549: Difference between revisions

{{Oscilloscope Sidebar

|series=500-series scopes

|model=549

|summary=30 MHz storage oscilloscope

|image=Tek-549 and d.jpg

|caption=Tektronix 549 front

|introduced=1965

|discontinued=1974

|designers=Mel Holznagel;Bob Shand;

|manuals=

* [[Media:070-0508-00.pdf | Tektronix 549 Manual]] (OCR)

* [https://w140.com/mmm/tek-549.pdf Tektronix 549 Manual]

* [https://bama.edebris.com/manuals/tek/549 Tektronix 549 Manual] @ BAMA

 

* [[Media:tek_549_crt_socket_leak.pdf|Maintenance Note: 549 CRT Socket Leakage]] (OCR)

* [[Media:tek_549_note_ringing_1a1.pdf|Maintenance Note: 549 Ringing with 1A1]] (OCR)

 

* [[Media:tek_549_catalog.pdf|Tektronix 549 in 1968 Catalog]] (OCR)

* [[Media:tek_549_german_intro.pdf|Tektronix 549 Introduction in German]] (OCR)

* [[Media:tek_549_Remote_Control_DS.pdf|Tektronix 549 Remote Control Datasheet]] (OCR)

The '''Tektronix 549''' is the only [[CRT_storage_scope|storage scope]] in the 500 series (except for the [[537]] that never left prototype stage).

 

It takes a [[Letter-series_and_1-series_plug-ins|letter-series or 1-series vertical plug-in]].

The 549 was [[introduced in 1965]] and discontinued after 1973.   

The 549 vertical output stage was designed by [[Mel Holznagel]].  [[Bob Shand]] did the mechanical design.

{{Spec | Bandwidth | DC to 30 MHz (−3 dB) with fast plug-ins ([[1A1]], [[1A2]], [[1A4]], [[1A5]]) }}

{{Spec | Writing speed | 5 cm/μs }}

{{Spec | Line voltage  | 104/115/127 or 208/230/254 V_AC ±10%, selected via primary voltage selector (inside cabinet) and voltage range selector (on rear panel), 50 to 60 Hz }}

{{Spec | Thermal protection | 65°C (150°F) Automatic resetting [[thermal cutoff]] }}

{{Spec | Power consumption | 650 W, 750 VA }}

{{Spec | Size     | 43.2 cm × 32.9 cm × 60.7 cm (W/L/H, 13" × 24" × 17")  }}

{{Spec | Weight   | 31 kg (68 lb) }}

{{Spec | Accessories  | [[012-0102-00|012-0102-00 remote control cable/switch]] }}

In the 549, this buffer is implemented with a [[6DJ8]] cathode follower at the plug-in interface

driving an NPN BJT differential amplifier at the bottom of a cascode with a [[7119]] tube on top.   

Since the entire signal path is differential, the common-mode voltage does not have to be zero,

and it is not – the differential signal in the delay line rides on 167 volts of DC.   

After the delay line, the signal enters another cascoded differential amplifier with NPN BJTs

on the bottom and a pair of 10-watt [[8608]] power pentodes on the top whose plates drive the

CRT's vertical deflection plates of the CRT through inductive matching/peaking networks.

The 549 uses the [[T5490]] CRT which has two storage targets, upper and lower,

 

It connects to an [[Amphenol 165 series connectors|Amphenol 165-16 socket]] at the rear top of the scope (see [[549 remote control connector]] for pin-out).

===Power Supply===

The 549's power supply provides regulated outputs of −12.4 V, −150 V, +100 V, +225 V, +300 V, +350 V, and +500 V as well as a +475 V unregulated output.

Line input is connected to main transformer primary via two switches, one inside the chassis to select the 110 V or 230 V range, and another on the rear of the chassis to select Low/Medium/High voltage in either range.

Multiple secondary windings feeds diodes for rectification for different voltages. Both center-tap and bridge configuration is used. Transistors and/or tubes are used for regulation.  

As is common in many Tektronix scopes, all regulated voltages are referred to the negative regulated rail (−150 V in this case) by fixed low-tolerance dividers.  Only the −150 V voltage is trimmed, its reference is a [[5651]] VR tube.  A [[12AX7]] is used as the comparator, three [[12B4]] in parallel are used as series pass tubes. A [[6AU6]] is used as an error amplifier.

Most other stages replicate the same design, except slight changes in tubes used − the +350 V, +225 V and +100 V regulators employ a [[6080]] as the pass element.

The −12.4 V regulator is transistor-based.

The 549 power supply uses a [[delay relay|6N030 delay relay (P/N 148-0021-00)]] to control a relay that switches supply voltages on only after the tubes are warmed up. On power up, only heater voltage is applied to the tubes. After a delay of up to 60 seconds, the thermal delay relay activates the main relay (driven from unregulated +170 V). This also cuts out the delay relay, which can cool down and will be ready to delay again even after a quick interrupt in power input.

The 549 has a 65°C (150°F) [[thermal cutoff]].

* [https://lazyelectrons.wordpress.com/2018/01/11/tektronix-549-restoration/ Rajesh's Tek 549 Restoration] / [https://www.youtube.com/watch?v=8rWH-uuf60U Video]

Tek-549 and d.jpg               | 549 front, earlier round bezel

Tek 549 mt1.jpg                 | 549 front, later rectangular bezel

Tek-549-front.jpg

Tek 549 trace2.jpg               |  

Tek_549-Front.jpeg              |

Tek_549-Stroage-Ctrl.jpeg        | 549 Storage controls

Tek 549 trace2..jpg             |

Tek 549 trace.jpg               |

Tek 549 front fl.jpg             |

549_front.jpg                   | Front of a 549

Wellenkino 549-1.jpg             |

Tek 549 front fl.jpg             |

Tek 549 1a4 1.jpg               |

Tek 549 1a4 2.jpg               |

Tek 549 1a4 3.jpg               |

Tek 549 1a4 4.jpg               |

549_Delayed_Trace.jpg           | B INTEN BY A Trig in 549

549_Dual_Trace.jpg               | Dual trace display in 549

Tek 549-1 knob layout.jpg       | 549 knob layout

Tek 549 - Electronics 1965-08-23.jpg | 549 ad in Electronics 1965-08-23