected so as to render it available for line adjustment, leakage testing, and merit
testing; b) At the transistor test positions, it applied adc bias voltage between the collector and
emitter socket terminals, of polarity depending on whether the n-p-n or p-n-p positions are used.

PAGE 4‘
-jEWQL, 667 TUBE TESTER
At the 1position for either transistor type, the meter is inserted in the collector circuit
in series with aIK current-limiting resistor to measure the current (Iceo)under these conditions.
At either 2position, a200Kresistor is connected between the collector side of the power supply
and the base to put asmall current into the base. The current gain, Beta, is then read on the
meter, which remains in the collector circuit.
WARNING: Be certain as to the type of transistor (n-p-n or p-n-p) you aretesting. Testing
atransistor using the positions designated for the opposite type may damage the
tester meter or the transistor. Note that shorted transistors may cause the
meter to read past full scale at the "N-P-N 1" or "P-N-P 1". Should this
occur, turn the switch back to the "TUBE" position immediately and discard
the defective transistor, after you have first checked to see that the correct
test position was used for the particular type.
SPECIAL SOCKET CONNECTIONS —Several socket terminal connections are not standard and
should be noted. The pilot light socket in the center of the NOVAR socket is connected across
the selected filament voltage (shell to ground, center post to filament switch arm). The center
of the loctal socket is connected to ground. The sub-miniature in-line socket has no numbers
assigned to its seven terminals. In the Model 667, these terminals are connected to the push-
switches as if they were numbered 1to 7beginning at the index dot on the panel. However, a
consistent connection procedure has been established (the roll chart settings are given accord-
ingly), which is as follows: With tube base and socket indexes matched (dot or spur on tube
base to dot at right of socket on the panel), the tube leads are inserted in order so as not to skip
any socket terminals starting from the extreme right.
OPERATING INSTRUCTIONS
PRELIMINARY STEPS FOR TUBE OR TRANSISTOR TESTING
1. Insert the power plug in a105-130 volts AC, 60 cps line outlet. Do not use aDC line
outlet or any AC line outlet other than specified above.
2. Turn the tester on by rotating the LINE ADJ. control clockwise from AC-OFF.
3. Set the TRANSISTOR TEST selector to TUBE, regardless of whether it is atube or
transistor that is to be tested.
4. Make apreliminary line adjust by holding down the LINE button while turning the LINE
ADJ. control until the meter pointer is over the LINE ADJ. mark on the meter (center scale).
Release the LINE button at the conclusion of the adjustment.
TUBE TESTING CONTINUED
5. Press the RESET button to release anybutton which may be down from aprevious setting.
Make sure the TRANSISTOR TEST selector is set at "TUBE".
6. Move all 15 lever switches down to the "1" position.
7. Rotate one or both roll chart wheels until the tube type you wish to test appears in one
of the windows. Obsolete types will be found in asupplement to this manual.

667 TUBE TESTER ‘
lEICQL, PAGE 5
8. Note the number of lines of settings devoted to the tube in the chart. Each line of
settings corresponds to asection of the tube (1 line for asingle diode, triode or pentode; 2lines
for adouble diode, triode or pentagrid converter; 3lines for aduodide-triode, etc.) Each
section of the tube is tested by making the settings indicated on asingle line of the chart and
then depressing the MERIT lever. Note, however, that twin or triple section tubes having
identical tube characteristics will occupy one line with two or three plate numbers in the merit
column instead of the usual single number. Each of these numbers signifies an individual merit
test. Using the same line of settings, perform each individual merit test.
EXAMPLE: 12AT7, twin triode
In the merit column you will find the entry 16 (one, six). Press 1to read merit of the
first triode. Press 6to read merit of the second triode.
All interelement leakage testing must be performed before any of the Merit tests, as a
safeguard to the tube tester. The push-button which must be pressed down to complete the
leakage and short testing are all given in the same line or different lines for different sections
of the tube. Specific instructions for making settings and performing the required tests follow.
9. The first 3settings following the tube type are for the FIL. selector, GRID control and
PLATE control, in that order. Set these controls accordingly.
10. The next 15 settings are for lever switches 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, C, Vand S
in that order. Set these levers accordingly.
11. Check all settings to make sure that no mistake has been made.
12. Insert the tube into the socket which matches its base. (The socket just above the
TRANSISTOR TEST selector is for transistors only. All other sockets are for tubes only). If
the rectangular sub-miniature socket is used, turn the tube so that its index (red dot, black dot,
glass spur) matches the dot on the panel; then insert each lead into asocket terminal in order,
not skipping any socket terminals starting from the right. If there is atop cap on the tube,
connect it with the cap clip lead.
13. Allow sufficient warm-up time before proceeding. For battery-operated tubes and
h. v. rectifiers (1B3 type) warm up is almost instantaneous; for most receiving tubes 10 to 20
seconds; for high power pentodes, triodes, and rectifiers 20-40 seconds. Note that the MERIT
test (step 17) should not be performed until the stated warm-up time has elapsed.
14. Press the LINE button and note the meter reading. Depending on the filament drain
of the tube under test, the meter will read more or less to the left of the LINE ADJ. mark
(center scale). Holding the LINE button down turn the LINE ADJ. control until the meter
pointer is again over the LINE ADJ. mark. Release the LINE button at the conclusion of this
adjustment.
15. Refer to the first (or only) line of settings for the tube and note the buttons listed in
the LEAK column. Press down each of the buttons listed one at atime (in order), observing
the meter each time. (See next paragraph for evaluation of leakage readings. )The underlined
leakage buttons are for indirectly heated cathodes; when these buttons are depressed, the re-
sulting meter reading will be valid only when the H-K LEAK button is also depressed. Failure
to do so will not normally cause damage to the tube, but will give too low aleakage resistance
reading due to emission to other elements. Thus, the underlined leakage tests are of heater to
cathode leakage only.

PAGE 6««<«««< liE/CQL1667 TUBE TESTER
On cathode leakage test of light duty diodes in multi-section tyibes, meter will not swing
across the scale as for other type of tubes if tube under test is good, and there is no need to
depress the H-K LEAK button. Underlining of pin No. 2in case of 6AQ7 merely indicates
cathode. The above also applies to other tubes of similar types such as 6R8, 6S8, and 6T8.
Standard for acceptance of rejection on Inter-Element Leakage (excluding cathode -heater
leakage): No less than 5megs on any test. Astricter standard for high reliability applications
would be no less than 10 megs on any test.
Standard for Acceptance or Rejection on Cathode-Heater Leakage: Not less than 1megfor
non-power types; not less than 500K for power types. Half these values may be acceptable for
tubes approaching end of life, with the exception of tubes used in audio preamplifiers which may
not read less than 1meg at any time.
In general, tubes failing to meet these standards should be discarded. In any case, do not
perform aMERIT test on any tube having an inter -element leakage resistance less than 100K
ohms, as this may damage the tube tester. Note that all required inter-element and cathode-
heater leakage tests for the entire tube have been completed with the tester set up for the first
(or only) MERIT test and before the first (or only) MERIT test is made. No further leakage
testing is performed thereafter.
Note: Depressing the buttons listed in the MERIT column actually tests that element for
leakage until the MERIT lever is depressed. Atube giving too low an ohms reading
in this condition should not be tested for MERIT.
16. Perform the first (or only) MERIT test on tubes which have been found satisfactory as
to leakage and shorts by first pressing down the button listed in the MERIT column and then
pulling down the MERIT lever switch. With the MERIT lever held down, read the merit (quality)
indication on the DIODES GOOD scale for diodes and rectifiers, or the colored areas and percent
markings for all other tubes. Note that although 100% represents normal conductance for anew
tube, some tubes will read higher and some lower because of the tolerances allowed in tube
manufacturing. Note also that the limits of the GOOD, ?(doubtful), and REPLACE areas are
obtained by striking an average for all tube types and so should not be interpreted in an absolute
manner.
17. If there is more than one line of settings for the tube, leave the tube in the socket and
proceed as follows for each line: a) Reset the lever switches and GRID and PLATE controls
accordingly; b) Depress the button listed in the MERIT column; c) Pull down the MERIT lever
switch to read the quality on the meter of the particular tube section under test.
18. After testing the last section of atube, remove the tube from the socket of the tube
tester. Push reset button and return all lever switches to "1". Failure to do this can result
in damage to the meter when you proceed to test the next tube.
19. Proceed with testing another tube by beginning with Step 5. If there are no more tubes
or transistors to be tested, turn the LINE ADJ. control counter-clockwise to its AC-OFFposi-
tion. Aslide switch at the end of the potentiometer winding opens the primary circuit of the power
transformer and turns the tester off. If there is atransistor to be tested, proceed directly to
step 5of TRANSISTOR TESTING after completing step 18 of TUBE TESTING.

667 TUBE TESTER t-jEICQL1«PAGE 7
CONTINUE PROCEDURE FOR TRANSISTOR TESTING (From Step 4, Page 4)
5. Locate the type number of the transistor to be tested on the transistor chart. Note
whether the transistor is an-p-n or p-n-ptype and the specified allowable range of Beta. Make
sure that the TRANSISTOR TEST selector is set at "TUBE".
6. Insert the emitter (E), base (B), and collector (C) lead of the transistor in the corres-
ponding terminals of the transistor socket located immediately above the TRANSISTOR TEST
selector.
7. Turn the TRANSISTOR TEST selector from "TUBE" to position Ion the p-n-p or n-p-n
side depending on the type of transistor under test. The indication on the meter will be propor-
tional to the collector current with emitter grounded and no base signal. On this test, transistors
in good condition should read in the "Iceo GOOD" area (between 0and 40 on the 0to 140 scale).
Reject transistors that read outside the "Iceo GOOD" area (higher than 40 on theO to 140 scale),
unless note has been made on the chart that ahigher reading is acceptable.
8o Turn the TRANSISTOR TEST selector to position 2and read the current amplification
factor or Beta (change in collector current caused by achange in base current) on the 0to 140
Beta Scale. Agood transistor will read within the allowable range of Beta as given on the chart
for the particular transistor type. Transistors which do not give areading within the specified
allowable range of Beta may still be useable; see data sheet.
9. Turn the TRANSISTOR TEST selector back to "TUBE" and then remove the transistor
from the transistor socket.
10. Proceed with testing another transistor by beginning with step 5. If there are no more
transistors or tubes to be tested, turn the tester off by turning the LINE ADJ. control to its
AC-OFF position. If there is atube to be tested, proceed directly to step 5of TUBE TESTING
after completing step 9of TRANSISTOR TESTING.
NOTE: The only controls having any effect in transistor testing are the TRANSISTOR TEST
selector, the LINE ADJ. control, and the LINE push-button. Provided that atube
has not been left inserted in any of the tube sockets, the settings of any other lever
switches, push-buttons or potentiometers on the panel have no effect and are
immaterial.
CIRCUIT DESCRIPTION
It may be of assistance in understanding the functioning of the instrument to examine the
following typical partial schematics, each of which indicates the voltages appliedand the place-
ment of the meter circuit when performing the tests provided (in accordance with the detailed
operating instructions) for tubes and transistors.
NOTE:' Rs denotes the meter shunt resistance selected by S29 (Lever S). 01, 02, and
03denote various a-c voltages taken from taps on the high voltage secondary winding of the
power transformer and selected by S28 (Lever V). An asterisk denotes the function of current-
limiting.

PAGE 8«««««««< ^BiCQln 667 TUBE TESTER
The functioning of the Model .667 in each of the various tests furnished is as follows:
INTER-ELEMENT LEAKAGE: Afiltered dc test voltage of -70 volts is obtained by rectifying
and filtering (CR1 and Cl) the 50 volts ac obtained from filament winding tap. This voltage is
applied between the tube element isolated by its transfer switch and the remaining tube elements
whose lever switches are set at the plate, screen, and grid voltage busses which are grounded
through the MERIT and H-K switches at their normal positions. The current through this
circuit is read in ohms on the meter. Note that the polarity of the test voltage is evidently such
as to eliminate cathode emission from the reading and that resistor R8and LEAK CAL. rheostat
R7 restrict the total current to 200ua (full scale) even with adead short. For heater-to-cathode
leakage testing, the connection of the "remaining" elements to ground is broken by depressing
the H-K push-switch to remove them from the circuit and leave in the test circuit the cathode
and heater only. This is necessary because the cathode is placed at anegative voltage with
respect to the "remaining" elements when it is selected by its transfer switch and the consequent
cathode emission current would also register on the meter to give afalse low reading of cathode-
heater leakage resistance.
LINE ADJ: For the adjustment, resistor R19 and LINE CAL rheostat R18 (identical to R8 and
R7 respectively) are inserted in the leakage test circuit by depressing the LINE push-switch to
exactly double the total resistance in the circuit and reduce the meter indication to exactly half
scale. The condition for full-scale and half-scale reading, set in initial calibration with the
LEAK CAL. and LINE CAL. rheostat R7 and R18, is that the LINE ADJUST potentiometer be
set to give 130 volts across the full transformer primary (or 105 volts across the low end of the
primary and the primary tap). The LINE ADJUST potentiometer permits duplication of this
condition over a±10% variation of the actual line voltage from the nominal value (117 volts).
MERIT TEST: Several of the many configurations that occur in MERIT testing are shown above.
In general, each test furnish acomposite indication of cathode emission capability and the
ability of each grid to control the plate current in accordance with the design of the tube, plus
the ability of the plate to receive the regulated current. For diodes and rectifiers, the mea-
surement is simply an emission test. To properly test agreat variety of tube types, several
plate, screen and ranges of grid voltage are available from taps on the plate secondary winding
of the transformer for selection by switch S28 (lever V). These voltages are applied through
switch S34 (MERIT) to the plate, screen, and grid bus bars inter -connecting corresponding
terminals on switches S15 through S27 (lever switches 1through 12 &C). The grid voltage is
variable by R16 (GRID potentiometer) from zero to maximum of the range selected. Note that
the plate, screen, and grid voltage contacts on switches S15 through 27 are grounded at the
normal position of S34 and that plate screen, and grid voltages are only applied when S34 is
pulled down.
o
"70V~
+
O—
-
ci
TO 50V TAP
LEAKAGE TEST POWER SUPPLY -Also used for Line Adjust

667 TUBE TESTER "lE/CQl-, <PAGE 9
TRANSISTOR TESTS: At the P-N-P 1or N-P-N 1test positions of the TRANSISTOR TEST
selector, ameasurement is made of the collector current that flows when the emitter is grounded
and no signal is applied to the base. This currentis afunction of the temperature, the resistivity
of the germanium and, most important, becomes quite large if there is contamination of the
surface of the germanium or if the transistor has been damaged by ashort circuit. At the
P-N-P 2or N-P-N 2position, asmall current is put into the base via the 200K£2 resistor R3
to permit measurement of the collector -to-base amplification factor Beta, sometimes called
Alpha cb. In some cases the range of Beta given in the chart has been taken directly from the
transistor manufacturer’s specification; in other cases Beta has been calculated from the
grounded-base Alpha, Alpha ce, according to the relationship.
Alpha ce
Beta =1-Alpha ce
These simple tests will determine if the transistor is good or bad, but will not, of course,
duplicate the factory tests of frequency response, input resistance, output resistance, collector
capacitance and other electrical characteristics that are necessary for aspecific grade of
transistor.
CR2
TRANSISTOR TEST POWER SUPPLY

PAGE1
0
667 TUBE TESTER
-70V -70V -70V -70V
R8+R7 R8+R7 R8+R7 R8+R7
>7)« y/<
.TO FIL.VOL. TO FI L. VOLT. TO FIL.VOLT. TO FIL.VOLT.
a) CATHODE-TO-HEATER b) PLATE-TO-ALL c) SCREEN-TO-ALL
LEAKAGE TEST LEAKAGE TEST LEAKAGE TEST d) GRID-TO-ALL
LEAKAGE TEST
-70V
R8+R7
A
RI9 +RI8
RI6
GRID
4>‘
R9
PLATE
(|)2
d)3
Rs
4)1
+
(9
Ml
R9
PLATE
(J)2
RI6
GRID
TO FIL.VOLT. “TO FIL.
VOLT.
e) LINE ADJUST f) MERIT TEST OF
TYPICAL PENTODE g) MERIT TEST OF TRIODE
1of aDUO-TRIODE

667 TUBE TESTER ^EICQL
,«page 11
2of aDUO-TRIODE
j) MERIT TESTING
of OZ4, OY4 cold-
cathode gas rectifiers
(test of one section of
OZ4 shown).
117 VAC FROM
FIL.WDG. IN PHASE
WITH <J> ITO
PROVIDE SUF^ ,
FICIENT ^VVV
VOLTAGE FOR
INITIATING <
CONDUCTION
RIG
GRID
^0tVW
R9 PLATE
tofil. 1—VW
VOLT. Rs
Ml
i) MERIT TEST of light-duty diodes, (showing
one diode section of atriode duo-diode, such
as a12SQ7).
<D' 1) MERIT TEST for O0I
power rectifier sec-
RI7* tion Bof full-wave \RI7*
type.
4
TOFIL
VOLT.
k) MERIT TEST for power rectifier
section Aof full-wave type.

PAGE 12 ‘
iEICCJL-i 667 TUBE TESTER
FIL. VOLTAGE
CONNECTED IN
PHASE WITH <J> ITO
PROVIDE CORRECT TOTAL
VOLTAGE FOR TEST
m) MERIT TESTING of OB2, OB3, OC3,
&OD3 VR tubes.
COL
BASE
R4 Ml
.. XN-p-N
P-N-P EMITTER
n) TRANSISTOR TEST 1
(leeo)
AMr
R4 ^o
E
BASE! *
'K N-P-N
P-N-P NEMITTER O
o) TRANSISTOR TEST 2(Beta)
MAINTENANCE
GENERAL: Included in this section are instructions for internal adjustments, trouble-shooting,
and part replacement. All internal adjustments must be performed in the order given on com-
pleted kit instruments before they can be placed in use. The same procedures will serve for
periodic readjustments in both kit and factory-wired instruments when required by component
aging or replacement.
REMOVAL FROM CABINET: To remove the instrument from the cabinet, first disconnect it
from the power line and remove the 14 screws around the edges of the panel which fasten it to
the flanges of the cabinet. As all components are assembled to the panel, removal consists
simply of lifting the panel out of the cabinet.
WARNING: The operator is exposed to voltages as high as 300 volts A-C when the instru-
ment is being operated outside of its cabinet. Take caution to avoid personal
contact with these voltages
INTERNAL ADJUSTMENTS: a) Disassemble the panel from the cabinetand lift the instrument
out. b) With the instrument in its normal operating position and no power applied, adjust the
reading of the meter pointer to zero by turning the mechanical adjustment screw on the meter
face, c) Connect an a-c voltmeter of any type across the 0-130V taps of the power transformer

667 TUBE TESTER "lE/CO^ '< PAGE 13
and insert the line plug into a105-130 volts AC, 60 cps line outlet. With no tube or transistor
inserted in the test socket, and the TRANSISTOR TEST selector set at "TUBE", rotate the
LINE ADJ. control R1 until the voltmeter reads 130 volts AC. d) Depress push-switch "C” so
that it latches, and hold the metal clip on the cap lead against the panel so that it makes good
electrical contact. Adjust the internal LEAK CAL. control, R7, for full-scale deflection on
the meter (zero ohms on the leakage scale), e) Release the "C” push-switch by depressing
the RESET push-button. Now depress the LINE push-switch and hold it down (this switch does
not latch) while adjusting the LINE CAL. control, R18, for half-scale deflection (the short verti-
cal "Line Adjust" on the meter scale). This completes the calibration of the instrument.
NOTE: The LEAK CAL. control, R7, is located on the underside of the chassis near the
FILAMENT selector switch. The LINE CAL. control, R18, is also on the under-
side of the chassigvtj'near the LINE ADJ. control.
i?--
CLEANING TUBE &TRAiptSTOR SOCKET TERMINALS: After along period of time, afilm of
dirt may form on the ietSIde contact surfaces of the socket terminals which will prevent good
contact with the inserted tube and transistor pins or leads. Spray or pour alittle contact cleaner
through the socket terminals, if this condition occurs, to remove the dirt film andrestore good
contact surfaces.
FUSE REPLACEMENT: Afuse in series with the primary winding of the power transformer
protects the tube tester against damage due to overloading. Do not replace ablown fuse until
you have located and corrected the cause of the failure, which can be any one of the following:
a) incorrectly set controls; b) voltage applied to shorted elements; c) ashort developed with-
in the circuit of the tube tester. In the last case, it will be necessary to use the schematic diagram
to locate andremedythe source of trouble. Note that the fuse is atype 3AG 1ampere and thatis
mounted in afuse clip on the side of the bracket supporting the power transformer. Do notuse
ahigher ampere rating fuse type for replacement.
ROLL CHART MECHANISM: a) Springs: Asmall spring inside the roll chart mounting bracket
provides asmall tension against the bottom of one gear wheel to hold the rollchartin any posi-
tion to which it is set. Excessive tension will impede fast rotation of the wheels when seeking
tube information, and insufficient tension will result in a tendency of the roll chart to move
from the set position. If necessary, reset the spring to provide the slight tension against the
wheel required for satisfactory operation, b) Center shaft clips: There are speed-nut clips
on either end of both center shafts that press against the outer wheel surfaces and hold the
tube-and-wheels assemblies together. If these clips slip out of the shaft, the assemblies will
become loose. Should this occur, it will be necessary to unscrew the bracket from the panel
and remove the roller assemblies. Then press the clips against the outer wheel faces.
AVAILABILITY OF NEW TUBE &TRANSISTOR TEST DATA
ROLL CHARTS AND SUPPLEMENTS
As new tube and transistor types are released, an adequate number of samples of each
type are carefully tested and rated in the EICO laboratories to establish the correct control
settings for testing with the Model 667.
Periodically, new roll charts will be made available that include these new settings. With
each new roll chart, acumulative supplement of testing information on obsolete and rarely used
types will also be supplied. When necessary, interim supplements of new testing information
may also be made available.

PAGE 14 <<<««<« L-}EICOl-]667 TUBE TESTER
NOTE: By filling out and returning toEICOthe registration card included with each instru-
ment, the owner can be assured of notification when new charts and supplements
are made available.
USING INTERIM SUPPLEMENT OF NEW TUBE INFORMATION
The new testing information contained in interim supplements, which may be available from
time to time, can be easily entered on the roll chart in current use as follows: a) Rotate the
wheel to the blank space left on the roll chart for this purpose; b) Lift the plastic window out
of the panel. (It snaps out of place); c) Enter the new data on the roll according to the headings
lettered on the panel; d) Carefully check to see that you have made the entries correctly;
e) Push the plastic window back into the panel again. It will snap into place.
ROLL CHART REPLACEMENT
Any new roll chart will include new testing data from previous interim supplements plus
any additional testing data obtained up to the time of publication; all new types will appear in
their proper positions on the new roll chart.
TAPE ALONG
THIS EDGE
ROLL CHART
(NOTE ORIENTATION
OF CHART)
ROLL CHART
BRACKET
ROD
NO.6-32
TINNERMAN NUTS
ROLLER
GEAR
FRONT PANEL
NO.6-32 SCREW
ROLL CHART ASSEMBLY

667 TUBE TESTER *7E/CO <PAGE 15
To install the roll chart, unfasten and lift out the panel assembly (the entire instrument)
release both rollers and remove the rollers from the bracket. Install the new chart as follows:
a) Fasten the top end of the chart to one roller with good quality adhesive tape. The printed
surface of the chart must face away from the roller; b) Wind the chart onto the roller carefully,
being certain that it does not wrinkle or bind on the side wheels; d) Place the other roller
under the one on which the chart is wound so that adjacent gears mesh —then pass the bottom
end of the chart through the opening between the rollers and fasten it to the surface of the lower
roller with another piece of adhesive tape (pull the chart tight onto the lower roller when you
fasten the end to it); e) Insert the pair of rollers in the roll chart bracket with the full roll
toward the open side, which when mounted is closest to the panel; f) Mount the bracket on the
front panel with the four screws which were removed at the beginning of the replacement steps;
g) Finally, check to see that the bracket has been mounted so that the printing on the chart
reads right side up and that turning the wheels to roll the chart through its entire length does
not reveal any binding on the wheels or the chart paper.
SPECIAL APPLICATIONS
CHECKING PILOT LAMPS AND CHRISTMAS TREE LAMPS
In the center of the NOVAR socket is areceptacle for miniature-base lamps. It is suitable
for either screw or bayonet base types, since both have center contacts on the end of the base
and shells around the side of the base to serve as the other contact. As the wall around the
receptacle is grounded and the center contact of the receptacle is connected to the rotor of the
FILAMENT selector switch, whatever filament voltage is selected will be applied to aminiature -
base lamp inserted in the receptacle for testing. The test procedure, therefore, is the following:
a) Set the FILAMENT selector to the rated voltage of the lamp; b) Depress the LINE button and
turn the LINE ADJ. potentiometer until the meter reads at the LINE ADJ. mark on the scale;
c) Insert the lamp in the test receptacle. Agood lamp will light to its normal intensity.
DEVELOPING SETTINGS FOR NEW TUBES
Paragraphs athrough kcover the procedure for all single triodes and pentodes. Paragraph
Igives the procedure for half-wave rectifiers, and paragraph mthe procedure for light-duty
detecting diodes (usually in the same envelope with atriode or~pentode). Paragraph ndeals
with testing dual-triodes, triode -pentodes, and full-wave rectifiers. ~
a) Set the TRANSISTOR TEST selector to '’TUBE".
b) Set the FILAMENT selector switch to the required filament voltage. For center-
tapped heaters, use the series connection with the higher filament voltage (see step c).
c) Set lever switches 1through 12 and Cto positions which will connect the proper
source of voltage to each tube element. Levers 1through 12 set the connections
for base pins 1through 12 respectively, and lever Csets the connection for the cap
lead. The positions of the switches are as follows: 1is ground; 2is filament; 3is
screen or optional plate; 4is plate; 5 is control grid; and 6is open (no connection).
The following rules must be observed: 1) One side of the filament must be grounded;
filament taps must be connected to position 6; 2) For tubes having several pins
connected to the same element, connect only one of these pins to the appropriate
voltage (or ground, in the case of acathode); all other suchpins must be connected

PAGE 16 «««««« l~iEICQL1667 TUBE TESTER
to position 6; 3) Connect all unused pins and internal shields to position 1(ground)
unless otherwise specified by the manufacturer; 4) All detecting diode plates (such
as in the 6SQ7) must be connected to position 6; 5) For tubes having amaximum
allowable DC plate voltage less than 70 volts, position 3must be used for the plate.
d) Insert the tube in the socket and allow it to heat up. Make the line adjustments in
the usual manner. Then determine the push-buttons to be pressed in the leakage
tests by consulting the base diagram of the tube and selecting the pin numbers which
correspond to the elements. If the tube has an indirectly heated cathode, note which
pin number is the cathode (for heater -cathode leakage testing;. The pin numbers
so determined correspond to the numbers of the push-button switches to press for
the leakage tests. Enter the numbers of these push-buttons in the LEAK column of
the roll chart, underlining the cathode button. It may be convenient to refer to a
similar tube type in making these settings.
e) If the leakage tests described above show the tube satisfactory, proceed with the
MERIT test procedure. If the leakage test results are unsatisfactory, do not
proceed with further testing on the faulty tube, or the tube tester may be damaged.
f) Refer to the base diagram for the tube and determine the pin number for the plate.
This push-button number should then be listed in the MERIT column and should
correspond to the lever which you had set to position 4(step cabove). Press this
button, remembering that this constitutes aplate-to-all leakage test until the MERIT
lever is pulled down.
g) Refer to the published characteristics of the tube to find the maximum allowable
plate current, or the highest typical operating current listed. Locate this plate
current in one of the charts 1-5. Read the corresponding settings of the PLATE
control and the chart number. Set lever Sto the chart number, and the PLATE
control to the value as read from the chart. Doing so establishes that the meter
will read 100 on the scale when the plate current of the tube is equal to the desired
value.
h) Consult the published tube characteristics again and find the maximum allowable
dc plate voltage. Note that lever Vapplies 45 volts atpositionl, 90 volts atposition
2, and 180 volts at positions 3and 4(all in volts rms, 60cps). The highest position
of the Vlever that may be used is the one at which the rms plate voltage applied
does not exceed roughly two-thirds of the maximum rated dc plate voltage.
i) Set lever Vat position 1and the GRID control at 7. Hold down the MERIT lever
and note the meter indication. Increase the GRID control until ameter indication
of 100 is obtained. If this is not possible, release the MERIT lever, return the
GRID control' to 7, and advance the Vlever to position 2. Again hold down the
MERIT lever and adjust the GRID control for ameter indication of 100. Continue
this procedure, setting lever Vto positions 3or 4, if necessary, to obtain the 100
meter indication. If the GRID control appears to "saturate", that is, if an increase
in its setting causes very little increase in the meter indication, lever Vshould be
advanced to the next position. Be careful not to exceed the maximum allowable
plate voltage when making this setting. For the new 12 volt automobile radio types
(30 volts dc maximum plate voltage), set the plate element lever to position lonly.
When the correct Vlever and GRID control settings are found, release the MERIT
lever and remove the tube from the tester.

667 TUBE TESTER "lEICQL, »< PAGE 17
"PLATE" CONTROL SETTING 20 40 60 80
“PLATE" CONTROL SETTING
NOTES: 1. These charts show the actual tube (plate or screen) currents drawn when the
meter reads 100 on the 0-140 scale. For any other meter readings, multiply
the indicated currents (from the appropriate chart) by the fraction X/100, when
Xis the actual meter indication*
2.
Chart 1is used when the "S" lever is set at position 1, chart 2is for position
2. chart 3is for position 3, chart 4is for position 4, and chart 5 is used for
positions 5and 6.
3. These charts are to be used for "MERIT" testing of tubes only; they do not
apply for line adjustment, leakage, or transistor tests.
4. Normally, only plate currents are measured. However, screen currents can
be checked in the same manner by depressing the push-button corresponding to
the pin number of the screen (substitute this number for the one shown in the
MERIT column of the roll chart). Then pull back on the MERIT lever and read
as above.