647: Difference between revisions

Revision as of 09:09, 31 October 2023

Tektronix 647

50 MHz scope

Produced from 1963 to 1967

Manuals

Tektronix 647 Manual
Tektronix RM647 schematics (large format)
tentative specifications.pdf
Tektronix 647 HV transformer winding data
Type 647 Notes (needs OCR)
Tektronix Type 647 and 647A Calibration Outline (OCR)

Alternate copies

Tektronix 647A Manual (DjVu @ BAMA)

(All manuals in PDF format unless noted otherwise)

Manuals – Specifications – Links – Pictures

The Tektronix 647 is a 50 MHz oscilloscope with plug-ins for both vertical and horizontal deflection. It was introduced in late 1963, along with a minimal set of plug-ins, and replaced by the higher bandwidth 647A in 1967. Except for the CRT and the rectifiers in the HV power supply, the 647 is all solid state.

The original 647 project leader was Oz Svehaug in 1962. From 1963 onward, the project was led by Oliver Dalton.

The intent was to offer a higher performance scope in a small form factor, roughly the size and weight of the 560 series. Additionally, the 647 was promoted as “ruggedized” with an extended operating temperature range, and higher shock and vibration ratings than previous lab grade instruments.

The 647 uses 10 series vertical and 11 series time base plug-ins. At introduction, the 10A2 a dual channel 50 MHz vertical, 11B1 single time base, and 11B2 dual time base were offered. A differential comparator, the 10A1 was introduced in 1965. These plug-ins are unique to the 647 and 647A.

Key Specifications

Bandwidth	DC to 50 MHz with Type 10A2 plug-in
Rise time	5.8 ns
Bandwidth	DC to 45 MHz (35MHz at <5mV/div) with Type 10A1 plug-in
Rise time	7.8 ns (10ns at <5mV/div)
Acceleration voltage	14 kV
Screen Area	6 cm × 10 cm
Power	108/115/122/216/235/244 V_AC ±10%,selected via primary voltage selector and voltage range selector switches, 50 Hz to 60 Hz; 185W with 10A2 & 11B2 plug-in
Construction	Aluminum alloy chassis. Anodized front panel
Operating Temperature	-30 C° to +65 C°
Cooling	AC Fan (only in rack variant)
Thermal Protection	Automatic resetting thermal cutout, in case internal temperature exceeds safe operating level
Weight	40.5 lbs / 18.4 kg

Internals

Unlike the threaded knob used for retaining the 530/540 series plug-ins, the 647 uses a lever actuated cam mechanism. The single lever both engages and disengages the plug-in with a quick, smooth motion. Many users considered it to be the best plug-in retaining system Tek had ever offered.

Unlike the 560 series where the plug-ins directly drive the CRT deflection plates, the 647 has amplifiers for both the vertical and horizontal signals in the mainframe. In addition to supporting the higher bandwidth, the amplifiers provide a normalized gain at the plug-in interface, eliminating the need to adjust the gain or sweep cal every time a plug-in was swapped.

The 647 has a 140 ns delay line between the vertical plug-in connector and the input of the vertical amplifier. The interface between the vertical plug-in and the mainframe is a 93 Ω controlled-impedance connection. This is in contrast to the 500-series scopes, which appear to the plug-in as a high impedance.

The horizontal and vertical plug-ins are not electrically interchangeable. Only a 10 series plug-in will work in the vertical compartment, and only a 11 series time base will work in the horizontal compartment. X-Y mode requires the use of the external horizontal input in an 11 series time base.

The 647 uses the T6470 CRT with electromagnetic trace rotation and 14 kV total accelerating voltage. The HV power supply contains five 5642 rectifier tubes: three for the +11.2 kV CRT anode supply, one for the -2.2 kV CRT cathode, and one for the -2.2 kV CRT grid/blanking.

The calibrator in the 647 is based on a 4 kHz crystal, which is divided down to 1 kHz. Its specified tolerance is ±1 Hz.

The solid extender for 647 plug-ins is the 013-077.

Pictures

647

647 with 10A1 and 11B2
647 Right Side
647 with MOD165K

647A

647A Front View
647A Left View
647A Right View
647A Rear View
647A with 10A1 and 11B2A
647A
647A
647A rear connections
10A2A and 11B2A in 647A
647A
647A
647A
647A
647A
647A
647A
647A
647A
647A

RM647

RM647 Front View
RM647

Components

Some Parts Used in the 647

Part	Part Number(s)	Class	Description	Used in
5642	154-0051-00 • 154-0079-00	Vacuum Tube (Diode)	directly-heated high-voltage rectifier	310 • 310A • 316 • 317 • 360 • 453 • 502 • 502A • 503 • 504 • 506 • 513 • 515 • 516 • 524 • 529 • RM529 • 533 • 533A • 535 • 536 • 543 • 543A • 543B • 545 • 545A • 545B • 547 • 551 • 555 • 556 • 560 • 561 • 561A • 561S • 564 • 567 • 570 • 575 • 581 • 581A • 585 • 585A • 647 • 647A
T6470	154-0434-00 • 154-0448-00	CRT	CRT	647 • 647A

Some Parts Used in the 647A

Part	Part Number(s)	Class	Description	Used in
2N3119	151-0124-00	Discrete component	NPN VHF power transistor	647A
2N3866	151-0211-00	Discrete component	NPN VHF power transistor	647A
5642	154-0051-00 • 154-0079-00	Vacuum Tube (Diode)	directly-heated high-voltage rectifier	310 • 310A • 316 • 317 • 360 • 453 • 502 • 502A • 503 • 504 • 506 • 513 • 515 • 516 • 524 • 529 • RM529 • 533 • 533A • 535 • 536 • 543 • 543A • 543B • 545 • 545A • 545B • 547 • 551 • 555 • 556 • 560 • 561 • 561A • 561S • 564 • 567 • 570 • 575 • 581 • 581A • 585 • 585A • 647 • 647A
T6470	154-0434-00 • 154-0448-00	CRT	CRT	647 • 647A

Some Parts Used in the RM647

@@ Line 31: / Line 31: @@
 The 647 uses 10 series vertical and 11 series time base plug-ins.
 At introduction, the [[10A2]] a dual channel 50 MHz vertical, [[11B1]] single time base, and [[11B2]] dual time base were offered.
-These plug-ins are unique to the 647 and 647A.
+A differential comparator, the [[10A1]] was introduced in 1965. These plug-ins are unique to the 647 and 647A.
 {{BeginSpecs}}
-{{Spec | Bandwidth   | DC to 60 MHz with [[10A2|Type 10A2 plug-in]]  }}
+{{Spec | Bandwidth   | DC to 50 MHz with [[10A2|Type 10A2 plug-in]]  }}
 {{Spec | Rise time   | 5.8 ns }}
+{{Spec | Bandwidth   | DC to 45 MHz (35MHz at <5mV/div) with [[10A1|Type 10A1 plug-in]]  }}
+{{Spec | Rise time   | 7.8 ns (10ns at <5mV/div) }}
 {{Spec | Acceleration voltage | 14 kV}}
 {{Spec | Screen Area | 6 cm × 10 cm}}