The Tektronix 7504 is a 90 MHz 7000-series mainframe, one of the initial oscilloscopes introducing the 7000-Line in 1969. The 7504 development team was led by Wim Velsink.

Tektronix 7504
90 MHz non-storage mainframe
Tektronix 7504

Produced from 1969 to 1971

Manuals
(All manuals in PDF format unless noted otherwise)

It is very lavishly built, using contacts embedded in the aluminium frame for interconnecting the gold plated circuit boards. It also features the 7000-series remote control connector on the rear panel.

It can take two 7000-series vertical plug-ins and two 7000-series horizontal plug-ins., and was in production for about one year.

Key Specifications

Bandwidth 90 MHz
Fastest calibrated sweep 5 ns/Div
Calibrator DC, square wave (1 kHz or ½ B Sweep gate), 4 mV to 40 V in decade steps (2/20/200/400 mV into 50 Ω); 40 mA current loop
Vertical modes Left / Alt / Add / Chop / Right
Horizontal modes A / Alt / Chop / B
Trigger Source Left / Vert Mode / Right
Inputs
  • Z Axis High Speed (60 Vp-p, DC−75 MHz)
  • Z Axis High Sensitivity (2 Vp-p, DC−2 MHz; 0.4 Vp-p @ 10 MHz)
Outputs
  • Vertical Signal Out (25 mV/Div into 50 Ω, 0.5 V/Div into 1 MΩ)
  • +Sawtooth
  • +Gate
  • camera power
  • probe power
CRT 8x10 Div @ 1 cm/Div internal gradicule, 154-0608-00 with P31 phosphor 18 kV acceleration (+15/-2.96)
Options
  • Opt.01 – without readout
  • Opt.02 – X-Y compensation network
  • Opt.03 – EMI shielding
Power 90−136 V or 180−272 V, 48−440 Hz, 280 W max.
Weight 24.6 kg (54 lb)
Size
34.2 cm × 30.5 cm × 62.2 cm (H×W×L)
(13.5 in x 12.0 in x 24.6 in)

Operation

The 7504 has several modes of operation, all outlined in the manual:

Single-Trace Display
Vertical Mode: Left, Horizontal Mode: A. Single-trace vertical plugin installed in the left vertical compartment, single-timebase plugin installed in horizontal compartment A.
Provides a display of a single-trace vertical unit against one time-base unit.
Note: Any combination of one vertical and one horizontal plugin can be chosen as needed.
Dual-Trace Display
Vertical Mode: Alt or Chop, Horizontal Mode: A. Single-trace vertical plugins installed in both vertical compartments, single-timebase plugin installed in horizontal compartment A.
Provides a display of two single-trace vertical units against one time-base unit.
Dual-Sweep Display
Vertical Mode: Left, Horizontal Mode: Alt or Chop. Single-trace vertical plugin installed in the left vertical compartment, single-timebase plugins installed in both horizontal compartments.
Provides a dual-sweep display of a single-trace vertical unit against two time-base units.
Dual-Trace/Dual-Sweep Display
Vertical Mode: Chop, Horizontal Mode: Alt or Chop. Single-trace vertical plugins installed in both vertical compartments, single-timebase plugins installed in both horizontal compartments.
Provides a dual-trace, dual-sweep display of two single-trace vertical units against two time-base units (four total traces)
Sweep-Slaving Display
Vertical Mode: Alt, Horizontal Mode: Alt or Chop. Single-trace vertical plugins installed in both vertical compartments, single-timebase plugins installed in both horizontal compartments.
Provides a dual-trace, dual-sweep display where the left vertical plugin is displayed at the sweep rate of the B timebase plugin, and similarly for the right vertical and B horizontal plugins.
Delayed-Sweep Display
Vertical Mode: Left, Horizontal Mode: Alt or Chop. Single-trace vertical plugin installed in the left vertical compartment. Delaying timebase plugin installed in horizontal compartment A, and a single-timebase plugin installed in horizontal-compartment B.
Provides a simultaneous display of a delaying timebase and delayed timebase, providing an effective "zoom" function.
X-Y Display
Vertical Mode: Left, Horizontal Mode: A. Single-trace vertical plugins installed in both the left vertical compartment and the A horizontal compartment.
The X signal is input into the A horizontal plugin while the Y signal is input into the left vertical plugin. Alternatively, some 7B series timebase plugins include X-Y capability.

Due to the modular design of the instrument, there are many more possible modes of operation. For example, horizontal plugins can be installed in both the vertical and horizontal plugins to provide a raster display, or dual-trace plugins can be used in any of the above configurations.

Internals

Like other 75xx and 76xx mainframes, the 7504 has a linear power supply, as opposed to the switchmode supplies used in the later 4-slot mainframes.

It is equipped with a rear remote control connector similar to the 7904 but lacking the remote readout features, and two probe power connectors.

Logic, channel switching, and readout use the classic TEK 7000 series custom ICs (155-0009-00 to 155-0022-00), the vertical amplifier (also designed by Andrews) and the horizontal amplifier are completely discrete.

The 7504 does not implement the Aux Y input (B16), therefore the Trace Separation control on a 7B92/7B92A will have no effect.

The 7504 contains a mercury-based elapsed time meter on the low voltage regulator board.

Links

Documents Referencing 7504

Document Class Title Authors Year Links
Tekscope 1969 V1 N5 Oct 1969.pdf Article Introducing the New Generation 1969
Tekscope 1969 V1 N6 Dec 1969.pdf Article A New Logic for Oscilloscope Displays 1969
Tekscope 1970 V2 N3 Jun 1970.pdf Article The 7000-Series Oscilloscopes as Signal Sources 1970

Patents that may apply to 7504

Page Title Inventors Filing date Grant date Links
Patent US 3453403A Power selection device Eldon Hoffman 1966-08-18 1969-07-01

Pictures

Components

Some Parts Used in the 7504

Part Part Number(s) Class Description Used in
120-0626-00 120-0626-00 Discrete component power transformer 7504
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
155-0022-00 155-0022-00 155-0022-01 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
2N3739 151-0201-00 Discrete component Silicon NPN power transistor 013-002 106 4501 561B R561B 564B R564B 568 7503 7504
T7500 154-0608-00 CRT CRT 7503 7504


Custom ICs used in the 7000 series readout system

Page Model Part nos Description Designers Used in
155-0014-01 M019D 155-0014-00 155-0014-01 analog-to-decimal converter Barrie Gilbert 7000 series readout system 7854 7934 7J20 7L5 P7001
155-0015-01 M020F 155-0015-00 155-0015-01 analog data switch Barrie Gilbert 7000 series readout system 7854 7934
155-0017-00 M025 155-0017-00 5 MHz decade counter Barrie Gilbert 7000 series readout system 7854 7934
155-0018-00 M026 155-0018-00 zeros logic control Les Larson 7000 series readout system 7934
155-0019-00 M027 155-0019-00 decimal point and spacing control Les Larson 7000 series readout system
155-0020-00 M028 155-0020-00 output assembler Les Larson 7000 series readout system
155-0021-00 M029C 155-0021-00 155-0021-01 timing generator Les Larson 7000 series readout system 7854 7934
155-0023-00 M160 155-0023-00 character generator (0 1 2 3 4 5 6 7 8 9) Barrie Gilbert 7000 series readout system
155-0024-00 M161 155-0024-00 character generator (↓ < I / + - + C Δ >) Barrie Gilbert 7000 series readout system
155-0025-00 M162 155-0025-00 character generator (m μ n p X K M G T R) Barrie Gilbert 7000 series readout system
155-0026-00 M163 155-0026-00 character generator (S V A W H d B c Ω E) Barrie Gilbert 7000 series readout system
155-0027-00 M164 155-0027-00 character generator (U N L Z Y P F J Q D) Barrie Gilbert 7000 series readout system