BLACK STAR APOLLO Series User manual

Blaclc. ♦ Star
APOLLO
SERIES OF UNIVERSAL COUNTER TIMERS
APOLLO 10
APOLLO 100
APOLLO 100 UNIVERSAL COUNTER-TIMER
APOLLO 10X
APOLLO 100X
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Service Manual

SPECIFICATION
INTRODUCTION
FUNCTIONAL DESCRIPTION
CIRCUIT DESCRIPTION
VOLTAGE CONVERSION
CALIBRATION
TROUBLE SHOOTING AND
FAULT FINDING GUIDE
PARTS LIST
DIAGRAMS:
INDEX
MECHANICAL ASSEMBLY
FUNCTIONAL BLOCK DIAGRAM
COMPONENT LAYOUT MAIN PCB
COMPONENT LAYOUT PREAMP PCB
COMPONENT LAYOUT FRONT PANEL PCB
COMPONENT LAYOUT SUB BOARD PCB
1
2
2
5
8
9
10
11
3
4
15
16
17
18
CIRCUIT DIAGRAMS 1 POWER SUPPLY 19
© 1986 BLACK STAR
2 PRE-AMPLIFIER 20
3 FREQUENCY MULTIPLIER 21
PR ES CALER
4 INPUT SELECTOR 22
STOPWATCH
START/STOP
GATING
5 SLOPE CONTROLS 23
HOLD-OFF
SINGLE MEASURE PRIMING
TRIGGER L.E.D. CONTROL
RESET
DISPLAY HOLD
MAIN COUNTER I.C.
6 SYSTEM CLOCK 24
RPM PRESCALER
7 FRONT PANEL SWITCH LOGIC 25
8 DISPLAY MULTIPLEXERS 26
RANDOM LOGIC
9 FRONT PANEL DISPLAYS 27
10 MISCELLANEOUS SWITCHING 28

TIMEBAS E
Crystal Oscillator Frequency
Time between measurements
Aging
Setability
Temperature Stability
INPUT A
Bandwidth / Sensitivity
Coupling and Input Impedance
Low Pass Fitter
Maximum Input Voltage
Triggering
Attenuat or
INP UT B
B andwidth /Sensitivity
Coupling and Input Impedance
Low Pass Filter
Maximum Input Voltage
Triggering
Attenuator
F REQU EN CY A
Gate Tim es
Ranges/Resoluti on
Accuracy
FREQU ENCY RA T IO A TO B
Frequency Maximum
Ratio Averaged Over
Resoluti on
Ac cu ra cy
PERIOD A
Measurement Type
Per io d Range
Display
Period Averaged Over
Resol uti on
Ac curacy
TIM E INTERVA L A TO B
Range
Display
Minimum Pulse Wi dth
Maximum Frequency
Time Interval Averaged Over
Resolution
Accuracy
SPECIFICATIONS
APOLLO 10 APOLLO
10X
APOLLO 100 APOLLO 100X
10MHz
200ms nom. Adjustable 200ms to 10 sec. nom . (HOid Contrell
<::t 5ppm /year <::t lppm / year
<::t 5Ppm / year
<:t lppm /year
<.0 .Sppm <~ .2ppm <.O .Sppm
<:0 .2ppm
::t 10ppm -10°C to + 70°C < z
lppm
::t l()ppm -10°C to + 70°C <
::t lppm
0°c to so
0c
0°c to so
0c
10MHz range <
SmV DC - 10MHz
100MHz range <10mV 1MHz -00MHz
< 30mV 50MH z - 100MHz
DC@ 1 MU // 30pF; AC@ 1M {l / /30pF ; SOU
Coupling DC; c ut - off frequency S()kHz nom .; switch selectable
AC Coupling : 50V DC or 250V rm s@ 50Hz decreasing to 5V rms@ >70kHz; DC Coupling : 300V DC
Level adjustable, + ve or -ve edge; L.E.D.·s Indicate when triggered
xl, xl0 switchable
<SmV DC - 2 MHz
DC@ 1M {l / /30pF; AC@ 1MQ/ /30pF; son
Coupling DC; c ut - off frequency SOie.Hz .; switch selectable
AC Coupling: 50V DC or 250V rms@ 50Hz decreasing to 5V rms@ >70kHz; DC Coupling: JOOV DC
Level adjustable, +ve or -ve edge; L.E.D.'s indicate when triggered
xl , xl0 switchable
0. 01 sec.; 0.1sec .; 1sec. ; 10 sec.
·: ·::.·.·:::.·::. ·::: ·: ·:::: ::: :
Mult1pl1 er
6Hz - 10kHz 10 . 01 + Gate Time) Hz*
Mult iplier
·::
14Hz -100kHz
10 .1 + Gate TimeI Hz*
DC -10MHz (1 + Gate Time)
Hz
1MHz -100MHz I 10 + Gate Time) Hz
..
...
..
.•:•:• . ·.·.· . ·.·.·.·.•.•: ·. · .·. · .· . ·.· .· .· . ·.·.· . -:·:·: ·: ·. ·. I PSC (1()() +
Ga1e Time) Hz
.... .
.. .
.. ... .
PSC + 100 1100 r Gate Time/ Hz
1 •·:· ·: ·· ···· · ············· · ·· · ······· ··· ··::.·.·. ·..·. ·.·.·.· . ·.·.·.· . ·.·.·.· . ·.·.·.
:t(1co unl + timebase accuracy)
Input A: 10MHz; Input 8:2 MHz
1, 10 , 100, 1())) cycles of Input B
1 + no . of cycles of Input 8
:tl count
Single Cycle and Multiple Period Average
5(X)ns - 10 sec.
-·
1, 10, 100, 1())) cycles
100ns + no . of cycles averagect
:tltim ebase accuracy + resolution + ltrigger error• + no . of cycles averagedI)
250ns - 10 sec.
-·
250ns
2 M Hz
1, 10, 100, 1 ())) Intervals
lOOns + no . of intervals averaged
:t(timebase accuracy + resolution + Itrigger error• + no . of intervals averagedII
APOLLO 10 I APOLLO 10X APOLLO 100 I APOLLO
100X
C OUNT A
Count Maximum
Input Frequency
Resolution
Reset
Gating
S TOPW AT CH
Display
Times to
Resolution
Accuracy
Reset
Gating
RP MA
Display
Range
Gate Time
Resolution
Accuracy
EXTE RNAL TI ME BASE OS CILLA TOR
Calibration Frequency
Input Frequen cy Range
Input Voltage Range
Input Load
Output Frequency
Output Drive
EXTE RNAL RESET INPU T
PO W ER REQUIRE MEN TS
DI SPLA YS
ANCIL LARY C ON TROLS
(Front Panel)
Gene ral
Environmental Operating Range
Case
Size
Weight
Supplied Accessories
Optional Accessories
Rear P antH facilities
1.6
•Typical Trigger Error = -
---- -ns
Slope/ (V / µsl
10•-1
10MHzmax .
1 count
Fvternal reset Input Manual !reset
button) or External reset Input
Input B Manual (stop/start
button ) or I nput B
. . . . . . . . ·. ·. ___ • Seconds
. , . ... .;.:::: ·: ::·:·... :. .. : ._ ____ _ ,_o_•_••-~ -;.,,-1>_ ~_, _ da _v_s_l --------1
.·,· •. ·.. t- -- ---- - - --- -------1
:t(timebase accuracy + 10ms)
......... .. ..
. : : : . . . : .. :-: - .· .
Man ual (reset button) or External reset Input
. : ·,· . .
,• ..·... >------ - ---- ---~--
Manual (stop/start button) or I nput B
. .. . . .
. ,:, . :, .
.... -: -. . .: .· . .. ' , '
. : : . . . : : : : : . . . . . . . ~. !: ~.
l()X)'s RPM
.. ·,· . 1
to 10
11 RPM
.. ·.• ·.·. . ... .
..· .•,• .•,:-:-:: : :·: : :-· ,•
0.06 se c.; 0.6 sec.; 6 sec.; 6() sec.
(60 + Gate Time) RPM
..
:tltimebase accuracy + 1 count)
External oscillator in/Internal oscillator out ; swit ch selectable; TT L compatible
10MHz
lOOkHz nom . min. to 10MHz
0V to + 5V max.
1HCMOS Input
10MHz
Sink SmA, source SmA
Active low ; TTL compatible; Input Voltage range ~V max.
Mains operation only. 220 -240V AC 50-60Hz ; 24VA
8 Digit 7-segment 0.5' ' bright L.E.D.'s; automati c decimal point ; leading zero suppression
Unit Indicators for MHz. kHz. se c ., µsec., KRPM; overflow indicator; gate i ndi cators
:: \ Display Hold: adjustable 200ms to 10 sec. nom .
:!; :;; Trigger Hold-o ff : adjustable 5 to 500ms nom .
\ ::>;:'.:'. :; : ~~:~~s~i=~r;::~t.
0°C to + 40°C I 10 % - 80% RH non -condensing)
Custom-moulded, sturdy, lightweight ABS . with tilt stand
219mm x 240mm x 98mm (product only)
310mm x 330mm x 135mm (packed)
2.2Kg (produ ct only) 2.9 Kg (packed)
Mains Lead, Instruction Manual, Spare Fuse
Passive Probes. BNC Cable Assemblies, Service Manual
Power on/ off; spare fuse; External reset Input; External timebase; lnt . Timebase out
* Typi ca lly 5sec . settling time.

INTRODUCTION
1. HANDLING
While the APOLLO counter timers have been
designed to be rugged, severe shocks can be des-
tructive and should be avoided. Do not expose to
radiant heat, including direct sunlight for long
periods, or excessively high humidity. When ser-
vicing suitable precautions should be taken against
static discharge as the unit contains CMOS compo-
nents.
2. TEST EQUIPMENT
(a) Signal generators 2Hz to 100MHz with cali-
brated output.
(bi
(cl
(d)
Frequency standard with an accuracy of
0.05ppm or better.
Oscilloscope with 100MHz bandwidth and
5mV /div sensitivity.
x10, 10M 01oscilloscope probe.
(el 3½ digit multimeter.
3. DISMANTLING
(a) Remove TRIGGER LEVEL, HOLD and HOLD
FUNCTIONAL DESCRIPTION
1. INPUT A
The signal at input A passes through the signal con-
ditioning circuit. This is the x1 /x10 attenuator, A.C.
50 n and D. C. coupling circuits. The signal then
passes to the pre-amplifier where the signal is ampli-
fied, filtered by the low pass filter if required, and the
trigger level is adjusted.
The signal can then follow one of two paths, ( 1)
through a Schmitt trigger squaring circuit or (2)
through an E.C.L. amplifier to provide a suitable
signal for the 100MHz pre-scaler.
The 10MHz output can be routed via the frequency
multiplier to achieve greater resolution when making
low frequency measurements.
The three outputs from the input A amplifier are then
passed to the input A selector.
2. INPUT B
The signal at input B passes through identical signal
conditioning and pre-amplifier circuitry as input A,
with the exception of the E.C. L. amplifier, 100MHz
pre-scaler and frequency multiplier circuits.
OFF knobs by gently but firmly pulling from 3. INPUT SELECTOR
shaft.
(b) Remove tilt stand by pushing firmly inwards on
one side.
(cl Unscrew the four recessed pozidrive screws set
into the feet on the underside of the case.
(di Gently separate the two case halves ensuring
the rear panel remains in the lower case half.
NOTE: If the counter only requires calibration no
further disassembly is necessary. If component
replacement is required then proceed as follows.
(e) Remove the four self-tapping screws securing
the main p.c.b. to the lower case half.
(f) Carefully lift the entire assembly including rear
panel from the lower case half.
(gl Desolder the GROUND connection between
the front and rear panels.
(h) Separate the rear panel from the main p.c.b. by
disconnecting PL401, PL100 and PL101.
(i) Separate the front panel assembly by pulling it
c.way from the main circuit board. Take care
not to bend the connector pins.
(j) The pre-amplifier p.c.b. can now be removed
by gently pulling upwards. Take care not to
bend the connector pins.
(kl Desolder the two B.N.C. connectors and the
GROUND connection from the rear of the front
panel p.c.b.
(I) Remove the front panel from the front panel
p.c.b.
Disassembly is now complete. Reassembly is the
reverse of disassembly.
2
This selects which signal is fed to the main counter
i. e. 10MHz, 100MHz, frequency multiplier or stop-
watch pre-scaler output.
4. INPUT CONTROL CIRCUITS
This section contains the start/stop control logic, the
hold off monostable, single measure priming circuit,
slope selection and input A gating circuit.
5. MAIN COUNTER INTEGRATED CIRCUIT
This is a fully integrated Universal counter and
display driver. It contains all the circuitry necessary
to function as afrequency counter, a period counter,
a unit counter, a frequency ratio counter and a time
interval counter.
The FUNCTION, RANGE, CONTROL and
EXTERNAL DECIMAL POINT inputs are time multi-
plexed to select the desired input function. This is
done by connecting the appropriate digit strobe to
the control inputs F, Rand DP . The control of these
inputs is done by the FUNCTION, RANGE and
EXTERNAL DP multiplexers, which are in turn con-
trolled by the various CONTROL LOGIC circuits and
front panel switches.
6. STOPWATCH PSC
In order to provide the counter with a stopwatch
function the counter is set to the count mode. The
internal 10MHz reference oscillator is divided down
by the stopwatch pre-scaler to produce a frequency

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z
~
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Q)
GREEN /YELLOW
WHITE
I
WHIT
MECHANICAL ASSEMBLY
LJ
LJ
SK12O3 SK12O2
MAIN P. C. B.
I
PRE -AMP PRESCALER
ANO FREQUENCY
MULTIPLIER P.C .B.
C4O2
G)
TC.XO .
ADJUST
LJ'
PL12O1la)
PL12O1lb)
al
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R1269

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of 100Hz. This is then sent to the main counter via
the input selector.
7. R.P.M. PSC
A r. p.m. measurement is performed in essentially the
same way as a frequency measurement but with the
GATE time increased by a factor of six. This is done
by dividing the system clock with the R.P.M. pre-
scaler before applying it to the main counter.
8. ;RESET CIRCUITS
These provide the necessary electronics to reset the
main counter IC by the front panel pushbutton and
the rear panel reset inputs. Internal resets are
generated when a function , gate or range change is
made.
9. 1HOLD/SINGLE MEASURE
This circuit arrangement provides the necessary
signals to the main IC in order to enable the counter
to ( 1) store the result of a measurement and (2)
provide the display hold funct ion.
10. T.C.X.O. and OSC
The standard APOLLO counters are fitted with a high
stability crystal which provides the 10MHz reference
oscillator. The main IC provides a buffered output of
this signal which is the system clock. The circuitry
has the facility to include a temperature compensated
crystal oscillator (T.C.X.O.) to provide higher accuracy .
and stability if required.
SIGNAL
CO NDITIONING
' t{, IN ------1 AC.DC, 50.fl
x1 , x10
+5V2
11. CLOCK SELECTOR
The clock selector circuit selects, using a rear panel
switch, either the internal system clock or an external
clock signal (e .g. an off-airfrequency standard).
12. FUNCTION, RANGE and GATE control logic
This section decodes the function, range and gate
pushbuttons to provide the various control lines.
INPUT
CO NTROL
+ GATE
CIRCUITS
CO NTR OL
SIGNAL
,8, IN -----< CONDITIONING
AC oc, son
X1. X 10
PR E- AMPLIFIER f--------+-----'
4
TRANSFCJR,,1ER
+
REGULATED
N POWER
SUPPLIES
E
+ LO W PASS
F IL TER
- 5V
EXT CLOC K 1/0 ......, .......... _
+5V2
+sv
-s v
ov
DIGI T
STROBES
F RON T
PA NE L
SWITC HE S
FUNCTIONAL BLOCK DIAGRAM
FUNCT IO N GATE
A B
L.S. l.
UNIVERSAL
CO UNTER
RANGE
CO NTR OL
DISP LAY
DIGIT
STROBES
CONTROL
EX T

CIRCUIT DESCRIPTION
The following description applies to the APOLLO 100
counter timer. Certain sections are not applicable to the
APOLLO 10. Refer to circuit diagrams for the differ-
ences. NOTE control signals marked with a' *' are active
low e.g. (* FREQ) .
1. POWERSUPPLY(CCT. DIAG.1)
Three separate voltages are generat ed by the power
supply circuit. These voltages are provided by mono-
lithic integrated circuit regulators IC100, 101, 102 and
their associated components. The +5V2, and the
- 5V supplies are used by the pre-amplifier, pre-
scaler and frequency multiplier circuits. The +5V2
supply is adjusted by RV100 to 5.2V ±0.05V so that
the ECL circuits operate at their optimum voltage.
The + 5V supply is used by the main logic circuits.
Test points TP100, TP101 , TP102 and TP103 are pro-
vided for convenient monitoring of the power
supplies. All three voltage supplies have built in short
circuit protection. The mains transformer T100 pro-
vides the necessary voltage conversion and isolation
of the mains supply voltage. Transformer taps are
provided to enable conversion to 110/120V
operation. Fuse F100 provides protection against
fault currents. SW100 is the instrument ON/OFF
switch arid is mounted on the rear panel.
2. PRE-AMPLIFIERS (CCT. DIAG. 2)
S1200 selects the input coupling mode AC, 50 n, DC
or LPF. With the switch in the 50 n position C1201
and R1200 terminate the input with nominally 50 n,
(the input is DC coupled in this position). With DC
selected the input signal is directly coupled to the
pre-amplifier. R1201 sets the input impedance to
1 Mn. With S1201 in the x10 position the input signal
passes through the x10 attenuator, R1202 and R1203
perform the voltage division and C1202 and C1203
provide frequency compensation.
The pre-amplifier is protected from excessive input
voltage by R1204 , R1239 , C1204 , D1200, and D1201.
The input coupling components are situated on the
front panel sub-board, which is mounted between
the front panel and the front panel p.c.b.
01200, 01201 and 01202 form a high input impe-
dance, wide bandwidth voltage follower. The high
input impedance is necessary to avoid loading the
input coupling and attenuator circuits.
The next stage of the pre-amplifier consists of two
differential amplifiers 01208, 01209 and 01206,
01207. Amplifier 01206, 01207 is operative when the
LPF (low pass filter) is selected. Amplifier 01208,
01209 is operative when AC, 500 or DC is selected.
Normally 01205 is biased on so that the current
source 01203 is connected to the emitters of 01208,
01209, so that this amplifier is operative. Alterna-
tively if the LPF is selected 01204 is biased on and
01205 is biased off so that the current source is con-
nected to the emitters of 01206 and 01207. This
amplifier is then operative and the inputsignal passes
through the low pass network R1213 and C1205
before amplification. The filter components values
are calculated to give a cut of frequency of nominally
50kHz.
The variable resistor R1218 is the front panel
TRIGGER LEVEL control and sets the working point
of the differential amplifiers. Resistor R1219 is
adjusted during calibration to take account of com-
ponent tolerances. The emitter follower 01210
applies the working point voltage to the base of
01206, 01207, 01208, 01209. Diodes D1204 and
D1205 provide temperature compensation for the
trigger level control.
The antiphase outputs from the differential amplifier
provide the input to IC1200(b). IC1200(b) forms the
main gain stage of the pre-amplifier, this IC is an ECI
differential line driver biased to operate in the linear
mode to provide higher gain. The output from
IC1200(b) feeds two circuits (1) a Schmitt trigger ECL
to TTL converter, 01211, 01212 and 01213. 01213
is a high speed switcliing transistor to ensure the
fastest possible rise time. Overall feedback around
this amplifier is provided by R1229 . (2) IC1200(c)
buffers the output of IC1200(b) to provide asignal for
the 100MHz pre-scaler (see CCT. DIAG. 3).
3. FREQUENCY MULTIPLIER AND PRE-SCALER
CIRCUITS (CCT. DIAG. 3)
IC1105 is a + 10 or + 11 pre-scaler. D1103 pulls pins 2
and 3 high to set the pre-scaler to the +-10 mode.
The 10MHz output from the pre-scaler is inverted by
the Schmitt trigger IC1106(b) and sent to the input
selector (see CCT. DIAG. 4).
Channel A output from 01213 (see CCT. DIAG. 3) is
inverted by IC1106(f) and sent to the input selector.
The channel B signal from the pre-amplifier is passed
through IC1106(a,c) and sent to the Gating and Input
B circuits (see CCT. DIAGS. 4and 5).
IC1101 performs level shifting for the input signals to
the frequency multiplier circuit. This is necessary as
the frequency multiplier circuit operates from dual
supplies. The frequency multiplier function is per-
formed by IC1102, IC1103, IC1104 and associated
components, which form a frequency multiplying
PHASE LOCKED LOOP. IC1102 is a phase locked
loop integrated circuit, containing two phase com-
parators, a voltage controlled oscillator (VCO) and a
source follower. IC1103 is a two stage counter which
divides the VCO output by either 10 or 100 and sends
the signal to the phase comparator input pin 3. The
two multiplier ranges are selected by the control lines
(* 100kHz) and (* 10kHz). When the 10kHz range is
selected the gate IC1104(a) is enabled and the divide
by 100 output of IC1103 is sent to the phase com-
parator input of IC1102 to provide a multiplication
factor of 100. When the 100kHz range is selected the
gate IC1104(b) is enabled and the divide by 10 output
from IC1103 is sent to phase comparator input of
IC1102 to provide amultiplication factor of 10.
The phase comparator output (PC OUT) is smoothed
by the filtering components R1107, R1108, R1116 ,
C1102 and C1103 to provide the control voltage for
5

the voltage controlled oscillator (VCO IN). NOTE
C1102, C1103 and R1116 are only in circuit when the
10kHz range is selected, these components are
required to reduce the amount of ripple on the VCO
control voltage when making low frequency measure-
ments to ensure a stable display.
The (FM 1NH) signal (see also CCT. DIAG. 8) is used
as the enable for the multiplier function. When either
the 10kHz or 100kHz range is selected the(* FM INH)
signal goes high and turns off TR1101 causing the
voltage at pin 5 of IC1102 to go low and enable the
frequency multiplier. TR1102 ensures that the filter
capacitors C1102 and C1103 are fully discharged and
that the VCO is operating at its lowest frequency
when the multiplierfunction is selected.
4. INPUT SELECTOR (CCT. DIAG. 4)
The INPUT SELECTOR selects which of the input
signals, 10MHz, 100MHz, FM or STOPWATCH is
sent to the main counter for measurement. IC304 is a
1 of 8 data selector, the three control signals A, B, C
determine which of the inputs are transmitted to the
output (A IN).
The table below shows how the various functions are
selected.
C
H
L
L
L
B
H
H
L
H
A
H
L
H
H
w
07
02
01
03
FUNCTION
100MHz
10MHz
FM (multiplier)
STOPWATCH
5. STOPWATCH PSC (CCT. DIAG. 4)
IC307, IC308 and IC309 form the stopwatch pre-
scaler circuit. The purpose of this circuit is to provide
an accurate 100Hz signal from the 10MHz system
clock (SYS CLK) that can then be counted by the
main counter IC . IC307, IC308 and IC309 are dual + 2
and + 5 counters. IC307 and IC308 are arranged to
each divide 100 and IC309 to divide by 10 to give a
total division by 100,000.
The counters are provided with a clear signal, which
is derived from the (RESET) line. The (CLEAR) signal
ensures that counting always begins on the same
signal edge so that counting errors are avoided.
6. START/STOP and GATING (CCT. DIAG. 4)
The START /STOP button controls the stopwatch
and count functions. The start/stop circuit generates
two signals when the start/stop button is pressed,
( 1) the Q output of IC306 (pin 5) and (2) the (START)
signal from IC708d. IC305 and IC306 give a toggle
action to the start/stop button (S1007). When the
(START) signal is high and (*STOPW + COUNT) is
low then (GATE) is low, which opens the input A
gate and allows counting or timing to begin (see Fig.
5) . IC306 is provided with a (RESET) signal to close
the input A gate and reset the count or stopwatch
when a reset occurs. The (START) signal is also used
to prime the counter when using the single measure
facility.
6
7. SLOPE CONTROLS and HOLD-OFF (CCT. DIAG. 5)
The input signals (AIN) and (BIN) pass through the
exclusive OR gates IC200. Switches ATRIG and
BTRIG, the SLOPE controls, invert the signals to set
the trigger edge to + VE or - VE slope. When the
control signal (GATE) is low IC202b passes the signal
through to be measured by the main counter IC.
signal through to be measured by the main counter
IC.
When making time interval measurements it is some-
times necessary to delay the triggering of input B to
avoid triggering problems. This trigger hold off
facility is accomplished by IC201, IC209 and their
associated components. IC201 is a precision CMOS
timer configured as a monostable. The monostable
period is set by the front panel hold off control
RV1001 and C200. The timing range of the hold off
control is from nominally 5ms to 500ms. The mono-
stable is triggered on by the negative going edge of
the (AIN) signal via C213 .
8. SINGLE MEASURE PRIMING (CCT. DIAG. 5)
Before making a single time interval measurement
the main counter IC205 must be "primed". This is
done by generating a negative signal edge at AIN
(pin 40) followed by a negative signal edge at BIN
(pin 2). The priming signals are generated by the shift
register IC203. The (START) signal is clocked
through the shift register by the system clock and
outputs are taken from pins 3 and 11 to provide the
priming signals. The (SINGLE CYCLE) signal clears
the shift register prior to priming.
9. TRIGGER LED CONTROL(CCT. DIAG. 5)
The front panel trigger level LED's are driven by
signals derived from the signal inputs; to the main
counter IC205. The B signal is first inverted by
IC204b and then sent to the display p.c.b. The gate
arrangement IC208, 204 selects the (10M INP) signal
when the frequency multiplier function is active, this
ensures that the input A trigger LED flashes at the
same rate as the signal being measured and not at
the multiplied rate of the frequency multiplier output.
10. RESET (CCT. DIAG. 5)
The RESET circuitry enables the user to set the
display to zero and prepare the counter for the next
measurement. Two user resets are provided, ( 1) the
front panel pushbutton and, (2) the rear panel input
sockets. The front panel reset is performed by
S1003. When this button is pressed, pin 19 of IC205
is pulled low , this resets the main counter. Note the
reset signal is also sent to other parts of the counter
circuit to perform various necessary resets.
When the rear panel reset input is pulled low TR206
is turned off allowing TR205 to turn on which pulls
the reset line low to perform a reset. When the reset
signal is removed TR206 is turned on via R207 and
R213 which allows the reset line to return high.

Protection up to ± 20V is provided by D201, D203 an
D204, with the input current limited by R207.
An internal reset is generated by the front panel
switch logic, this resets the counter whenever a
range of function change is made.
11. DISPLAY HOLD (CCT. DIAG. 5)
The display hold "freezes" the last measurement
made on the display. Two separate functions are
available ( 1) a variable display hold and (2) an indefi-
nite display hold. The variable hold is performed by
the monostable IC201. After the main IC has per-
formed and displayed the result of a measurement,
the STORE output of IC205 goes low and triggers the
mon,ostable. The Q output of IC201 passes via the
NOR gate IC206 and sets the following RS latch
IC206(a,b) output high, this causes IC205 to "freeze"
the display. At the end of the monostable timing
period the RS latch is reset and the counter makes
the next measurement. RV1000 and C206 adjust the
HOLD time between nominaly200ms and 10s.
When the front panel HOLD button is pressed the RS
latch output is set high and thedisplay is held indefi-
nitely. When the single measure button is depressed
the monostable output sets the RS output high and
causes IC205 to "freeze" the display until the counter
is reset.
12. MAIN COUNTER IC (CCT. DIAG. 5)
IC205 is a fully integrated universal counter and dis-
play driver. It contains all the circuitry necessary to
function as a frequency counter, a unit counter, a
frequency ratio counter and a time interval counter.
The FUNCTION, RANGE, CONTROL and EXTER-
NAL DECIMAL POINT inputs are time multiplexed to
select the desired input function. This is done by
connecting the appropriate digit strobe (01 to D8) to
the control inputs. The control of these inputs is
achieved by the function, range and external decimal
point multiplexers (see CCT. DIAG. 8), which are in
turn controlled by the various control and logic cir-
cuitryand front panel switches.
A display test facility is provided, which is activated
by connecting together pins 1 and 2 of PL202. PL202
is situated on the main p.c.b. The display test illumi-
nates all the display segments and all decimal points
except decimal point8.
13. FRONT PANEL SWITCH LOGIC ,(CCT. DIAG. 7)
Resistors R701 to R703 and capacitors C701 to 703 in
conjunction with IC708(a,b,c) ensure that the set up
times of the following J-K flip flops are met. IC701
and IC702 are clocked by the (SLO CLK) and produce
a single pulse of 1ms duration each time FUNCTION,
FREQ or GATE buttons are pressed. Diodes D701,
D702, D703 and TR700 form a three input NOR gate
which generates a reset whenever the FUNCTION,
RANGE or GATE button is pressed. The next stage
of the circuit is the Programmable Array Logic (PAL).
IC703. This IC is a fusible link AND - OR gate array,
and is used to perform the complex logic functions
necessary to decode the FUNCTION, RANGE and
GATE switches. The advantage of using this device
is that it replaces many discreet IC's and therefore
allows a more compact design.
The function of IC703 can be divided into three
sections ( 1) the FUNCTION logic, (2) the RANGE
logic and (3) the GATE logic.
The FUNCTION outputs 014, 013, 012 of IC703 is a
3 bit binary code which increments by one each time
the FUNCTION button is pressed. IC704 is a 3 to 8
line decoder which decodes the PAL outputs to
provide the seven function control lines: (*FREQ),
(*RATIO), (*TIME INT), (*COUNT), (*RPM),
(*STOPWATCH) and (*PERIOD).
The RANGE outputs 019, 018, 017 are decoded by
IC705 to give the five frequency range control lines:
(*10M), (*100M), (*10kHz), (PSC) and (*100kHz).
The GATE outputs 015 and 016 are decoded by
IC706 to provide the four GATE control lines:
(*1SEC), (*10SEC), (*100ms) and (*10ms).
Note that when either the stopwatch or count func-
tions are selected the control lines from IC706 are
inhibited by the (*STOPW+COUNT) control line.
The PAL has its own "power up reset" circuit R705,
C700 and D700. This ensures that when the counter
is first switched on the RANGE is set to 10MHz, the
GATE is set to 1sec and the FUNCTION set to FRE-
QUENCY.
IC707 provides the correct decimal point positioning
for all possible combinations of selected function
range and gate time. IC707 is a fusible link ROM
(read only memory) with its address lines connected
to the PAL outputs. The ROM data lines are the deci-
mal point control signals (DPC), (DPD), (DPC).
14. RANDOM LOGIC and DISPLAY MULTIPLEXERS
(CCT. DIAG. 8)
The random logic circuitry generates various control
signals from the 1 of 8 decoders IC704, IC705, IC706.
One example is the (*FM INH) signal which is used to
enable the frequency multiplier circuit when either
the 10kHz or 100kHz frequency range is selected.
As described in section 12 the FUNCTION and
RANGE selection is accomplished by connecting the
appropriate digit drive to the control inputs of the
main counter IC. IC804 and IC805 perform this
function.
IC804 and IC805 are 8 channel analog multiplexers
which form digitally controlled single pole 8-way
switches which are controlled by the switch function
logic control signals.
See over for table showing the functions selected by
each digit for the control input.
7

FUNCTION
Frequency
Period
Function Frequency Ratio
Pin 4 Time Interval
Unit Counter
Oscillator Frequency
0.01 Sec/ 1 Cycle
Range Input 0.1 Sec/10 Cycles
Pin 21 1 Sec/ 100 Cycles
10 Sec/1k Cycles
Pin 31 Enable External Range
Input
Display Off
Display Test
Control Input 1MHz Select
Pin 1 External Oscillator Enable
External Decimal Point
Enable
DIGIT
D1
D8
D2
D5
D4
D3
D1
D2
D3
D4
D5
D4 and Hold
D8
D2
D1
D3
External Decimal point output is for same digit
Decimal Point that is connected to this input
Input, Pin 20
15. SYSTEM CLOCK and R.P.M. PRE-SCALER
(CCT. DIAG. 6)
In the standard model the 10MHz system clock is
provided by the crystal oscillator circuit XTAL 400,
C400, C401, C402 and R407. Frequency adjustment
is provided by trimmer capacitor C401.
The clock signal for IC205 is not provided directly by
the on chip oscillator but via the EXT OSC IN, this
allows for the provision of a T.C.X. O. (Temperature
Compensated Crystal Oscillator) or an externally con-
nected oscillator via the rear panel B.N.C. connector.
The gate arrangement IC401 (a,b, c) selects either the
BUFF OSC OUT signal via IC401(d) OR the externally
applied oscillator signal EXT OSC IN. The output
from pin 6 of IC401 is pre-scaled by the divide by six
counter IC402 to give a frequency of 1.6667MHz
necessary for the RPM function. IC403 selects either
the 10MHz signal from pin 6 of IC401 or the pre-
scaled output of IC402 which provides the clock
inputfor IC205.
The 10MHz output from IC401 pin 3 is buffered by
IC400 which then drives the switching transistor
TR401. The 4 gates in IC400 are connected in parallel
to ensure that there is adequate drive for TR401 . To
set the rear panel B.N.C. socket to an output the rear
panel INT/EXT switch is set to the INT position, this
turns on the current mirror formed by TR402 and
TR400 which provides collector current for TR401.
To set the B.N. C. socket to an input the switch is set
to the EXT position, this turns off TR401 by pulling
the collector of TR402 high via R403 and R410. Gate
IC401 (a) is closed and Gate IC401 (c) is opened allow-
ing an externally applied signal to be routed to the
main counter IC .
8
MIP output; this output from the main counter IC205
is used to drive the front panel GATE LED and indi-
cates that a measurement is in progress.
When using the STOPWATCH or COUNT mode or if
the input signal is gated by input B then the (GATE)
signal controls the GATE LED which then illuminates
when counting or timing is in progress. IC207(b,c)
and associated components form a pulse stretching
circuit that ensures that the GATE LED is visible even
when the measurement cycle is short.
16 . FRONT PANEL DISPLAY SECTION (CCT. DIAG. 9)
IC's 600 , 601, 602 and 603 provide buffering for the
various control signals to drive the front panel LED's.
TR600 and TR601 drive the overflow LED.
17. CONVERTING FROM 220/240V to 110/120V
OPERATION
IMPORTANT -Disconnect Mains Lead
Referring to DISMANTLING Section 3, page 2, disas-
semble up to Section 3(d).
Referring to MECHANICAL ASSEMBLY DIAGRAM,
page 3:
1. On transformer primary terminals, remove 0V to
120V link.
2. Using 16/0.1 insulated wire, connect the two 0V
terminals together, and connect the two 120V
terminals together.
3. Replace 250mA anti-surge fuse with 315mA
anti-surge fuse (and replace spare).
4. Fit label to back panel indicating voltage and
fuse type.

CALIBRATION
1. In order to calibrate the APOLLO series of counter
timers it is first necessary to dismantle the case (see
Introduction p. 2).
2. POWER SUPPLY
The first step in calibrating the instrument is to
ensure that the + 5V2 supply is set to within its
design limits of ±0.05V. If adjustment is required,
use a digital voltmeter and adjust RV100 until the
supply is within the required limits.
3. TRIGGER LEVEL calibration (see diagram p. 3)
(a) Centre both TRIGGER LEVEL controls as
accurately as possible.
(b) Set both ATTENUATION switches to x1 .
(c) Set both COUPLING switches to A.C.
(d) Carefully adjust R1219 until both input A trigger
LED's are illuminated.
(e) Carefully adjust R1269 until both input B trigger
level LED's are illuminated.
4. CRYSTAL CLOCK calibration (standard model)
Calibration of the crystal oscillator becomes
necessary is crystal drift exceeds requirements.
(a) Switch on the instrument and allow at least a
30 minute warm up period before proceeding.
(b) Set INPUT A COUPLING to AC.
(c) Set INPUT A ATTENUATION to x1.
(cl Set FUNCTION to FREQ.
(e) Set GATE time to 1s.
If) Set RANGE to 10MHz.
(g) Connect a frequency standard of known
accuracy (0.1ppm or better) to INPUT A.
Typically a 10MHz off-air standard would be
used.
(hi Adjust TRIGGER LEVEL control until a stable
reading is displayed.
(i) Adjust C401 for a reading of 10,000000 ± 5
digits.
5. T.C.X.O. calibration
(a) Proceed as section 3 steps (a) to (f).
(b) Connect a frequency standard of known
accuracy (0.05ppm or better) to INPUT A.
Typically a 10MHz off-air standard would be
used.
(cl Adjust a TRIGGER LEVEL control until a stable
reading is displayed.
(d) Adjust T.X.C.O. for a reading of 10.000000 ± 2
digits.
9

TROUBLE SHOOTING AND FAULT
FINDING
GENERAL
Check all control settings before assuming the instru-
ment is fa:..ilty. In particular the position of the
SINGLE MEASURE, HOLD, HOLD OFF, LPF, TRIG-
GER LEVEL, and rear panel INT OUT /EXT IN con-
trols.
Check that the correct fuse is fitted: 20mm 250mA
anti-surge. NO OTHER TYPE SHOULD BE USED.
When replacing components always use a part of the
specified type and tolerance. This is not just a matter
of accuracy, but often a specified component will
have improved stability and thermal performance
compared to superficially similar items. It is particu-
larly important that transistors are replaced with the
specified item otherwise performance may be
degraded.
It is always advisable to re-calibrate the instrument
after servicing to ensure that the performance is
within specification.
POWER SUPPLIES
A faulty power supply can cause a variety of faults.
Use test points TP100, TP101 and TP102 to check
the supply voltages. It is particularly important that
the 5V2 supply is set to 5V ±0.05V.
PRE-AMPLIFIERS
The pre-amplifiers do not normally cause problems.
If however any components associated with the dif-
ferential amplifiers are changed then re-calibration of
the trigger level controls is essential.
OSCILLATOR
If the crystal oscillator fails this is immediately
apparent as only one digit lights up with very high
intensity. The oscillator should be monitored with an
oscilloscope at pin 38 of the main counter IC205. If
no 10MHz signal is present then suspect the crystal
XTAL400, (orT.C.X.O. if fitted).
DISPLAY
The display digit strobes are used for control of the
counter's functions and leakage between the very
fine tracks can cause a variety of function and display
problems, including "ghosting of display segments".
EXTERNALREFOSCINPUT
This input is TTL compatible, ensure that signal
source used has a compatible output level. Check
that frequency of reference signal is within the range
100kHz to 10MHz. The calibration frequency is
10MHz, if other frequences are used then the measure-
ment cycle time will increase accordingly and the dis-
play multiplexing rate will decrease.
10
SWITCH CONTROL LOGIC
A lack of response to the function, range and gate
switches is indicative of a fault in the switch control
logic, this is most commonly caused by IC703 (PAL),
or a failure of the (SLO CLK) signal. Check that the
'Q' outputs of IC703 respond to the function, range
and gate switches and for the presence of the clock
signal at pin 1 of IC703.

PARTS LIST
CIRCUIT DESCRIPTION PART No. CIRCUIT DESCRIPTION PART No.
POSITION POSITION
Semiconductors 01203-01205 BC184 22-005
IC100
LM 340T - 5 (7805CT) 24-036 01206-01209 BF199 22-003
IC101
LM 317T 24-038 01210 BC184 22-005
IC102
LM 320LZ - 5 (79L05 ACP) 24-037 01211-01212 2N3906 22-006
y IC200 74HC 86N 24-030 01213 MPS2369 22-008
IC201
7556 IPD 24-040 01250 BF256A 22-019
IC202 74HC 27N 24-019 01251-01255 BF240 22-004
IC203 74HC 175N 24-024 01256-01259 BF199 22-003
IC204 74HC 04N 24-016 01260-01262 BC184 22-005
IC205 ICM 7226 BIPL 24-012 01263 MPS2369 (PN2369, 2N2369) 22-008
IC206 74HC 10N 24-018 D100 S005 23-008
IC207 74HC 02N 24-028
D201
BZY88 C4V7 23-007
IC208 -IC209 74HCTOON
24-029 D202 -D204 IN4148 23-005
IC304 74HC 151N 24-031 D206 -D208 IN4148 23-005
IC305 74HC 02N 24-028 D402 IN4148 23-005
IC306 74HC 107N 24-022 D600 -D628 Lamp L.E.D. T.1 26-001
IC307 -IC309 74HC 390N 24-027 D700 -D703 IN4148 23-005
IC400 74LS 37N 24-020 D1101-D1103 IN4148 23-005
IC401 74HCT
OON
24-029 D1200-D1201 IN906 23-004
IC402 74LS 92N 24-021 D1202-D1205 IN4148 23-005
IC403 74HCT
OON
24-029 D1250-D1251 IN916 23-004
IC600 -IC603 74LS 365N 24-025 D1252-D1255 IN4148 23-005
IC604 74LS 366N 24-026
DSY1-DSY8
Display L.E.D. 0.5"
26-002
IC700 -IC702 74HC 107N 24-022 Crystal
IC703
PAL 16R8 24-041
XTAL 400 Crystal 10MHz 25-001
IC704 -IC706 74HC 138N 24-023 Inductors
IC707 N82S129 (AM27S21PC) 24-042 L1200-L1201
Inductor 1uH 17-001
IC708 74HC 14N 24-015
ICBOO -IC801 74HC 08N 124-017 Capacitors
IC802 74HC 04N 24-016 C102 Electrolytic 470uF 25V 20-044
IC803 -IC805 4051 B 24-035 C103 Ceramic 100nF 63V 20-013
IC1101 LM339 24-039 C104 Electrolytic 100uF 25V 20-005
IC1102 4046B 24-033 C105 Ceramic 100nF 63V 20-013
IC1103 4518B 24-034 C106 Electrolytic 10uF 16V 20-018
IC1104 4011B 24-032 C107 Ceramic 100nF 50V 20-013
IC1105 SP8647B DG 24-014 C108 Electrolytic 100uF 25V 20-005
IC1106 74HC 14N 24-015 C109 -C125 Ceramic 100nF 50V 20-013
IC1200 MC10116P 24-013 C200 Tantalum 0.47uF 35V 20-039
C201
Ceramic 39pF 100V 20-009
TR205-TR206 BC 184 22-005 C202 Ceramic 100nF 50V 20-013
TR400 2N3906 22-006 C203 Electrolytic 10uF 16V 20-018
TR401 MPS2369 (PN2369, 2N2369) 22-008 C204 Ceramic 100nF 50V 20-013
TR402 2N3906 22-006 C205 Electrolytic 100uF 6V3
20-011
TR600 BC212A 22-001 C206 Tantalum 10uF 16V 20-041
TR601 BC184 22-005 C207 Ceramic 100nF 50V 20-013
TR700 BC184 22-005 C210 -C212 Ceramic 100nF 50V 20-013
TR1101 BC212A 22-001 C213 Ceramic 1nF 100V 20-048
TR1102 BC184 22-005 C305 Ceramic 100nF 50V 20-013
01200
BF256A 22-019 C400 Ceramic 39pF 100V 20-009
01201-01202
BF240 22-004
C401
Ceramic 56pF 63V 20-067
C402
Trimmer
2-22pF 21-003
11

CIRCUIT DESCRIPTION PART No. CIRCUIT DESCRIPTION PART No.
POSITION POSITION
Capacitors R216
CF W33 100K 18-037
C403 -C405 Ceramic 100nF 50V 20-013 R217-R220 CF
W33 10K 18-029
C406
Tantalum
1uF 35V 20-038 R300-R304 CF
W33
10K 18-029
C407 Ceramic 68pF 100V 20-037 R305
CF W33
4K7 18-027
C408 Polyester 22nF 63V 20-043 R307 CF
W33
10K 18-029
C600 -C605 Ceramic 100nF 50V 20-013 R400 CF
W33 100K
18 -037
C606 Electrolytic 100uF 6V3 20-011
R401
CF W33
4K7 18-027
C700
Tantalum
1uF 35V 20-038 R402 CF
W33 1K 18-020
C701 -C703 Ceramic 100nF 50V 20-013 R403-R404
CF
W33
4K7 18-027
C704 Polyester 22nF 63V 20-043 R407 cc
W25
22M 18-001
C1101 Ceramic 27pF 100V 20-049 R408 CF
W33
22R 18-074
C1102
Tantalum 2u2 16V 20-040 R409
CF
W33 27R 18-075
C1103
Tantalum 10uF 16V 20-041 R410
CF
W33 270R 18-014
C1104-C1109 Ceramic 100nF 50V 20-013
R411 CF
W33
22R 18-074
C1200 Ceramic 220nF 100V 20-042 R412 CF
W33
680R 18-018
C1201 Ceramic 6n8 500V 20-035 R413
CF W33
1K2 18-021
C1202 Ceramic 18pF 500V 20-047 R414-R415
CF W33
10K 18-029
C1203 Ceramic 150pF 100V 20-046 R416
CF W33
1M2
18-077
C1204 Ceramic 47pF 500V 20-006 R600-R606 CF
W33
270R 18-014
C1205 Ceramic 4n7 63V 20-036 R607
CF W33
10R
18-008
C1206 Ceramic 100nF 50V 20-013 R608-R609 CF
W33
270R 18-014
C1207-C1208 Ceramic 10nF 63V 20-008 R610
CF
W33
4K7
18 -027
C1210 Ceramic 100nF 50V 20-013
R611 CF W33
1K 18-020
C1211 Electrolytic 100uF 6V3 20-011 R612 CF
W33
4K7 18-027
C1212 Ceramic 100nF 50V 20-013 R613-R614 CF
W33
270R 18-014
C1213 Electrolytic 100uF 6V3 20-011 R700-R703
CF
W33
4K7 18-027
C1214 Ceramic 100nF 50V 20-013 R704-R705
CF W33
10K 18-029
C1216-C1217 Ceramic 100nF 50V 20-013 R706 CF
W33
4K7 18-027
C1218 Electrolytic 100uF 6V3 20-011 R707 CF
W33
47K 18-031
C1250 Ceramic 220nF 100V 20-042 R1000-R1001 CF
W33
10K 18-029
C1251 Ceramic 6n8 500V 20-035
R1101
CF W33 3K3 18-063
C1252 Ceramic 18pF 500V 20-047 R1102 CF
W33 1K8 18-023
C1253 Ceramic 150pF 100V 20-046 R1103 CF
W33
10K 18-029
C1254 Ceramic 47pF 500V 20-006 R1104-R1105 CF
W33
22K 18-030
C1255 Ceramic 4n7 63V 20-036 R1106 CF
W33 4K7 18-027
C1256 Ceramic 100nF 63V 20-013 R1107 CF
W33
1M2
18-077
C1257-C1258 Ceramic 10nF
63V 20-008 1 R1108 CF
W33 22K 18-030
C1260 Ceramic 100nF 50V 20-013 R1109 CF
W33
10K 18-029
C1261 Electrolytic 100uF
6V3
20-011 I
Rl 110 CF
W33
5k6 18-078
C1262 Ceramic 100nF 50V
20-Cf13
R1111
CF W33
470R 18-016
R1112 CF
W33
6K8
18-076
Resistors, Fixed R1113
CF W33
22K
18-030
R100 CF W33
270R 18-014 R1114 CF
W33 10K 18-029
R102 CF
W33 1K 18-020 R1115
CF W33
10K 18-029
R200-R201 CF W33
4K7 18-027 R1116 cc
W25
22M 18-001
R202-R206 CF W33
10K 18-029 R1200
MF
1W
51R 18-083
R207
CF W33
470R 18-016
R1201
CF W25
1M 250V 18-081
R208-R212 CF W33 10K 18-029 R1202
CF W25
910K 250V 18-080
R213
CF W33 1K 18-020 R1203 CF
W33
100K 18-037
R214 CF W33
4K7 18-027 R1204 cc
1W
100K 250V 18-002
R215 CF W33
10K 18-029 R1205 CF
W33
680R 18-018
12

CIRCUIT DESCRIPTION PART No. CIRCUIT DESCRIPTION PART No.
POSITION POSITION
Resistors, Fixed R1275
CF W33
330R
18-015
R1206
CF W33
330R
18-015
R1276
CF
W33
470R
18-016
R1207
CF
W33
680R
18-018
R1277
CF W33
1K8
18-023
R1208
CF W33
1K
18 - 020
R1278
CF
W33
820R
18-019
R1209
CF
· W33 330R
18 - 015
R1279
CF W33
10K
18-029
R1210
CF
W33
560R
18-017
R1280
CF
W33
1K
18-020
R1211
CF W33
680R
18-018
R1281
CF W33
10R
18-008
R1212
CF W33
100R
18-012
R1289
MF W5
82R
18-087
R1213-R1214 CF W33
680R
18-018
RB800
Block SIL 8 x 4K7
18-082
R1215-R1216 CF W33
82R
18-038
Resistors, Variable
R1217
CF W33 15K
18-036
R1220
CF
W33
12K
18-065
R101
Open preset Hor. W2 100R
19-004
R1221
CF W33
10K
18-029
R1218
Variable Pot. linear 2K
19-001
R1222
CF W33
4K7
18-027
R1219
Open preset Vert W2 4K7
19-011
R1223
CF W33
330R
18 - 015
R1268
Variable Pot. linear 2K
19-001
R1224
CF W33
470R
. 18 - 016
R1269
Open preset Vert W2 4K7
19-011
R1225
CF W33
330R
18-015
RV1000-
R1226
CF W33
470R
18-016
RV1001
Variable Pot. linear 1M
19-003
R1227
CF
W33
1K8
18-023
Switches
R1228
CF W33
820R
18 - 019
S400
Slide 2P2W
16-001
R1229
CF W33
10K
18-029
S1001-S1002
Slide 2W2W
16-006
R1230
CF W33
1K
18-020 S1003-S1010
Push 8 position
16-009
R1231
CF W33
10R
18-008
S1008-S1010
Push 3 position
16-010
R1232
CF W33
100R
18-012
S1200
Slide 2P4W
16-007
R1233
CF W33
180R
18 - 062
S1201
Slide 2P2W
16-006
R1234
CF W33
1K
18-020
S1250
Slide 2P4W
16-007
R1235
CF W33
180R
18-062
S1251
Slide 2P2W
16-006
R1236
CF W33
1K
18-020
SW100 Mains,
on/off rocker
16-011
R1237-R1238 CF W33
2K2
18-024
Sockets/Connectors/Pins
R1239
MF W5
82R
18-087
SK100
Socket housing 4 way
14-029
R1250 MF 1W
51R
18-083
SK101
Socket housing 6 way
14-031
R1251 CF
W25 1M
250V
18-081
SK102
Socket mains I.E.C.
14-017
R1252
CF W25
910K
250V
18-080
SK401
Socket housing 8 way
14-033
R1253
CF W33
100K
18-037
SK200
Socket 4mm red
14-023
R1254 cc 1W
100K
250V 18-002
SK200
Socket 4mm black
14-022
R1255
CF W33
680R
18-018
SK400
Socket BNC 50 Ohm
14-002
R1256
CF W33
330R
18-015
SK600-SK603 Socket P.C.B.
14-025
R1257 CF W33
680R
18-018
SK1200
Socket BNC 50 Ohm
14-002
R1258
CF W33
1K
18-020
SK1201a
Socket P.C.B.
14-026
R1259
CF W33
330R
18-015
SK1201b
Socket P.C.B.
14-027
R1260
CF W33
560R
18-017
SK1202
Socket P.C.B.
14-014
R1261
CF
W33
680R
18-018
SK1203
Socket P.C.B.
14-026
R1262 CF W33
100R
18-012
SK1250
Socket BNC 50 Ohm
14-002
R1263 - R1264 CF
W33
680R
18-018
TP100-TP103
Test pins
14-005
R1265 - R1266 CF W33
82R
18-038
PL100
Plug 4 way
14-028
R1267 CF W33
15K
18-036
PL101
Plug 6 way
14-030
R1270
CF W33
12K
18-085
PL401
Plug 8 way
14-032
R1271 CF W33
10K
18-029
R1272 CF W33
4K7
18-027
R1273 CF W33
330R
18-015
R1274 CF W33
470R
18-016
13

DESCRIPTION
Miscellaneous
Socket I.C. 40 pin O.1.L. (3)
Socket I.C. 20 pin O.1.L.
Socket I.C. 16 pin O.1.L.
Socket I.C. 14 pin O.1.L.
Spacer P.V.C. (L.E.O.) (29)
Tag, Solder (B.N.C.) (3)
Sleever, Rubber H15 (13)
Shroud, mains
Pin, P.C.B. (8)
Pin, P.C.B. (62)
Fuse , 20mm 250mA anti-surge (2)
P.C.B. (main)
P.C.B. (Front panel)
P.C.B. (Pre-amp)
P.C. B. (Switch)
Front panel printed (Apollo 10)
Front panel printed (Apollo 100)
Case upper (inserts)
Case lower (drilled)
Expansion strip (2)
Foot A (2)
Foot B (2)
Leg
Screw M3 x 70 (4)
Pad, foot (4)
Rear Panel, printed
Knob, grey (4)
Knob cap blue (4)
Knob cap green (2)
Stand-off washer B.N.C. (2)
Insulator B.N. C. (2)
Button, grey (8)
Washer, Mic (2)
Screw 6BA x ½" Pozi PN HO (2)
Nut 6BA (2)
Washer 6BA (2)
Washer, shakeproof M3 (5)
Insulator, top hat T0220 (2)
Screw M3 x 12 Tamper proof
Screw M3 x 10 Pozi C/S (2)
Screw No. 4 x ¼" Pozi (4)
Nut M3 (3)
Screw M4 x 12 Pozi PN HO (27
Screw M4 x 12 Pozi PN HO (2)
Nut M4 (2)
Solder tag 5BA (2)
Screw M2.5 x 0.45 x 5 Pozi PN HO (2)
M4 Shakeproof washer (2)
Poly bag 12" x 16"
Poly bag 7" x 9" (2)
14
PART No.
14-013
14-036
14-016
14-037
13-030
14-003
15-004
15-005
14-024
14-015
33-002
30-006
30-007
30-008
30-009
28 - 007
28-008
27-001
27-002
27-003
27-004
27-005
27-008
13-003
27-009
28-010
29-011
29-013
29-012
13-020
15-002
29-007
13-028
13-021
13-009
13-007
13-018
15-003
13-022
13-023
13-010
13-019
13-024
13-025
14 - 035
13-026
13-027
31-010
31-011
DESCRIPTION
Manual, instruction
Guarantee card (U.K.)
Mains lead (U.K., Euro or USA)
Polystyrene end cap (2)
Carton
Heatsink
Transformer 24VA
PART No.
31-038
31-009
As appro-
priate
31-004
31-006
38-002
40-002

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R1203, 1253 and C1203, C1253 are mounted on the reverse of the
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COMPONENT LAYOUT SUB BOARD PCB
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