UNIT DESCRIPTIONS
5.1 -3
The signal ATCAL is applied to /33 attenuator R1008/R1009. ATCAL can supply several accurate
voltages that are used for vertical calibrations.
Impedance converter
This active stage consists of three sections with different frequency ranges. The sections partly make
use of the same components:
- The HF section for frequencies above 5 kHz. It is formed by C1021, FET V1006 and the two
emitter followers V1008 and V1009. The FETs V1004 and V1005 are used for input protection.
V1007 is a current source.
- The LF section for frequencies 30 Hz to 5 kHz. It is formed by operational amplifier N1001 (gain
2x) that receives the LF input signal via divide-by-two attenuator R1031/R1032. The capacitors
C1023 and C1025 are frequency determining components in the N1001 feedback loop. The
N1001 output signal is routed via R1034, V1006 and the emitter followers V1008 and V1009.
- The DC section for frequencies DC to 30 Hz. It is formed by operational amplifier N1001 (gain 2x)
that receives the input signal via divide-by-two attenuator R1031/R1032. Via feedback resistor
R1037 the voltage at the output of the impedance converter is compared with the input level via
the + and inputs of N1001. This keeps the DC output value of the impedance converter exactly at
the required value. This compensates for DC drift. Part of the feedback loop is V1001 that
determines the low-frequency gain. The N1001 output signal is routed via R1034, V1006 and the
emitter followers V1008 and V1009.
The low impedance attenuator is formed by R1072 and R1073. Switching is accomplished by V1012
and V1013. V1012 conducts in the /1 position and V1013 in the /2,5 position. The attenuator output
signal is an unbalanced signal. The unbalanced output signal is applied to the succeeding stage via
R1071 and via R1074.
Diagram 5
Probe indication circuit
There are four identical circuits of which the one for channel 1 is described. The resistor in the
indication ring of the probe is present between X1002 and ground potential. The resistance value is
measured by the microprocessor on unit A3.
The temperature of the 50Q termination resistors on diagram 1 is measured by NTC resistor R1011.
This resistor is placed in between the two termination resistors. If the temperature gets too high, the
+ input of N1101 becomes lower than the input. This makes output 13 of N1101 low and 0 volt is
detected by the microprocessor via the probe indication line PROBE1. This is the sign for the
microprocessor that the 50Q resistor is too hot and it is switched off.
LF square wave calibration
This circuit produces the voltages for the varicap diodes V1002. The diodes require control voltages
with opposite polarity. There are four identical circuits for the four vertical channels. The input signal
AT 1LFCAL is produced by a DAC and has the range 0 ... 10 volt. This is converted via the operational
amplifiers N1102, N1103 into two signals that range from -5 ... -15 volt (AT1LFCOR0) and +5 ... +15
volt (AT1LFCOR1) respectively.
Amplitude Calibrator
This circuit consists of 8-position multiplexer D1152 and operational amplifier N1104. It can supply 8
accurate voltages of 10V, 5V, 2V, 1V, 500mV, 200mV and 0V. They are supplied to the vertical
channels 1 ,2 ,3 and 4 for calibration voltages. The voltages are derived from a voltage divider with
precision resistors R1192 through R1197. The divider is supplied with an accurate 10 V reference
voltage. Under control of a three bit address ATCAL0 ... ATCAL2 one of the outputs of the voltage
divider is selected via D1152. This signal is routed to the vertical channels via buffer N1104.
Loop gain calibration
The output voltage range of a digital-to-analog converter (DAC) is changed via resistor network
R1112, R1113 and R1114. The output voltage is applied to V1001 that determines the low-frequency
gain in the channel 1 attenuator.
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 ...