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Tektronix TDS784
1 GHz, 4 GS/s 4-channel digital scope
Tektronix TDS784D

Produced from 1995 to (?)






(All manuals in PDF format unless noted otherwise)
Manuals – Specifications – Links – Pictures

The Tektronix TDS784 is a 1 GHz, 4 GS/s four-channel digital storage scope with a color screen.
There are four variants, all with the same specs but different hardware/software loads − TDS784A, B, C & D. Of these, the C and D models are the least problematic and most sought-after.

Key Specifications

Bandwidth 1 GHz at 10 mv/div and above; 750 MHz @ 5 mV/div; 600 MHz @ 2 mV/div; 500 MHz @ 1 mV/div
Sample rate 1 channel @ 4 GS/s, 2 channels @ 2 GS/s, 3 or 4 channels @ 1 GS/s
Number of Channels 4
Vertical Sensitivity 1 mV to 10 V/div with calibrated fine adjustment
Resolution 8 bit
Time Base Range 200 ps to 10 s/div
Record length 50k samples per channel
Record Length (1M Option) 500 K points on 1 channel; 250 k points on 2 channels ; 130 k points on 3 or 4 channels
Record Length (2M Option) 8 M points on 1 channel; 4 M points on 2 channels ; 2 M points on 3 or 4 channels
Acquisition modes sample, envelope, average, high-resolution, peak-detect
Display Color; Zoom
Trigger modes Edge, logic, pulse; Video trigger with option 05 (NTSC, SECAM, PAL, HDTV, and FlexFormat)
Storage 1.44 Mbyte, 3.5 inch, DOS 3.3-or-later floppy disk. NVRAM storage for saving waveforms, hardcopies, and setups. Units with option HD present (requires additional hardware) have a hard disk drive
I/O Full GPIB programmability
Hardcopy Using GPIB, RS-232, or Centronics ports




  • 05 - Video Trigger - Oscilloscope comes with tools that allow investigation of a range of NTSC, PAL, SECAM, and high definition TV signals.
  • 13 - RS-232C and Centronics hardcopy interfaces - Add RS-232-C and Centronics interface ports.
  • 1F - Floppy disk drive - Add 3.5 inch, 1.44 MByte floppy disc drive.
  • 1G - 1 GS/s maximum - Limit sample rate from 5 GS/sec to 1 GS/sec when acquiring 1 to 4 channels (Export restriction compliance). (TDS 754D Only)
  • 1M - 4M acquisition length - Extends standard acquisition length from 50,000 points per channel to 130,000 samples on three or four channels, 250,000 samples on two channels, and 500,000 samples on one channel.
  • 2C - Communication Signal Analyzer - Oscilloscope comes configured for communications signal triggering and mask testing.
  • 2F - Advanced DSP math - Add advanced DSP math features such as FFT, integration, and differentiation.
  • 2M - 8M acquisition length - TDS 520D, 724D: To 2M samples on two channels and 4M on one channel. TDS 540D, 580D, 714L, 754D, 784D, 794D: To 2M samples on three or four channels, 4M on two channels, and 8M samples on one channel (Option includes a hard disk and is only available for the models listed above.)
  • 3C - P6701B with system calibration - Oscilloscope comes with a P6701B and calibrated short-wavelength optical reference receiver on channel 1.
  • 4C - P6703B with system calibration - Oscilloscope comes with a P6703B and calibrated long-wavelength optical reference receiver on channel 1.
  • HD - Hard Disk - 170Mb internal hard disk drive.

Optional Accessories

  • 1K - Add K420 scope cart
  • 1R - Rackmount kit
  • 24 - Add 4 each P6139A passive probes
  • 26 - Add 4 each P6245 active probes
  • 3I/3P - Colour printer and cable (220V/110V)
  • B2 - Hardcopy version of the programmers manual
  • L1 - Substitute French user manual
  • L3 - Substitute German user manual
  • L5 - Substitute Japanese user manual
  • L9 - Substitute Korean user manual

Included Accessories

  • 020-2204-00 - Quick Reference in 8 languages
  • 070-6869-00 - User Manual
  • 070-9874-01 - Technical Reference
  • 063-2773-00 - Programmer's Manual in MS-Help format on floppy disk
  • NIST, MIL-STD-45662A and ISO9000 calibration certificate
  • 200-3696-01 - Front cover
  • 161-0230-01 - US power cord
  • 016-1268-00 - Accessory pouch

Recommended Accessories

  • 070-9875-00 - Service Manual
  • 012-0991-01 - 1m GPIB cable
  • 012-0991-00 - 2m GPIB cable
  • 012-1298-00 - RS-232 cable
  • 012-1250-00 - Centronics cable
  • 016-0909-01 - Soft-sided carrying case
  • 016-01135-00 - Transit case
  • K420 - Scope cart

Software Options

  • LVWIN - LabVIEW for PC Windows OS
  • LWCVI - LabWindows for CVI system
  • LWDOS - LabWindows for DOS OS
  • S3FT400 - WaveWriter AWG and waveform creation software
  • TTiP - Telecommunications Templates and i-Pattern software
  • WSTR31 - WaveStar waveform capture and documentation software


See the Repairs page regarding HDD/FDD replacements.


For units with serial numbers prior to B04xxxx, the latest known firmware revision is 6.6e. For units with serial numbers B04xxxx and above, the last known version is 7.4e. Note that, due to differences in acquisition and CPU board hardware, release 7.4e will not work in the earlier revision units. Early revision units may have a CPU board P/N of 679-4172-00. The later revision is 679-4349-00.

It is also worth noting the TDS754 and TDS784 series are nearly identical, with the differences being in front-panel cosmetics and the presence (754) or absence (784) of a few capacitors on the acquisition board. The only other difference is the position of instrument ID jumpers, also on the acquisition board. In fact, it is entirely possible to convert a 754 to a 784 (see the 'Links' section).

Note that any kind of firmware updating of the 784 (and most other similar TDS scopes) requires very specific equipment, starting with an older computer (ISA slots required) running MS-DOS 5.x or later as well as Windows 98SE. To interface with the scope, you will need a National Instruments PC/GPIB-II ISA-based (8-bit) GPIB board or a National Instruments AT-GPIB (16-bit) board and appropriate drivers. The software required to do the update (Tektool or Tekfwtool) also runs under DOS (or a DOS box in Windows 98). Information on this tool can be found in the Links section in the thread describing firmware updates.
Using the 'Unified Tektool', a firmware update can be achieved using a standard USB-GPIB adapter as detailed in this link. Be sure to backup BOTH your firmware AND NVRAM before writing the new firmware in!
If the new firmware does not work in your scope, a full clear of the firmware and NVRAM and then loading your backed up firmware and NVRAM back in will have it working again on the original firmware.

Actual calibration requires the above computer, the specific PC/GPIB-II card and drivers and an MS-DOS environment. You will also need an Analogic/Data Precision model 8200 DC voltage standard and a levelled sine-wave generator capable of going up to 1 GHz (if you're just doing a 754, you can get away with a 500 MHz top end). Naturally, Tek used the SG503 and SG504.

The reason for the specific model of voltage standard is because that's the model Tektronix wrote the calibration software for. During the calibration process, it issues automated commands specific to the Analogic.

Note that in the TDS700D series, the acquisition board variant is important — the CPU Board with Firmware 7.xx cannot be used together with the old acquisition board, and the CPU board with old Firmware 6.xx doesn't run with the new acquisition board. The fact that the CPU board has part number 671-4349-00 is by itself not a reliable indication of a compatible firmware version.

Finally, for those with a dimming CRT, Simmconn Labs has developed a color LCD panel kit to replace said CRT in most of the TDS series which use them.



Some Parts Used in the TDS784A

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Some Parts Used in the TDS784B

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Some Parts Used in the TDS784C

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Some Parts Used in the TDS784D

Part Part Number(s) Class Description Used in
M377 165-2129-03 165-2089-06 155-2089-05 Monolithic integrated circuit amplifier 11A16 11A32 11A33 11A34 11A52 2245 2245A 2247 2247A 2252 TDS410 TDS420 TDS460 TDS520D TDS540D TDS580D TDS680C TDS684C TDS714L TDS724D TDS754D TDS784D