UNIT DESCRIPTIONS
5.2 - 37
Diagram 4.
This diagram shows the final intensity (Z) and focusing amplifiers. These amplifiers drive the intensity
electrode G1 and the focusing electrode G3 of the CRT. The input circuit is formed by IC D3001.
Input pin 5 and 6 of D3001 receive the Z-pulses ZLTRAO and ZLTRA1 that determine the intensity
during signal display. Input pin 9 and 10 receive the Z-pulse ZTXTO and ZTXT1 that determine the
intensity during text/cursor display. The selection between signal intensity and text intensity is done
via the signals ZSWO and ZSW1 that are applied to pin 7 and 8 of D3001. These signals originate
from the text generator IC on microprocessor unit A3. Text is displayed with ZSWO at 0 mA and ZSW1
at 1 mA. Trace is displayed with ZSWO at 1 mA and ZSW1 at 0 mA.
The final Z-amplifier and the focusing amplifier are identical halves that receive input signals that are
in opposite phase. These signals originate from the D3001 outputs pin 24/25 (ZDRIF1/ZDRIF0) and
pin 18/19 (ZDRII0/ZDRII1).
Via V3002 part of the ripple on the negative CRT cathode voltage (ZRIPPLE) is applied to pin 15 of
D3001. This compensates for unwanted intensity modulation due to this ripple.
The diodes V3236, V3136, V3237 and V3137 protect D3001 against possible high voltage surges.
V3301 supplies the intensity determining signal INTEN-DA. This signal adjusts the "dark level" of the
CRT. V3301 is controlled by DAC N2002 output signal DARK. V3311 supplies signal ASTIG that
determines the astigmatism of the CRT. V3311 is controlled by DAC N2002 output signal ASTDR.
The upper amplifier half that is used for the dynamic focus control is explained now. Its function is
identical to that of the lower amplifier half that is used for intensity (Z) control. The balanced input
signals ZDRIF1 and ZDRIFO are applied to input stage V3101. ZDRIFO is not used and connected to
+6.8 V. In the collector circuit of V3101 are the zener diodes V3102/V3103 that function as level
shifters. The emitter followers V3132 and V3111 supply the output stage V3134/V3113 with signal.
V3113 functions as an amplifier stage and V3134 mainly as a current source. V3134 receives signal
via C3131 and C3134. It mainly functions as amplifier stage for fast input signals. Via R3133/R3134
however some dc drive is also applied to V3134.
Diagram 5.
In this diagram the circuit is shown that forms an interface between the signals that determine the
intensity/focusing and the CRT electrodes G1/G3 that control intensity/focusing. These electrodes,
the cathode and filament (heater) of the CRT are at a high negative voltage. This voltage is separated
from the other oscilloscope circuits via the 3kV capacitors C4004, C4061, C4036 and C4037.
The intensity is influenced by the output signal INTEN-AA of the Z- amplifier and the signal INTEN-
DA. INTEN-AA is determined via the front-panel TRACE INTENSITY, TEXT INTENSITY, MTB on,
DTB on and chopper blanking control signals. The HF component in the INTEN-AA signal is applied
to G1 of the CRT via C4037. The DC and LF components are applied to the base of V4034. The
INTEN-DA signal is applied to the base of V4032 and forms the clamplevel (dark level) of the DC and
LF part of INTEN-AA derived from V4034. These two transistors form the inputs of a 150kHz
modulator that basically consists of V4031 and V4033. The LF and DC components that are
modulated on the 150 kHz carrier signal can pass via buffer stage V4038/V4039 and then via high
voltage blocking capacitor C4036.
Behind capacitor C4036 demodulation takes place via the diodes V4043 and V4044. This results in
the original INTEN-AA signal that is superpositioned on the INTEN-DA voltage that corrects the cut
off voltage of the CRT applied to G1 and via R4051 also to G3. Across R4044 a small negative
voltage (compared with the cathode) is developed for G1. This voltage is not big enough to make the
CRT screen dark. This means that the signals to darken the screen and to control intensity are
applied via C4036 and C4037.
The HF component from the focusing amplifier output signal FOCUS-AA is applied to G3 via C4004
and voltage divider R4008/R4009/C4002/C4003. This assures optimal tracking between focus and
intensity. The signal FOCUS-DA is determined via the FOCUS control at the instruments front panel.
Summary of Contents for PM3082
Page 34: ...DESCRIPTIONS 3 1 ST8235A 970415 ...
Page 35: ...DESCRIPTIONS r _A1 SIGNAL UNIT TRIGGERING ...
Page 36: ...3 1 TIME BASES ST8235A 970415 ...
Page 37: ...3 2 DESCRIPTIONS ST82358 97041S ...
Page 38: ...XYSW ...
Page 79: ...5 1 22 UNIT DESCRIPTIONS Lay out 2 Small component side of signal unit A1 ...
Page 93: ...5 1 33 09001 2 01201 3 01201 5 C 1 O 6 0 T 10n A1 Diagram 1 Attenuator CH 1 PM3094 PM3092 ...
Page 96: ...5 1 34 UNIT DESCRIPTIONS 09001 17 A1 Diagram 2 Attenuator CH 2 PM3094 PM3092 ...
Page 99: ...5 1 35 X I STB241 970420 A1 Diagram 2a Attenuator CH 1 PM3094 PM3092 ...
Page 100: ...5 1 36 UNIT DESCRIPTIONS 12AT3 12AT3 STQ24S 970420 Diagram 3 Attenuator CH 3 PM3094 ...
Page 101: ...J a C3077 I I T b M A AT350C N1101 2AT3 12AT3 ...
Page 102: ...5 1 36 UNIT DESCRIPTIONS 12AT3 STB242 970420 Diagram 3 Attenuator CH 3 PM3094 ...
Page 104: ...5 1 37 12AT4 D4201 3 D4201 5 ST8243 97D420 Diagram 4 Attenuator CH 4 PM3094 ...
Page 105: ...UNIT DESCRIPTIONS C4071 lOn C4072 lOn AC DC f HIGH IMPEDANCE ATTENUATOR LF IMPE CONVE R40Q2 ...
Page 107: ... 12AT 12AT4 l i C4067 160u 25V C4068 10n K4002 ...
Page 109: ...I i 04097 1 0 O u 25V J 25V 10n 25V ...
Page 113: ...UNIT DESCRIPTIONS PROBE CALIBRATOR GNOR6F f 1CVREF f C11S0 180u 25V C1157 10 0n GNDREF GNDREF ...
Page 115: ...5 1 40 UNIT DESCRIPTIONS Diagram 6 Preamplifier CH 1 and CH 2 ...
Page 116: ...PAOREF N32Q2 12 ...
Page 117: ...5 1 40 UNIT DESCRIPTIONS Diagram 6 Preamplifier CH 1 and CH 2 ...
Page 118: ...UNIT DESCRIPTIONS 5 1 41 l GAIN CONTROLVAR X1 2 X5 Diagram 7 Preamplifier CH 3 and CH 4 ...
Page 119: ...UNIT DESCRIPTIONS ...
Page 120: ...5 1 41 PMVAR ft4220 Diagram 7 Preamplifier CH 3 and CH 4 ...
Page 121: ...5 1 42 UNIT DESCRIPTIONS Diagram 8 Y functions ...
Page 122: ... 12FNC12 I2R4C12 12FNC34 12FNC34 R1S13 1K47 FNC FI ...
Page 123: ...5 1 42 UNIT DESCRIPTIONS 12FNC12 FM2MV 00003 7 12FNC12 H2FNC12 Diagram 8 Y functions ...
Page 124: ...UNIT DESCRIPTIONS 10P 120LD REF VOLTAGE DG001 HEF40M I f 1 ...
Page 129: ... REF VOLTAGE j D5001 HEF4009 DS001 HEF40M If C0RHECT10N VOLT N5001 366 f ...
Page 133: ...5 1 45 D5501 HEF4053 CNT STB251 970428 Diagram 10 Display and trigger control ...
Page 138: ...5 1 47 Diagram 12 MTB trigger ...
Page 142: ...5 1 48 UNIT DESCRIPTIONS TV SYNC SEPABATOtT TV UNE FRAME SEUECTKDN Diagram 13 TV line trigger ...
Page 143: ...UNIT DESCRIPTIONS 5 1 49 160TR Diagram 14 DTB trigger ...
Page 146: ...5 1 50 UNIT DESCRIPTIONS Diagram 15 Time base logic ...
Page 148: ...5 1 50 UNIT DESCRIPTIONS V 6 0 0 4 Diagram 15 Time base logic ...
Page 149: ...UNIT DESCRIPTIONS 5 1 51 Diagram 16 Main time base ...
Page 150: ...UNIT DESCRIPTIONS R6001 ...
Page 151: ...5 1 51 ...
Page 153: ......
Page 154: ...5 1 52 UNIT DESCRIPTIONS R716Y C7181 ONLY IN PM30Q2 PM3004 Diagram 17 Delayed time base ...
Page 155: ...UNIT DESCRIPTIONS 5 1 53 X9001 I 1 D 0 O O 8 1 Diagram 18 Connectors ...
Page 214: ...UNIT DESCRIPTIONS 5 2 13 5 2 5 Circuit diagrams A2 200 MHz version ...
Page 215: ...UNIT DESCRIPTIONS 5 2 5 Circuit diagrams A2 200 MHz version 0501 22 ...
Page 216: ...5 2 13 ...
Page 217: ...5 2 14 UNIT DESCRIPTIONS A2 200 MHz Diagram 2 Final Y output stage ...
Page 218: ......
Page 219: ...5 2 14 UNIT DESCRIPTIONS STB263 970428 A2 200 MHz Diagram 2 Final Y output stage ...
Page 223: ...5 2 16 UNIT DESCRIPTIONS AC20mV DC 10V AC 80mV OCMOV A2 200 MHz Diagram 4 Final Z amplifier ...
Page 224: ...AC 60mV DC 1CV R3311 511E M20Q2 11 AST03 R3313 1 2KB7 V3311 ...
Page 226: ...UNIT DESCRIPTIONS 5 2 17 A2 200 MHz Diagram 5 Modulator demodulator and focus control ...
Page 227: ...UNIT DESCRIPTIONS FOCUS L i X2401 ...
Page 228: ...5 2 17 A2 200 MHz Diagram 5 Modulator demodulator and focus control ...
Page 231: ...8 5 ii 8 HI I Hl H s HI I i HI I ...
Page 232: ...g I S 5 S I 1 H H r lr H J g if j r r 8 3 8 8 S 3 5 5 H H 5 3 r l r l H H n ft 3 S 5 8 a s 5 ...
Page 268: ...UNIT DESCRIPTIONS 5 2 11 Circuit diagrams A2 100 MHz version ...
Page 269: ...5 2 47 ...
Page 270: ...5 2 48 UNIT DESCRIPTIONS TO CflT ...
Page 271: ......
Page 280: ...UNIT DESCRIPTIONS X2411 ...
Page 281: ...5 2 51 FOCUS LEVELSHIFTER A2 100 MHz Diagram 5a Modulator demodulator and focus control ...
Page 284: ... ...
Page 285: ...a 5 a I H rI 3 H H H 8 K fc 5 3 3 I I ...
Page 308: ...t 0 0 0 0 0 0 0 0 0 3 sS cn 03 03 UNIT DESCRIPTIONS ...
Page 310: ...R1102 R1101 R1679 R1672 R1071 R1104 B1674 u HI 406 H i402 D1402 O N j oo O O ai 5 3 ...
Page 311: ...bc646c Up BC866C 3Lp ...
Page 313: ......
Page 317: ...UNIT DESCRIPTIONS 5 3 9 5 3 5 Circuit diagrams Diagram 1 Central processor unit ...
Page 318: ...UNIT DESCRIPTIONS 5 3 5 Circuit diagrams ...
Page 319: ...5 3 9 r i Diagram 1 Central processor unit ...
Page 324: ...UNIT DESCRIPTIONS ...
Page 325: ...5 3 11 Cl 968 T 1 0 0 n C1963 I80u Diagram 3 Potentiometer DAC and lEEE option h i m ...
Page 326: ...5 3 12 UNIT DESCRIPTIONS G4 oi TEXT CURSOR CONTBOL 12MG Diagram 4 Text and cursor circuit i ...
Page 328: ...5 3 12 UNIT DESCRIPTIONS G4401 12MG TEXT CURSOR CONTROL Diagram 4 Text and cursor circuit ...
Page 342: ...UNIT DESCRIPTIONS 5 4 4 Unit lay outs TO X5201 ON CRT CONTROL A5 I O C O I D C G C I ...
Page 344: ...UNIT DESCRIPTIONS 5 4 4 Unit lay outs TO X5201 ON CRT CONTROL A5 H cc c c IH ...
Page 360: ...sna iu o UNIT DESCRIPTIONS 5 5 3 5 5 3 Circiuit diagram X5201 A5 Diagraml CRT controls unit ...
Page 367: ...UNIT DESCRIPTIONS 5 6 3 Unit lay outs TO X2401 ON ...
Page 369: ......
Page 371: ......
Page 372: ... 00 o o O o ...
Page 377: ...UNIT DESCRIPTIONS 5 6 5 Circuit diagrams G LI 001 fKfcjH ...
Page 379: ...5 6 10 t ...
Page 381: ... EHT CONVERT ...
Page 383: ...UNIT DESCRIPTIONS OUTPUTCIRCUIT V1271 BYV29 T1001 T1001 T1001 now T1001 T1001 now now ...
Page 394: ...UNIT DESCRIPTIONS 5 7 1 5 7 RESERVED FOR FUTURE EXTENSIONS ...
Page 395: ...UNIT DESCRIPTIONS 5 8 1 5 8 RESERVED FOR FUTURE EXTENSIONS ...
Page 396: ...UNIT DESCRIPTIONS 5 9 1 5 9 RESERVED FOR FUTURE EXTENSIONS ...
Page 397: ...UNIT DESCRIPTIONS 5 10 CONNECTOR BOARD A10 5 10 1 Unit lay out ...
Page 399: ...UNIT DESCRIPTIONS 5 10 CONNECTOR BOARD A10 5 10 1 Unit lay out 28 27 O O X IAJ 2 1 ...
Page 412: ...UNIT DESCRIPTIONS 5 11 3 Fig 1 Location of options Y out and external trigger ...
Page 413: ...UNIT DESCRIPTIONS ...
Page 414: ...5 11 3 Fig 1 Location of options Y out and external trigger ...
Page 415: ...5 11 4 UNIT DESCRIPTIONS Fig 2 Printed circuit board lay out of Y out unit ...
Page 417: ...UNIT DESCRIPTIONS 12V 12V 12V 12V X1003 YOP HX R1001 I 1 2 K 1 X1009 X1010 SCL ...