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Circuit Description—4 55 /A2/B2
Horizontal Preamplifier 1C
The Horizontal Preamplifier circuit is contained w ithin a
single 1C, U2900.
The following is a brief description of the function associat
ed w ith each pin of U2900.
Pin 1. Magnifier registration. This pin is used in con
junction w ith pin 8 to provide registration between the
normal and magnified sweeps.
Pin 2. Sweep. This pin provides the negative-going
sweep o utp ut to the Horizontal O utput Am plifier. This
output represents the inputs to pin 9 or 10, except in the
X-V mode when pin 12 is HI, and it represents the input
to pin 11.
Pin 3. Gain. This pin, in conjunction w ith pin 6, is con
nected to the gain setting circuitry. The X I 0 Magnifier
switch is connected to this pin.
Pin 4. —5 volt supply.
Pin 5. Current source. Sets internal current levels.
Pin 6. Gain. See pin 3.
Pin 7. + Sweep. This pin provides the positive-going
sweep output to the Horizontal O utput Am plifier.
Pin 8. Magnifier registration. See pin 1.
Pin 9. B Sweep In. Input connection fo r the B sweep
signal.
Pin 10. A Sweep In. Input connection fo r the A sweep
signal.
Pin 11. X Signal. Input connection fo r the X signal
from CH 1 when the A T IM E /D IV switch is in the X-Y
position.
Pin 12. X-Y Mode. When this pin is LO (normal sweep
mode), the outputs at pins 2 and 7 represent the inputs
to pin 9 or pin 10.
Pin 13. Frequency compensation. Connects to frequen
cy compensating capacitor.
Fig. 4-9. Sweep-circuit waveform relationships.
9
REV. A, OCT 1975
Pin 14. Horizontal position. Connects to the horizontal
POSITION control.
Summary of Contents for 455
Page 1: ...Tektronix 455 A2 B2 PORTABLE OSCILLOSCOPE WITH OPTIONS I N S T R U C T I O N M A N U A L ...
Page 9: ......
Page 13: ...455 A2 B2 x 455 A2 B2 Portable Oscilloscope ...
Page 61: ...Circuit Description 455 A2 B2 Fig 4 4 Channel switching gates REV A OCT 1975 4 9 ...
Page 66: ...Fig 4 6 Sweep generator 1C Function block diagram Circuit Description 455 A2 B2 ...
Page 80: ...Maintenance 455 A2 B2 BOTTOM FRAME Fig 5 7 VO LTS DIV switch disassembly 5 8 REV A OCT 1975 ...
Page 90: ...Maintenance 455 A2 B2 Fig 5 13 Troubleshooting chart 5 18 REV A O CT 1975 ...
Page 91: ...Maintenance 455 A2 B2 1907 1 A Fig 5 13 Troubleshooting chart cont REV A OCT 1975 5 19 ...
Page 132: ...Instrument Options 455 A2 B2 Option 7 Page 8 REV E AUG 1979 D C TO AC I NVERTER ...
Page 166: ...l 07 7 REV b NOV C M1 4 5 5 MAIN MODULE BLOCK DIAGRAM ...
Page 167: ...4 5 5 A 2 B 2 AS VERTICAL MODULE IR07 R8 RE V B M O ...
Page 168: ...I S 0 7 9 8 R E V B NOV IRT7 A2 VERTICAL MODULE BLOCK DIAGRAM ...
Page 169: ...REV B NOV 1977 Fig 9 2 A1 Partial Interface board compo ...
Page 170: ...455 A2 B2 Sea Parts List for serial number ranges tial Interface board component locations ...
Page 173: ...v I m B 2 HORIZONTAL MODULE BLOCK DIAGRAM ...
Page 174: ...455 A2 B2 REV B NOV 1977 Fig 9 3 A 1 Partial Interface board component locations ...
Page 182: ...455 A2 B2 Fig 9 4 A20 Vertical board component locations SN B0110 ...
Page 185: ...455 A2 S2 4 5 5 M A fN M O DULE ...
Page 187: ...455 A2 B2 Fig 9 5 A20 Vertical board component location SN B010100 B REV C NOV 1977 ...
Page 191: ...V O L T S 01 ...
Page 192: ...V O LT S Q IV S H O W N IN 57 H V ...
Page 198: ... U 1 X SlCjMAt TO P2 A4 h o p it MODULE SEE PARTS LIST FOR SEMICONDUCTOR TYPES f SWITCHING ...
Page 207: ...A 1 4 B T I M I N G S W I T C H B O A R D A13 A TIM ING SWITCH BOARD 1 9 0 7 3 ...
Page 209: ...4 5 5 A 2 B 2 B 2 h o r iz o n t a l m o d u l e R o i I 11 R E V C NOV IS77 ...
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Page 214: ......
Page 216: ...A B T IM IN G S W IT C H INTERFACE C O N N E C T O R ...
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Page 224: ...455 A 2 B 2 ...
Page 225: ... 455 A2 B2 ...
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Page 234: ...455 A2 B2 ...