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Chapter 6
General Troubleshooting
Block Diagram Description
Fast ADC
in 8560 EC-series instruments
Fast ADC is a standard feature in all 8560EC instruments.When sweep
times <30 ms are selected, the spectrum analyzer digitizes video signals
with the fast ADC circuitry on the A2 controller board. The fast ADC
uses an 8-bit flash ADC that is sampled at a 12 MHz rate. Only POS
PEAK, NEG PEAK, and SAMPLE detector modes are available with
the fast ADC; NORMAL detector mode is not available. Pre-triggering
is possible with the fast ADC.
A16 Fast ADC
(8560 E-series only)
When option 007 is installed, and sweep times <30 ms are selected, the
spectrum analyzer digitizes video signals with the A16 fast ADC. The
fast ADC uses an 8-bit flash ADC that is sampled at a 12 MHz rate.
Only POS PEAK, NEG PEAK, and SAMPLE detector modes are
available with the fast ADC; NORMAL detector mode is not available.
Pre-triggering is possible with the fast ADC.
Log Expand/Video Functions
The A3 interface assembly performs log expand and offset functions.
The log expand/log offset amplifier provides a 2 dB/div log scale. When
the main ADC is used, the 5 dB/div scale is derived by multiplying the
digitized 10 dB/div trace data by two in the CPU. When the fast ADC is
used, the 5 dB/div scale is derived by amplifying the video signal by
two. The 1 dB/div scale is derived by either multiplying the 2 dB/div
trace data by two (main ADC) or amplifying the video signal by two
(fast ADC).
The spectrum analyzer uses two types of video filters. An RC low-pass
circuit provides 300 Hz to 3 MHz video bandwidths. Video bandwidths
of 1 Hz to 100 Hz are generated using digital filtering. When a digital
filter is selected, a
D
appears along the left edge of the CRT, indicating
that something other than the normal detector mode is being used.
Digitally filtered bandwidths use a sample detector.
After filtering, the video is sent to the positive and negative peak
detectors. These detectors are designed for optimum pulse response.
The positive peak detector resets at the end of each horizontal "bucket"
(there are 601 such buckets across the screen). The negative peak
detector resets at the end of every other bucket. When reset, the output
of the peak detector equals its input.
Triggering
The HP 8560E/EC has five trigger modes: free run, single, external,
video, and line. The free run and single trigger signal comes from the 1
MHz ADC clock. The line trigger signal comes from the A6 power
supply. Video triggering originates from the video filter buffer circuit on
A3. External triggering requires either a high or low TTL logic level as
determined by the setting of the trigger polarity function. The external
Summary of Contents for 8560E
Page 17: ...16 Contents ...
Page 24: ...23 1 General Information ...
Page 49: ...48 Chapter1 General Information Sales and Service Offices ...
Page 50: ...49 2 Adjustment Procedures ...
Page 132: ...131 2a Adjustment Procedures HP 3335A Source not Available ...
Page 146: ...145 3 Assembly Replacement ...
Page 224: ...223 4 Replaceable Parts ...
Page 251: ...250 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 253: ...252 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 255: ...254 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 257: ...256 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 259: ...258 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 261: ...260 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 263: ...262 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 265: ...264 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 267: ...266 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 268: ...267 5 Major Assembly and Cable Locations ...
Page 279: ...278 Chapter5 Major Assembly and Cable Locations Introduction Figure 5 9 Front End ...
Page 281: ...280 Chapter5 Major Assembly and Cable Locations Introduction ...
Page 282: ...281 6 General Troubleshooting ...
Page 285: ...284 Chapter6 General Troubleshooting Introduction Figure 6 1 Assembly Test Points ...
Page 286: ...Chapter 6 285 General Troubleshooting Introduction Figure 6 2 Ribbon Cable Connections 1 of 3 ...
Page 287: ...286 Chapter6 General Troubleshooting Introduction Figure 6 3 Ribbon Cable Connections 2 of 3 ...
Page 290: ...Chapter 6 289 General Troubleshooting Introduction Figure 6 5 Service Cal Data Menu ...
Page 331: ...330 Chapter6 General Troubleshooting Block Diagram Description Figure 6 6 Functional Sections ...
Page 343: ...342 Chapter6 General Troubleshooting Block Diagram Description ...
Page 345: ...344 Chapter6 General Troubleshooting Block Diagram Description ...
Page 347: ...346 Chapter6 General Troubleshooting Block Diagram Description ...
Page 349: ...348 Chapter6 General Troubleshooting Block Diagram Description ...
Page 351: ...350 Chapter6 General Troubleshooting Block Diagram Description ...
Page 353: ...352 Chapter6 General Troubleshooting Block Diagram Description ...
Page 354: ...353 7 ADC Interface Section ...
Page 406: ...405 8 IF Section ...
Page 436: ...Chapter 8 435 IF Section A5 IF Assembly Figure 8 3 IF Adjust Signature ...
Page 437: ...436 Chapter8 IF Section A5 IF Assembly Figure 8 4 Detailed IF Adjust Signature 1 ...
Page 438: ...Chapter 8 437 IF Section A5 IF Assembly Figure 8 5 Detailed IF Adjust Signature 2 ...
Page 439: ...438 Chapter8 IF Section A5 IF Assembly Figure 8 6 Detailed IF Adjust Signature 3 ...
Page 440: ...Chapter 8 439 IF Section A5 IF Assembly Figure 8 7 Detailed IF Adjust Signature 4 ...
Page 441: ...440 Chapter8 IF Section A5 IF Assembly Figure 8 8 Detailed IF Adjust Signature 5 ...
Page 443: ...442 Chapter8 IF Section A5 IF Assembly Figure 8 9 Noisy Signature ...
Page 444: ...Chapter 8 443 IF Section A5 IF Assembly Figure 8 10 Noise with Correct Shape ...
Page 445: ...444 Chapter8 IF Section A5 IF Assembly Figure 8 11 Region B Amplitude Variation ...
Page 447: ...446 Chapter8 IF Section A5 IF Assembly Figure 8 13 Faulty Crystal Short ...
Page 463: ...462 Chapter8 IF Section Cal Oscillator Assembly P O A4 ...
Page 465: ...464 Chapter8 IF Section Cal Oscillator Assembly P O A4 ...
Page 467: ...466 Chapter8 IF Section Cal Oscillator Assembly P O A4 ...
Page 469: ...468 Chapter8 IF Section Cal Oscillator Assembly P O A4 ...
Page 470: ...469 9 Controller Section ...
Page 486: ...Chapter 9 485 Controller Section Display Problems 8560E Figure 9 10 Delta Y Waveform ...
Page 503: ...502 Chapter9 Controller Section Keyboard Problems ...
Page 505: ...504 Chapter9 Controller Section Keyboard Problems ...
Page 506: ...505 10 Synthesizer Section ...
Page 577: ...576 Chapter10 Synthesizer Section A21 OCXO ...
Page 579: ...578 Chapter10 Synthesizer Section A21 OCXO ...
Page 581: ...580 Chapter10 Synthesizer Section A21 OCXO ...
Page 582: ...581 11 RF Section ...
Page 598: ...Chapter 11 597 RF Section A14 Frequency Control Assembly Figure 11 2 A7 LODA Drive ...
Page 617: ...616 Chapter11 RF Section A10 Tracking Generator Option 002 ...
Page 618: ...617 12 Display Power Supply Section ...
Page 651: ...650 Chapter12 Display Power Supply Section A6 Power Supply Assembly ...
Page 653: ...652 Chapter12 Display Power Supply Section A6 Power Supply Assembly ...
Page 654: ...653 13 Component Level Information Packets ...
Page 660: ...Chapter 13 659 Component Level Information Packets Introduction ...