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 INTRODUCTION 

The  G22K511 

television receiver is designed for reception of both 

colour  and  monochrome  pictures  on  625  lines.  A  22"  rectangular 

shadow  mask  cathode  ray  tube  is  employed  around  which  are 

fitted  a  pair  of degaussing coils. These  automatically  degauss the 

tube  each  time  the  receiver  is  switched  on.  The  main  chassis  is 

mounted vertically at the rear of the receiver, and when servicing 

is  necessary,  it  can  either  be  hinged  backwards  or  removed  com-

pletely.  The  tuner  is  a  UHF/VHF  integrated  type,  operated  by 

four push-buttons which can be set to receive any 625-line channel 

on UHF or relay channel on VHF. By removing one screw, a part 

of the front escutcheon comes away, revealing easy access to the 

grey  scale  and  dynamic  convergence  controls.  This  enables  the 

more difficult setting up to be done from the front of the receiver. 

Special  features  include  a  fully  pluggable  I.F.  panel  to  facilitate  easy 

servicing,  and  a  new  black  level  clamp  circuit  to  ensure  faithful 

reproduction of low key scenes. 

The G25K512 

is a 'Deluxe' version of the above receiver employ- 

ng a  25"  push  through cathode  ray tube. Housed in  a consolette 

tyle cabinet and finished in teak veneers, it has two single doors 

which are secured by ball catches when closed. 

 

SPECIFICATION 

Mains supply 

240 

volts a.c. only 

Valves 

Type 

Function 

V1706 

A56-120X 22" Shadow-mask C.R.T. 

or V1706 

A63-120X 25" Shadow-mask C.R.T. 

V2001 

PFL200 Luminance output and sync. separator 

V2002 

EF80 

Line sync. amplifier 

V4001 

PCF802 Line reactance and oscillator 

V4002 

ECC81 

Field oscillator 

V4003 

PCC85 

Field buffer/fly-back suppression 

V4004 

PL508 

Field output 

V5001 

PL509 

Line output 

V5002 

PY500 

Boost diode 

V5003 

PD500 

Shunt stabiliser 

V5004 

GY501 

E.H.T. rectifier 

V5005 

EY51 

Focus diode 

V7001 

EF183 

1st chroma. amplifier 

V7002 

EF184 

2nd chroma. amplifier 

V7003 

PCC85 

Chroma. A.G.C./colour killer 

V7005 

PCF200 R-Y amplifier/clamp 

V7006 

PCF200 G-Y amplifier/clamp 

V7007 

PCF200 B-Y amplifier/clamp 

V7008 

EF184 

Burst amplifier 

V7009 

PCF802 Reactance/reference oscillator 

VA V7010 

PCL86 A.F. amplifier/output 

Semi- 

Type 

Function 

conductors 

T1321 

AC128 

T2140 

BF194 

T2141 

BF194 

T2142 

BF196 

T2143 

BF196 

T2144 

BC148 

T2145 

BC148 

T2146 

BC148 

T2147 

BC148 

T2624 

BF197 

T2755 

BF173 

T3401 

BF180 

T3402 

BF182 

T3403 

BF183 

T3495 

BC108 

T7011 

BF195 

T7012 

BF195 

T7013 

BF194 

T7014 

BF194 

T7015 

BC107 

X1101 

BY127 

X1102 

BY127  

X1103 

BA148 

X1104 

BA148 

X1105 

BYX10 

X1106 

BA148 

X1292 

BA148 

X1293 

BA148 

X1294 

BA148 

X2151 

0A91 

X2152 

BA154 

X2153 

0A91 

X2530 

AA119 

X2531 

AA119 

X2625 

0A90 

X2756 

0A90 

X3496 

BZY88 

X4140 

BA148 

X4141 

BA148 

X4142 

BYX10 

X7315 

0A90 

X7316 

0A85 

X7317 

0A202 

X7318 

0A95 

X7319 

BA100 

X7320 

AA119 

X7321 

AA119 

X7322 

0A91 

X7323 

BA148 

X7324 

X7325 

BA154 

X7568 

0A95 

X7569 

0A95 

X7570 

0A95 

X7571 

0A95 

X7628 

BAY38 

X7629 

BAY38 

X7630 

BAY38 

X7631 

BAY38 

X7632 

BAY38 

X7655 

0A95 

X7656 

0A95 

Circuit protectors 

Fuses 

Type 

FS1107 

3A 

FS1108 

Thermal 

FS1109 

250mA 

FS1110 

Thermal 

FS1114 

Thermal 

Drop-off resistors 

R2111 

1.5K52 

R4135 

12052 

Safety resistors 

R4083 

3.3K52 

R7148 

1052 

R7151 

1052 

R7263 

1ic52 

R7293 

18052 

Spark gaps 

SG10981 

SG1099 f 

E.H.T. 

Loudspeaker 

Sound  output 

Dimensions 

G22K511 

G25K512 

Weight 

G22K511 

G25K512 

 

li 

Convergence clamp 

1st sound I.F. 

2nd sound I.F. 

1st vision I.F. 

2nd vision I.F. 

Luminance phase splitter 

Luminance A.G.C. amplifier 

Black level clamp 

Chroma. pre-amplifier 

3rd vision I.F. 

Chrominance amplifier 

R.F. amplifier 

Mixer 

Oscillator 

A.G.C.  amplifier 

B-Y  pre-amplifier 

R-Y pre-amplifier 

}Bistable oscillator 

Identification signal amplifier 

Mains rectifier 

Mains rectifier 

L.T.  supply  rectifier  L.T. 

supply 

rectifier 

ve  supply 

rectifier  Supply  for  black 

level clamp 

}Auxiliary d.c. supply to C.R.T. 

A.G.C. delay 

Black level clamp 

A.G.C. rectifier 

F.M. ratio detector 

Luminance demodulator 

Chrominance demodulator 

Tuner supply stabilisation 

} Line discriminator 

Fly-back pulse clipper 

Chroma. noise clipper 

}Burst keying 

Burst blanking 

Bias clamp 

}PAL switch (180°) 

Identification signal gate 

Stabilised H.T. supply 

4.43 MHz crystal 

Beam current limiter 
B-Y  demodulator 
R-Y  demodulator 
Anti-lock-out 
Chroma. A.G.C. demodulator 

Burst demodulator 
Ref. oscillator A.G.C. 

Ref. oscillator grid clamp 

Location 

Mains supply 

Main H.T. supply 

Field output 

Main H.T. supply 

Mains transformer 

Luminance output 

Field output stage 

Line reactance stage 1st 

chroma. amp. stage 

2nd chroma. amp. stage 

Burst amp. stage 

A.F. output stage 

C.R.T. base panel 
25kV 

6" x 4" elliptical, 5ohm

 

impedance 2.5 watts 

Height 

Width 

Depth 

(Inc. backplate) 

28" 

2W 

31-i" 

23" 

861bs. 

1291bs. 

181' 

33f" 

(Inc. legs) 

Page Three 

Summary of Contents for G22K511

Page 1: ...VERS c es C O MMB I N E D E L E C T R O NI C S ER V I C ES LI MI TE D 604 PURLEY WAY WADDON CROYDON CR9 4DR TELEPHONES Spare part orders 01 686 3831 General service enquiries 01 688 7722 After business hours Recorded messages on both lines Telex 262308 AUGUST 1969 Please quote CES 739 when ordering further copies CES 739 ...

Page 2: ...d ILLUSTRATIONS Fig No RECEIVER IDENTIFICATION 1 SPRING RESISTOR R1073 If2 CONVERGENCE COVER 3 ASSEMBLY OF C R T AND SHIELD 4 C R T SHIELD 5 TRIM PLAN 6 THIRD HARMONIC TUNING 7 DEFLECTION ASSEMBLY 8 CONVERGENCE PANEL 9 TERMINATING PAD 10 DAMPER DETECTOR UNIT 11 DETECTOR UNIT 12 15 RESPONSE CURVES 16 BIAS NETWORK 17 X Y DISPLAYS 18 BLOCK DIAGRAM 19 CONVERGENCE ASSEMBLY WIRING 20 L O P T ASSEMBLY UP...

Page 3: ...G22K511 G25K512 Page Two ...

Page 4: ...T2144 BC148 T2145 BC148 T2146 BC148 T2147 BC148 T2624 BF197 T2755 BF173 T3401 BF180 T3402 BF182 T3403 BF183 T3495 BC108 T7011 BF195 T7012 BF195 T7013 BF194 T7014 BF194 T7015 BC107 X1101 BY127 X1102 BY127 X1103 BA148 X1104 BA148 X1105 BYX10 X1106 BA148 X1292 BA148 X1293 BA148 X1294 BA148 X2151 0A91 X2152 BA154 X2153 0A91 X2530 AA119 X2531 AA119 X2625 0A90 X2756 0A90 X3496 BZY88 X4140 BA148 X4141 BA...

Page 5: ...l trimming tool A special star shaped trimming tool is necessary for the alignment of the tuner I F coil and also for adjustment of certain other cores This trimming tool is available as part of the Philips trimming tool kit 800 TX and engineers are advised that any attempt to adjust these cores with a non standard tool may damage them 5 Use of the circuit diagram a The complete circuit of the G6 ...

Page 6: ...under the tags and not wrapped around them 2 Ballast resistors During manufacture a high melting point solder is employed on all connections to the supply ballast resistors R1052 R1053 It is most essential that this grade of solder e g Ersin Comsol Alloy is used with a high temperature soldering iron if this component is replaced 3 Thermal fuses FS1108 and FS1110 Two thermal fuses FS1108 and FS111...

Page 7: ...hdrawn from the cabinet 7 Replacement of degaussing coils L1723 4 Remove the main chassis tuner assembly control panel and con vergence unit together with the convergence yoke deflection coils and blue lateral unit Lay the cabinet face downwards supported at each corner to prevent the C R T taking the weight of the cabinet 8 Removal of the C R T WARNING Extreme care must be taken when handling the...

Page 8: ... all the tappings on the line trans former windings are available externally via the two 10 way sockets mounted on the side of the E H T can assembly and connections to many components can be made either on the printed panel or within the valve compartment of the assembly once the gauze screen has been removed In cases of arcing due to breakdown of a component inside the assembly it may be first n...

Page 9: ...2 o 0 0 0 1 0 FOCUS L L L L 2744 2746 2745 2747 PRE SET A G C c i 7 1 0 5 7 L L 72 2 3 4 2 5 2 7 8 3 L 10 0 OD 9 r gd R2092 n L L L2598 0 _____11_2596 7 2555 2554 L2564 0 L2621 L2620 L 2 5 8 6 L2773 L2775 Is F1271b 12 L 2643 4 L264 W611 R2073 A M REJECTION L2603 I 5 5 1 L 2 5 26 L2528 9 LUMINANCE FEED TO C R T CATHODE L2503 l L2504 R7285 I 1 C R T CUT OFF R1167 CONTRAST sl 75Z3 7559 60 7561 L 7 6 ...

Page 10: ... picture is correctly set up Adjust R5045 for optimum focus 10 Vertical hold control R4098 Adjust vertical hold control R4098 to obtain a correctly locked picture 11 Vertical bias control R4105 Before adjusting R4105 check that the boost voltage is correct see para 2 Connect a voltmeter across R4117 pin 7 V4004 to chassis then adjust R4105 to give a reading of 12 5 volts 12 Height control R4101 Be...

Page 11: ... each control Degaussing The receiver is fitted with an automatic degaussing circuit which operates each time the set is switched on from cold However in cases where the C R T and or associated metal parts have been subjected to extra strong magnetic fields it may be necessary to pass an external degaussing coil across the C R T face and in each corner before purity convergence adjustments are car...

Page 12: ...Page Ten ...

Page 13: ...n The solder tags on L1523 are at H T potential 4 Converge the horizontal lines at the bottom of the screen with control 3 and the horizontal lines at the top of the screen with control 4 5 With controls 7 and 8 converge the left and right hand vertical lines 6 Check static convergence and readjust if necessary 7 Switch on the blue gun depress button 17 again 8 Adjust controls 10 11 and 12 to make...

Page 14: ...Page Eleven ...

Page 15: ... warm up period of at least 20 minutes should be allowed for thermal stabi lisation of both receiver and test equipment Leads should be as short as practicable in order to have least effect on the response curve When the sweep generator is connected to the various injection points stated the terminating pad shown in Fig 9 should be used The adjustment of certain vision I F coils will affect both l...

Page 16: ...om X7326 and pins 4 and 5 of V7008 then check the adjustment of R7179 and R7206 see section H paras 22 and 23 Note When alignment of the chroma bandpass circuit has been completed the decoder alignment must be checked particularly the setting of L7559 60 and L7561 I F ALIGNMENT TABLE Inputfrom C20 4I sweep generator to and turn R2092 fully clockwise TP7 tuner injection point via the terminating pa...

Page 17: ... normal picture Connect a high impedance voltmeter from pin 2 of V7003 to chassis ve lead to chassis Adjust L7624 6 for maximum negative reading on the meter approx 4v OVERALL CHROMINANCE BANDPASS RESPONSE 503904e Fig 13 37MHz 33 5MHz RESPONSE AT COLLECTOR T2143 503904f Fig 15 4 R7618 discriminator balance Apply a colour signal to the aerial socket and set up the controls for a normal picture Conn...

Page 18: ...ips of the duplicated ellipses o 17B shows these ellipses before the adjustment is carried out 7 Adjust L7562 3 so that the diagonal ellipses especially on the magenta green axis become as thin as possible It may not be possible to make all the ellipses into thin lines with L7562 3 in which case the best compromise should be achieved 8 Synchronise the reference oscillator by removing the 1 0v sour...

Page 19: ...Page Fifteen ...

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