7854: Difference between revisions

Revision as of 04:08, 9 October 2023

Tektronix 7854

400 MHz waveform-processing scope

Produced from 1980 to 1990

Manuals

7854 Manual Change Information through Jan 1991
7854 Test Points and Adjustment Locations
7854 Schematics (cleaned up)

Modifications

040-1066-00: Vertical Pickoff Amplifier Drift Improvement (1982)
045-0056-00: Firmware update 1.03 (1983)

Troubleshooting

Other Info

(All manuals in PDF format unless noted otherwise)

Manuals – Specifications – Links – Pictures

The Tektronix 7854 Waveform Processing Oscilloscope, introduced in 1980, is a 400 MHz combined analog / digital mainframe in the 7000 series that takes two vertical and two horizontal 7000-series plug-ins. In addition to a conventional analog (real time) scope, it contains an equivalent-time sampling 10-bit digitizer and a programmable waveform processor with GPIB interface. Single-shot, pretrigger acquisition is possible with the special 7B87 time base using real-time sampling. The project manager for the 7854 was Tom Rousseau. During early development, before it was given the name "7854", the product was referred to as the "Smart Scope", and the digital processing was called the "smarts".

The waveform processor can be programmed using a detachable calculator-style keyboard, using postfix operators ("reverse Polish notation" like HP calculators) that operate on entire waveforms, not just individual numbers.

Key Specifications

Bandwidth	(analog) 400 MHz
Fastest cal. sweep	500 ps/Div
Sample rate	500 kHz (stores repetitive waveforms up to 400 MHz)
Resolution	10 bit
Acquisition depth	128, 256, 512 or 1024 points
Memory capacity	2048 waveform points in up to 16 waveforms (optional expansion to 5120 points and 40 waveforms)
Single shot	events and pretrigger up to 50 µs/div ("2.5 µs/point") with the 7B87 Time Base
CRT	154-0644-05 (P31) or 154-0893-09 (P11); cathode −3 kV, anode +21 kV, distributed vertical deflection plates
Features	Signal averaging Cursor measurements Waveform parameter measurements GPIB interface (standard) Waveform calculation operators - add, multiply, square root, log, abs Internal RPN programming language (Reverse Polish Notation) Keystroke programming (up to 2000 keystrokes with option 2D) Programmable text display on screen
Options	Option 02: X-Y Phase Correction Option 03: EMC Modification Option 78: P11 Phosphor Option 2D: 4K Expanded memory storage for up to 40 waveforms and 2000 keystrokes
Power consumption	230 W
Weight	42 lbs / 19 kg

Application Notes

Application Notes Referencing 7854

Document	Title	Authors	Year	Links
AX-4382.pdf	WP1310 Waveform Processing System		1980	7854
AX-4425.pdf	WP1310 Signal Processing System		1980	7854 • 4052 • WP1310
AX-4440.pdf	7854 On-board Digital Processing Refines Scope Measurements	Val Garuts • Jim Tallman	1980	7854
42AX-4682.pdf	Introduction to 7854 Oscilloscope Measurement and Programming Techniques		1981	7854
7854 Application Programs.pdf	7854 Application Programs	Mike Mraz • Gary Kirchberger • Clark Foley • Roger Loop	1981	7854
AX-4281.pdf	Measurement Variety. An Engineering Challenge Featuring the 7854		1981	7854
AX-4864.pdf	7854 Waveform Calculator Keyboard Guide		1981	7854
42W-4416-1.pdf	Using the 7854 in a GPIB configuration		1982	7854 • GPIB
42W-5334.pdf	Automated TDR Testing Made Easy with the 7854 Oscilloscope/7S12 Sampler Plug-In		1983	7854 • 7S12
42W-5700.pdf	Power Supply/Device Testing		1984	7854
42W-5802.pdf	Basic software programs for communicating between the 7854 and IBM PC		1985	7854
42W-6732.pdf	TekMAP 7854 Time and Amplitude Measurement Software		1987	7854
42W-6767.pdf	Tektronix 7854TDR and 7854MPS measurement packages		1987	7854

Talking to the 7854 scope with TEK SPS BASIC (Handshake, Winter 1980/81)

Prices

Year	1981	1984	1990
Catalog price	$10,500	$14,230	$17,000
In 2023 Dollars	$35,500	$42,000	$39,900

Diagnostic Test Interfaces

Extender Boards

067-0913-00 Extender Board 44-Pin (used with the A30-GPIB and A31-ROM Boards)
067-0914-00 Extender Board 80-Pin (used with the A27-MPU and A28-RAM Boards)
067-0915-00 Extender Board 124-Pin (used with the A26-Control Logic and A29-Display Boards)

Software

Links

Talking to the 7854 Oscilloscope with TEK SPS BASIC in Handshake, Winter 1980/81
Tek 7854 Design Team Note: The graduation cap on the Engineering Release cake (page 8) signifies that it is the "Smart Scope".
Tek 7854 @ curiousmarc (with links to videos)
Tek 7854 @ amplifier.cd
7854 ROMs, the whole story @ TekScopes groups.io
Mostek ROM Repairs @ vintagetek.org
overview of ROM repair options @ paulcarbone.com

Internals

The acquisition system uses what Tektronix termed a "display-oriented random sampling digitizing technique".

It simultaneously digitizes a pair of X and Y signal values at a rate of 3.5 µs/point, using sample/hold circuits based on Schottky diode bridges, and a single 10-bit successive-approximation ADC. The Y sample value is then written into the memory location addressed by the X value, using DMA (direct memory access, i.e. bypassing the CPU).

The CPU in the 7854 is a Texas Instruments TMS9900 16-bit microprocessor, known from the infamous TI-99/4 home computer of the late 70s, with 32+6KByte ROM and 8KByte RAM.

The firmware consists of mask ROMs, an FPLA, and patch EPROMs. These ROMs (particularly the early ones from Mostek) are a common point-of-failure. Several remedies exist, see the Repairs page.

Pictures

Tektronix 7854 with Waveform Calculator keyboard, 7A26, 7M13, 7D15, 7B87
7854 Front with 7A26,7B85,7B87
7854 Rear, older version
7854 Rear, older version, separate RAM and ROM boards, external battery backup, old-style, silent fan
7854 Rear, newer version, combined RAM and ROM boards, internal battery backup, new-style, less silent fan
7854 Top
7854 Left
7854 Right
Waveform Calculator Keyboard
Waveform Calculator Keyboard
inside the Waveform Calculator Keyboard
Digital section in the 7854
A2 Mode Switch
A2 Mode Switch
The A7 / Auxiliary regulator
A different revision of the A7 board
A11 Main Interface
A15 Signal Output
A15 Signal Output
A15 Signal Out Board
A17 Horizontal Amp Board
A18 Vertical Amp Board
A19 Vertical Channel Switch
A19 Vertical Channel Switch
A20 High Voltage
A21 Z-Axis
A25 Digitizer
A26 Control Logic Board
A26 Control Logic Board
A26 Control Logic Board
A27 MPU
A different revision of the A27 board
A28 RAM Board
A28 RAM Board with option 2D (RAM Expansion)
A29 Display Board
A30 / GPIB board
A30 GPIB, different revision
A31 ROM Board
A32 Rear Panel Connector
Picture of 7854 during development. Note the different measurement keyboard layout. Picture might date from late 1978
Picture of designing the 7854 waveform calculator keyboard. note the different Keyboard layout.
Alignment Pattern
Program for generating Alignment Pattern
Mainframe rise time measured with 067-0587-02
7854 diagnostics system with MicroLab I

Memory Maps

Devices with separated ROM and RAM boards (SN < B100000)

Address Range	Size	ICs	Purpose
0000...3FFE	8k	U100, U110	ROM
4000...7FFE	8k	U200, U210	ROM
8000...8FFE	2k	U300, U310	PATCH ROM “for future use”
9000...9FFE	2k	U400,U410	PATCH + ROM
			2k RAM	4k RAM	8k RAM
A000...A7FE	1k	U510,U520,U530,U540	x	x	x
A800...AFFE	1k	U610,U620,U630,U640		x	x
B000...B7FE	1k	U710,U720,U730,U740			x
B800...BFFE	1k	U810,U820,U830,U840			x
C000...C7FE	1k	U110,U120,U130,U140			x
C800...CFFE	1k	U210,U220,U230,U240			x
D000...D7FE	1k	U310,U320,U330,U340		x	x
D800...DFFE	1k	U410,U420,U430,U440	x	x	x
E000...E37E			GPIB, Keyboards, Digitizer,...
E380...FFFE			Reserved for Diagnostic Interface

Devices with combined RAM+ROM Board (SN >= B100000)

Address Range	Size	ICs	Purpose
0000...7FFE	16k	U220,U320	ROM
8000...9FFE	4k	U200,U300	ROM for future use
A000...DFFE	8k	U400,U410	RAM
E000...E37E	4k		GPIB, Keyboards, Digitizer,...
E380...FFFE			Reserved for Diagnostic Interface

Devices with installed Diagnostic Boards (all serial numbers)

Address Range	Size	ICs	Purpose
0000...0FFE	2k	U430,U330	ROM
1000...1FFE	2k	U410,U310	ROM
2000...2FFE	2k	U200,U100	ROM
3000...3FFE	2k	U220,U120	ROM
4000...4FFE	2k	U420,U320	ROM
5000...5FFE	2k	U400,U300	ROM
6000...6FFE	2K	U210,U110	ROM
7000...7FFE	2K		ROM for future use
8000...7FFE	4k		Not used
9800...9FFE			RAM in Microlab I, disabled when standard ROM is in 7854
A000...DFFE	2...8k		RAM – see tables above
E000...E37E			GPIB, Keyboards, Digitizer,...
E380...E39E			BKREGCS Breakpoint address register chip select
E3A0...E3BE			CTREGCS control register chip select
E3C0...E3DE			BKDATA breakpoint data latch
E3E0			F/P Display Data
E3E2			F/P Display Data
E3E4			F/P Keyboard Data
E3E6			F/P Keyboard flag reset
E3E8			Terminal I/O Control
E3EA			Terminal I/O Data
E3EC			Cassette I/O Control
E3EE			Cassette I/O Data
E3F0			Modem I/O Control
E3F2			Modem I/O Data
E3F4...E3FE			ONBDIO on board input/output to microlab I
E400...E7FE			RAM in Microlab I
E800...EFFE		U120,U225	ROM - bank switched by PROMBK
F000...FFFE		U220,U320	ROM - bank switched by PROMBK

Components

Some Parts Used in the 7854

Part	Part Number(s)	Class	Description	Used in
154-0644-00	154-0644-00 • 154-0644-04 • 154-0644-05 • 154-0644-09 • 154-0893-05	CRT	CRT with distributed deflection plates	7704A • 7854 • 7904 • 7904A • R7903
155-0009-00	155-0009-00	Monolithic integrated circuit	horizontal lockout logic	7504 • 7514 • 7704 • 7704A • R7704 • 7834 • 7844 • 7854 • 7904 • R7903 • 7904A • 7934 • 7104
155-0010-00	155-0010-00	Monolithic integrated circuit	chop divider and blanking	7504 • 7514 • 7704 • R7704 • 7704A • 7834 • 7854 • 7904 • R7903 • 7904A • 7934 • 7104
155-0011-00	155-0011-00	Monolithic integrated circuit	clock and chop blanking	485 • 7313 • 7403N • R7403N • 7503 • 7504 • 7514 • 7603 • AN/USM-281C • 7613 • 7623 • 7623A • 7633 • 7704 • R7704 • 7704A • 7834 • 7844 • 7854 • 7904 • 7904A • R7903 • R7912 • 7912AD • 7912HB • 7934 • 7104 • R7103 • AN/USM-281C
155-0012-00	155-0012-00	Monolithic integrated circuit	Z Axis Logic	485 • 7504 • 7514 • 7704 • R7704 • 7704A • 7834 • 7844 • 7854 • 7904 • R7903 • 7904A • R7912 • 7934 • 7912AD • 7912HB • 7104 • R7103
155-0013-00	155-0013-00 • 155-0013-01	Monolithic integrated circuit	horizontal chop and alt. binary	7504 • 7514 • 7704 • R7704 • 7704A • 7834 • 7854 • 7904 • 7904A • R7903 • 7934 • 7104
155-0014-01	155-0014-00 • 155-0014-01	Monolithic integrated circuit	analog-to-decimal converter	7000 series readout system • 7854 • 7934 • 7J20 • 7L5 • P7001
155-0015-01	155-0015-00 • 155-0015-01	Monolithic integrated circuit	analog data switch	7000 series readout system • 7854 • 7934
155-0017-00	155-0017-00	Monolithic integrated circuit	5 MHz decade counter	7000 series readout system • 7854 • 7934
155-0021-00	155-0021-00 • 155-0021-01	Monolithic integrated circuit	timing generator	7000 series readout system • 7854 • 7934
155-0022-00	155-0022-00 • 155-0022-01	Monolithic integrated circuit	analog multiplexer	147 • 148 • 149 • 335 • 468 • 1430 • 1441 • 1461 • 1900 • 1910 • 2220 • 2221 • 2230 • 5223 • 5403 • 5440 • 5441 • 5443 • 5444 • 5A38 • 7313 • 7403N • 7503 • 7504 • 7514 • 7603 • AN/USM-281C • 7613 • 7623 • 7623A • 7633 • 7704 • R7704 • 7704A • 7834 • 7844 • 7854 • R7912 • 7912AD • 7912HB • 7904 • R7903 • 7904A • 7934 • 7A12 • 7A18 • 7A18A • 7A18N • 7B52 • 7B53N • 7D10 • 7D11 • 7D12 • NT-7000 • P7001
155-0059-00	155-0059-00	Monolithic integrated circuit	HF amplifier	7834 • 7844 • 7854 • 7904 • R7903 • R7912 • 7912AD
155-0064-00	155-0064-00	Hybrid integrated circuit	vertical output amplifier	7834 • 7854 • 7904 • R7903 • 7912AD • 485 • PG502
155-0067-02	155-0067-00 • 155-0067-02 • 155-0067-03	Monolithic integrated circuit	SMPS controller	7704A • 7834 • 7844 • 7854 • 7904 • R7903 • 7904 • 7904A • 7934 • R7912 • 7912AD • 7912HB • 7934 • 7104 • R7103 • 308 • 434 • 485 • 690 • P7001
155-0078-00	155-0078-xx • 155-0273-00 • 155-0274-00	Monolithic integrated circuit	broadband amplifier	464 • 465 • 466 • 468 • 475 • 475A • 475M • 485 • 7834 • 7844 • 7854 • 7904 • R7903 • R7912 • 7912AD • 7912HB • 7104 • 7A16A • 7A16P • 7A24 • 7A26 • 7A42 • 067-0587-01 • 067-0680-00 • AM503 • PG502 • PG508 • DC510 • DC5010 • FG5010
155-0167-01	155-0167-01	Hybrid integrated circuit	4-bit D/A converter	7854 • ADC820T
155-0187-00	155-0187-00	Monolithic integrated circuit	ft doubler amplifier	7854
155-0206-00	155-0206-00	Hybrid integrated circuit	channel switch	7854
MC3448	156-1133-02	Monolithic integrated circuit	GPIB bus driver	7854
MC68488	156-1246-00	Monolithic integrated circuit	GPIB controller	7250 • 7854 • CG551AP • CG5001 • CG5010 • CG5011 • Keithley 181 • Keithley 192
Mostek MK36000		Monolithic integrated circuit	8K×8 mask-programmable ROM	468 • 7854 • FG5010
Signetics 82S107		Monolithic integrated circuit	field-programmable logic array	4052 • 7854 • FG5010
Texas Instruments TMS9900	156-0935-00	Monolithic integrated circuit	16-bit microprocessor	1980 • 7854

@@ Line 16: / Line 16: @@
 * [[Media:Tektronix 7854 Test Point and Adjustment Locations D.pdf  | 7854 Test Points and Adjustment Locations]]
 * [[Media:Tektronix 7854 Schematics D.pdf                           | 7854 Schematics]] (cleaned up)
-'''Application Notes'''
-* [[Media:Tek_AX4864_7854_keyboard_guide.pdf             | Waveform Processing Keyboard Guide]] (OCR)
-* [[Media:Tek_AX4281_7854_measurement_variety.pdf        | 7854 Measurement Variety]] (OCR)
-* [[Media:Tek_AX4440_7854_onboard_digital_processing.pdf | 7854 Onboard Digital Processing]] (OCR)
-* [[Media:42W-4416-1.pdf                                 | Using the 7854 in a GPIB configuration]]
-* [[Media:42W-5334.pdf                                   | 7854 Automated TDR testing]] (OCR)
-* [[Media:42AX-4682.pdf                                  | 7854 Programming Techniques]] (OCR)
-* [[Media:Tek 7854-AN-SPSBasic.pdf                       | Talking to the 7854 scope with TEK SPS BASIC]] (''[[Handshake]]'', Winter 1980/81)
-* [[Media:7854 Application Programs.pdf                  | 7854 Application Programs]]
-* [[Media:Tek_AX4382_7854_wp1310_01.pdf|WP1310 Waveform Processing System]] (OCR)
-* [[Media:Tek_AX4425_7854_WP1310_02.pdf|WP1310 Signal Processing System]] (OCR)
-* [[Media:Tek_7854_42W6767_tdr_mps_package_sm.pdf|7854TDR and 7854MPS package]] (OCR)
-* [[Media:Tek_42W67321_Tekmap_7854_measurement.pdf|TekMAP 7854 Measurement Software]] (OCR)
 '''Modifications'''
@@ Line 96: / Line 80: @@
 {{EndSpecs}}
-==Internals==
+==Application Notes==
-The acquisition system uses what Tektronix termed a "display-oriented random sampling digitizing technique".
+{{Documents|Link=7854|Class=Application Note}}
+* [[:File:Tek 7854-AN-SPSBasic.pdf   | Talking to the 7854 scope with TEK SPS BASIC]] (''[[Handshake]]'', Winter 1980/81)
-It simultaneously digitizes a pair of X and Y signal values at a rate of 3.5 µs/point, using sample/hold circuits based on Schottky diode bridges, and a single 10-bit successive-approximation ADC.  The Y sample value is then written into the memory location addressed by the X value, using DMA (direct memory access, i.e. bypassing the CPU).
-The CPU in the 7854 is a [[Texas Instruments TMS9900]] 16-bit microprocessor, known from the infamous TI-99/4 home computer of the late 70s, with 32+6KByte ROM and 8KByte RAM.
-The firmware consists of mask ROMs, an FPLA, and patch EPROMs.  These ROMs (particularly the early ones from Mostek) are a common point-of-failure. Several remedies exist, see the [[7854/Repairs|Repairs]] page.
 ==Prices==
@@ Line 147: / Line 126: @@
 * [https://vintagetek.org/7854-mostek-mkb36000-rom-repairs Mostek ROM Repairs @ vintagetek.org]
 * [https://paulcarbone.com/blog/tektronix-7854/ overview of ROM repair options @ paulcarbone.com]
+==Internals==
+The acquisition system uses what Tektronix termed a "display-oriented random sampling digitizing technique".
+It simultaneously digitizes a pair of X and Y signal values at a rate of 3.5 µs/point, using sample/hold circuits based on Schottky diode bridges, and a single 10-bit successive-approximation ADC.  The Y sample value is then written into the memory location addressed by the X value, using DMA (direct memory access, i.e. bypassing the CPU).
+The CPU in the 7854 is a [[Texas Instruments TMS9900]] 16-bit microprocessor, known from the infamous TI-99/4 home computer of the late 70s, with 32+6KByte ROM and 8KByte RAM.
+The firmware consists of mask ROMs, an FPLA, and patch EPROMs.  These ROMs (particularly the early ones from Mostek) are a common point-of-failure. Several remedies exist, see the [[7854/Repairs|Repairs]] page.
 ==Pictures==