7603

Manuals – Specifications – Links – Pictures

The Tektronix 7603 is a general-purpose 100 MHz non-storage, large-screen scope that takes two 7000-series vertical plug-ins and one 7000-series horizontal plug-in.

Variants include the a rack-mount version (R7603), and the AN/USM 281C, a ruggedized 7603 without readout (was also known as 7603N Option 11S) that includes two AM-6565 (7A15AN11) single-trace amplifiers, a TD-1085 (7B53AN11) dual time base, and a clip-on front panel cover with probes and accessories.

Key Specifications

Bandwidth	100 MHz with 7A11, 7A16, 7A17, 7A24, 7A26; 110 MHz with 7A19, 70 MHz with 7A18
Fastest calibrated sweep	5 ns/Div
CRT	Standard: P31 phosphor, 8 × 10 divisions of 1.22 cm (Tek T7400/154-0640-00 tube); 15 kV acceleration (-3/+12); Option 8: P11 phosphor Opt. 4 : P31 phosphor, 8 × 10 divisions of 1.0 cm (Tek 154-0672-00 tube); 18 kV acceleration Opt. 6 : P31 phosphor, 8 × 10 divisions of 1.22 cm (Tek 154-0673-00 tube, spectrum analyzer graticule)
Vertical modes	Left / Alt / Add / Chop / Right
Trigger Source	Left / Vert Mode / Right
Inputs	Z Axis
Outputs	Camera power, Vert signal, +Gate, +Sawtooth
Power	100 / 110 / 120 / 200 / 220 / 240 V, +/- 10%, 50—440 Hz, max. 170 W
Weight	13.6 kg / 30 lb (instrument only)
Operating Environment	0°C – +50°C, < 15,000 ft

Options

Due to the long production time of the 7603 many options were available. As some options became standard (e.g. built-in fan) some numbers were assigned twice. Later models were equipped with an IEC320 mains socket, making all Ax (power cable style) options obsolete.

• Opt.1: Without readout (= 7603N)
• Opt.3: Extra EMI shielding
• Opt.4/Opt.13: Maximum-brightness CRT with reduced area (8x10 cm graticule)
• Opt.5: Fan
• Opt.5 (later models): 400 Hz line frequency
• Opt.6: Spectrum analyzer graticule
• Opt.7: Without Signals Out
• Opt.8: P11 phosphor
• Opt.8 (later models): protective front panel cover, 7603 only
• Opt.11S: Ruggedized variant AN/USM 281C, specified at 50 MHz
• Opt.20: Rear GPIB socket for 7D20, removes +Sawtooth, +Gate, vertical signal outputs, R7603 only
• Opt.76: P7 phosphor
• Opt.77: P7 phosphor with spectrum analyzer graticule
• Opt.78: P11 phosphor

Internals

The 7603 was made in various versions for many years, with revisions to some subassemblies like the vertical output amplifier and HV circuits. A fan is optional.

The vertical output amplifier is built around a 155-0080-00 hybrid (U450). CRT deflection plates are not distributed.

Other custom Tek ICs used include 155-0011-00 clock & chop blanking (U55), 155-0022-00 vertical channel switch (U214), 155-0022-00 trigger channel switch (U324),and the 7000 series readout system chips.

Modifications

Official Modification 36005 added a ground strap to the vertical amplifier to prevent >1 GHz oscillations.

Like the other 76xx models, the 7603 has a linear supply which does not provide +5 V for lights (A9). There was an official Tek modification to add pushbutton illumination for plugins, which involves adding a regulator, but there is also a quick'n'dirty method from Rolynn Prechtl:

I've done multiple units the cheap and dirty way. No additional regulator, no pulling the LVPS to find a place to add extra components and the best part, no cost.
Look for P90 and P10 on the rear edge of the Main Interface ECB (left side as I remember).
Connect P10-1 (GND) P90-7 or 8 (GND).
Connect P10-2 (+5 V) to P90-4 (+5 V).
Two wires and you're done.
Have experienced no problems with the extra current demand from the +5V regulated supply.

Prices

	Year	1973	1976	1980	1984	1990
Mainframe only	Catalog price	$1,600	$1,800	$2,260	$2,865	$4,235
	2019 value	$9,160	$8,040	$6,970	$7,010	$8,240
Mainframe with 2 × 7A18 + 7B53	Catalog price	$3,520	$3,955	$5,225	$6,880	$10,315
	2019 value	$20,150	$17,670	$16,120	$16,830	$20,060

Links

• Detailed repair report @ amplifier.cd (German) / (translated)
• Tek 7603 @ barrytech.com
• Catalog page with specs
• Repair Report #2
• Repair Report #3
• Repair Report #4 - 7603 with 7D20
• EB5AGV's Tektronix R7603 / 7D20 page
• Picture of a completely disassembled 7603
• Håkan's 7603 PSU re-cap

Pictures

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  Tektronix 7603, front view with display

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  Tektronix 7603, front view

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  7603 Option 8 (blue P11 phosphor)

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  R7603

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Internal

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  7603, left side - center left: vertical amplifier

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  7603, right side - left: calibrator, center left: readout, center right: cover of HV board

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  7603, top view - top: Z axis board, bottom: horizontal amplifier board

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  HV board (below SN B330000)

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  HV board (later version, DC restorer circuits on daughter boards, neons)

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  Interior view of rear panel showing part of LV regulator board (version without fan)

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  Rear view with LV regulator board flipped out (version without fan)

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  Low voltage regulator board

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  Low voltage regulator board fixed for maintenance

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  Bottom view of backplane. Backplane interconnect board is seen in center, vertical interface and trigger selector piggyback boards on left/top left, logic board on right.

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  Logic board (normally situated on back of main interconnect facing the PSU)

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  Trig Select and Vertical Interface boards

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  Backplane interconnect without Vertical Interface and Trigger Selector piggyback boards

Modifications

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  Pushbutton illumination supply using a small step-down regulator module

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Custom ICs used in the 7603

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