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{{Oscilloscope Sidebar | | {{Oscilloscope Sidebar | ||
|manufacturer=Tektronix | |||
summary=50 MHz | |model=547 | ||
image=Tek 547 | |summary=50 MHz oscilloscope | ||
caption=Tektronix 547 with [[ | |image=Tek 547 D-Alt-Trace.jpeg | ||
introduced=1964 | | |caption=Tektronix 547 with [[1A1]] plugin, in ALT Delayed Trigger | ||
discontinued=1975 | | |introduced=1964 | ||
manuals= | |discontinued=1975 | ||
* [ | |designers=Bob Rullman;Keith Taylor;John Gates;Gene Kauffman;George Smith | ||
* [ | |series=500-series scopes | ||
* [ | |manuals= | ||
* [[Media:070-0398-00.pdf|Tektronix 547/RM547 Manual]] <small>070-0398-00, plus "547 Notes"</small> (OCR) | |||
* [[Media:Tek_547_544_546_tech_instr_and_training.pdf|Tektronix 544/546/547 Technical Instruction and Training]] (OCR) | |||
* [[Media:Tek 547 fcp.pdf|Tektronix 547 Factory Calibration Procedure]] | |||
* [[Media:Tek 547 cal procedure.pdf]] | |||
<small> | |||
'''Alternate versions''' | |||
* [https://bama.edebris.com/download/tek/547/547.djvu Tektronix 547 Manual] (DjVu @ BAMA) | |||
* [[Media:070-0398-00 (2).pdf|Tektronix 547 Manual 070-0398-00]] | |||
</small> | |||
<small> | |||
'''Modifications''' | |||
* [[Media:Tek 547 mods.pdf|Tektronix 547 Modifications]] | |||
* [[Media:050-0479-01.pdf|Disconnect Diode 547/R547 Serials 100-12479]] Tek Part [[050-0479-01]] | |||
</small> | |||
}} | }} | ||
The '''Tektronix 547''' is a 50 MHz scope that takes [[letter-series and 1-series plug-ins]]. | The '''Tektronix 547''' is a 50 MHz scope that takes [[letter-series and 1-series plug-ins]]. | ||
It has two identical timebases and, | |||
when used with the [[1A1]], [[1A2]], or [[1A4]], | It has two identical timebases and, when used with the [[1A1]], [[1A2]], or [[1A4]], | ||
has the ability to display one input with one time scale and another input with a different time scale. | has the ability to display one input with one time scale and another input with a different time scale. | ||
The effect is similar to a [[dual-beam scopes|dual-beam scope]] | The effect is similar to a [[dual-beam scopes|dual-beam scope]] | ||
Line 21: | Line 35: | ||
There is also a rackmount version, the RM547 or R547. | There is also a rackmount version, the RM547 or R547. | ||
The | The program manager for the development of the Tektronix [[544]], [[546]], and 547 was [[Bob Rullman]]. | ||
The 547 vertical amplifier was designed by [[Keith Taylor]]. | |||
{{BeginSpecs}} | |||
{{Spec | Bandwidth | DC to 50 MHz (−3 dB) with fast plug-ins ([[1A1]], [[1A2]], [[1A4]], [[1A5]]) }} | |||
{{Spec | Rise time | 7 ns with [[1A1]] }} | |||
{{Spec | Sweep Rates | 100 ns/div to 5 s/div}} | |||
{{Spec | External Horizontal Input | 100 mV/cm to 10 V/cm, DC to 400 kHz}} | |||
{{Spec | CRT | [[T5470]] (154-0478-00 standard), 10 kV acceleration, 6x10 cm viewing area }} | |||
{{Spec | Calibrator | ~1 kHz, 200 μV<sub>p-p</sub> to 100 V<sub>p-p</sub> }} | |||
{{Spec | Power | 90-136 V or 180-272 V, selected via primary voltage selector (inside cabinet) and voltage range selector (on rear panel), 50/60/400 Hz, 510 W, AC Fan }} | |||
{{EndSpecs}} | |||
==Internals== | ==Internals== | ||
===Triggering=== | ===Triggering=== | ||
The 'A' and 'B' triggers are based on a 10 mA [[tunnel diodes|tunnel diode]]. | |||
The 'A' | |||
Up to serial number 11889, it uses a [[TD253]]. | Up to serial number 11889, it uses a [[TD253]]. | ||
From 11890 onward, it uses a [[152-0140-01]]. | From 11890 onward, it uses a [[152-0140-01]]. | ||
===HV Transformer=== | ===HV Transformer=== | ||
A common problem with 547s is the [[HV transformers|HV transformer]]. | A common problem with 547s is the [[HV transformers|HV transformer]]. | ||
Rather than potting the HV transformer in wax, as was done up to that point, | Rather than potting the HV transformer in wax, as was done up to that point, the [[120-0308-00|547's HV transformer]] was potted in epoxy. | ||
the 547's HV transformer was potted in epoxy. | Unfortunately, this epoxy turned out to absorb moisture over time, particularly when used in humid climates. | ||
Unfortunately, this epoxy turned out to absorb moisture over time, | |||
particularly when used in humid climates. | |||
The moisture causes increased losses in the transformer. | The moisture causes increased losses in the transformer. | ||
Excessive losses require the regulator to drive the [[6AU5]] input oscillator tube (V800) harder. | Excessive losses require the regulator to drive the [[6AU5]] input oscillator tube (V800) harder. | ||
Eventually, the drive circuit cannot supply enough power to keep the supply in regulation. | Eventually, the drive circuit cannot supply enough power to keep the supply in regulation. | ||
The usual solution is to scavenge a replacement transformer from another scope. | The usual solution is to scavenge a replacement transformer from another scope. | ||
As a labor of love, hobbyists have been known to rebuild the HV transformers. | As a labor of love, hobbyists have been known to rebuild the HV transformers. | ||
This is discussed from time to time on the Yahoo TekScopes forum. | This is discussed from time to time on the groups.io (formerly Yahoo) TekScopes forum. | ||
Bernie Schroder has found that the HV transformer degeneration can be slowed considerably by keeping the HV module cool and dry. | |||
The mod he was taught by [[Jim Willams]] involves replacing the [[5642]] tube rectifiers with NTE517 diodes to reduce the load on the regulator circuit by about 1 Watt by eliminating the filaments. | |||
However, this can force the regulator past its design limit and result in lack of regulation, until the transformer heats up and more power is required due to losses. | |||
After changing to semiconductor diodes, it will be seen that grid pin 7 of V814 will be about 0 volts (fully on, | |||
with no swing to regulate) in an attempt to force its anode (pin 6) to about +55 V, which is the screen input of the 6AU5 (pin 8). | |||
One way to remedy this is to replace the anode resistor coming off pin 6 of V814 (R803) from 56 kΩ to 82 kΩ. | |||
Doing so changes the grid voltage on pin 7 of V814 to a comfortable −0.8 V at switch-on. | |||
Again, this becomes more negative as the losses inside the transformer increase, but not by much if the transformer is healthy. | |||
A second path to thermal runaway on early serial numbers is C808, which resonates the transformer primary winding. Tek used a Sprague 160P DiFilm Black Beauty. In the 2020's, 160P's are exhibiting high Dissipation Factor when warm, enough to self-heat in this case. Replace with any modern capacitor. | |||
===Vertical Amplifier=== | ===Vertical Amplifier=== | ||
The 547 has a five-stage BJT vertical amplifier that is fully differential from the plug-in | The 547 has a five-stage BJT vertical amplifier that is fully differential from the plug-in connector to the CRT vertical deflection plates. | ||
connector to the CRT vertical deflection plates. | There is one tube in the vertical signal path, a [[12AT7]] acting as a unity-gain buffer between the plug-in connector and the vertical amplifier. | ||
a [[12AT7]] acting as a unity-gain buffer between the plug-in connector and the vertical amplifier. | |||
====Spoiler Switch==== | |||
The plug-in bay of the 547 has a "spoiler switch" that only enables the full bandwidth of the 547's vertical signal path | |||
when certain relatively modern plug-ins are used, such as the [[1A1]], [[1A2]], [[1A4]], and [[1A5]]. | |||
Those plug-ins have a small hole to the left of the plug-in to mainframe connector, so they can be fully inserted without pressing the spoiler switch. | |||
(Spectrum analyzer plug-in Types [[1L30]] and [[1L40]] have the hole too but for no reason since their vertical output is low frequency.) | |||
* [[Media:Spoiler switch rationale from Tek 547 544 546 tech instr and training.pdf|Spoiler switch explanation excerpted from Tek 547 544 546 Technical Instruction and Training]] | |||
* [[Media:Spoiler switch rationale from Tek 547 notes.pdf|Spoiler switch explanation excerpted from Tek 547 Notes]] | |||
====Delay Line==== | |||
There is a 170 nanosecond [[delay line]] between the first and second gain stages. | There is a 170 nanosecond [[delay line]] between the first and second gain stages. | ||
===Power Supply === | ===Power Supply === | ||
The 547's power supply provides regulated outputs of −150 V, +100 V, +225 V, +350 V, | The 547's power supply provides regulated outputs of −150 V, +100 V, +225 V, and +350 V, plus a +325 V unregulated output for the CRT HV oscillator. | ||
Multiple secondary windings | Multiple secondary windings feed diodes for rectification for different voltages, using both center-tap and bridge configurations. | ||
The regulator section uses no transistors, only tubes. There are multiple 6.3 V secondary outputs for heaters, some elevated to different voltage levels | |||
based on the section/tube that is supplied, in order to keep the heater-to-cathode voltage level within limits. | |||
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 | 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 [[OG3]] VR tube. | |||
A [[12AX7]] is used as the comparator and two [[6CW5]] in parallel are used as series pass tubes. | |||
A [[6AU6]] is used as an error amplifier. | |||
Most other power supply sections in the 547 replicate the same basic design, except slight changes in tubes used: | |||
The +225 V and +100 V regulators employ a [[6080]] as the pass element, and +350 uses a [[6CW5]]. | |||
The plate voltage delay circuit is | The plate voltage delay circuit is similar to that found in many may other Tek scopes of the same era. | ||
Heater voltage is applied to all tubes immediately when the power switch is turned on. | |||
A [[6N030T|6N030T delay tube (P/N 148-0021-00)]] controls a relay that switches plate supply voltages on only after the tubes are warmed up. | |||
==Links== | ==Links== | ||
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* [http://www.ebay.com/gds/The-Tektronix-547-Oscilloscope-Magic-in-the-Box-/10000000000725321/g.html The Tektronix 547 Oscilloscope - Magic in the Box] | * [http://www.ebay.com/gds/The-Tektronix-547-Oscilloscope-Magic-in-the-Box-/10000000000725321/g.html The Tektronix 547 Oscilloscope - Magic in the Box] | ||
* [http://www.thevalvepage.com/testeq/tek/547/547.htm J.Evans's 547 page] | * [http://www.thevalvepage.com/testeq/tek/547/547.htm J.Evans's 547 page] | ||
==Common Problems== | |||
* See [[547/Repairs]] | |||
==Pictures== | ==Pictures== | ||
===547=== | |||
<gallery> | <gallery> | ||
Tek 547 1a2 new.jpg | Tek 547 trace.jpg | 547 with [[1A2]] | ||
Tek 547 1a2 new.jpg|547 with [[1A2]] | |||
Tek 547.jpg|Front view | Tek 547.jpg|Front view | ||
Tek 547 eng.jpg|547 serial "ENG B 23" | |||
Tek 547 eng2.jpg|547 serial "ENG B 23" | |||
Tek | |||
Tek | |||
Tek 547 ampex front.jpg | Tek 547 ampex front.jpg | ||
Tek 547 | Tek_547_Delayed_Trigger1.JPG | Tek 547 Delayed Trigger & ALT Sweep | ||
Tek 547 | Tek_547_Delayed_Trigger2.jpg | Tek 547 Delayed Trigger & ALT Sweep | ||
Tek 547 trace two sine.jpg|547 trace | |||
Tek 547 1a1 front.jpg|547 with [[1A1]] | |||
Tek_547_4-Trace.jpg | 547 with 1A2 in ALT Sweep Mode | |||
Tek_547_Delayed_Trig.jpg | 547 Delayed Trace | |||
Tek 547 ampex right external.jpg | Tek 547 ampex right external.jpg | ||
Tek 547 ampex rear.jpg | Tek 547 ampex rear.jpg | ||
Grey face 547.jpg|Gray 547 | Grey face 547.jpg|Gray 547 | ||
Tek 547 rear close.jpg | Tek 547 rear close.jpg | ||
Tek 547 rear connections.jpg|rear connections | Tek 547 rear connections.jpg|rear connections | ||
Tek_547_Vert_Amp.jpg | Tek 547 Vertical Amplifier | </gallery> | ||
===547 Internals=== | |||
<gallery> | |||
Tek_547-Top.jpeg | Internals - Top | |||
Tek_547-RHS-TBOpen.jpeg | Internals - RHS | |||
Tek_547-RHS.jpeg | Internals - Time Base - RHS | |||
Tek_547-Internal-LHS.jpeg | Internals - LHS | |||
Tek_547-Internal-Bottom.jpeg | Internals - Bottom | |||
Tek_547_HVSection-NoCover.jpg | Tek 547 HV Section and [[5642]]HV Rectifier Tube (Cover removed) | |||
Tek_547_HV_Diodes.jpg | Solid State HV Diode Mod | |||
Tek_547-TunnelDiodes-Trigger.jpg | Tunnel Diodes TD253 and TD3A in a Tek 547 Trigger/ Sweep Section | |||
Tunnel_DIode_1D2_2.2mA.jpg | 2.2 mA Tunnel Diode in 547 Delay Pickoff | |||
Tek_547_Vert_Amp.jpg | Tek 547 Vertical Amplifier. The output transistors are mounted on [[beryllium oxide]] discs. | |||
547_01.JPG|Top | |||
547_02.JPG|Right | |||
547_03.JPG|Left | |||
Tek_547_CRT1.jpg | Tek 547 CRT | Tek_547_CRT1.jpg | Tek 547 CRT | ||
Tek_547_CRT2.jpg | Tek 547 CRT Side View | Tek_547_CRT2.jpg | Tek 547 CRT Side View | ||
Tek_547_CRT_Def_Plates1.jpg | Tek 547 CRT Deflection Plates & Assembly | Tek_547_CRT_Def_Plates1.jpg | Tek 547 CRT Deflection Plates & Assembly | ||
Tek_547_CRT_Def_Plates2.jpg | Tek 547 CRT Electron Gun Assembly | Tek_547_CRT_Def_Plates2.jpg | Tek 547 CRT Electron Gun Assembly | ||
Tek_547_Chassis_Without_CRT.jpg | Tek 547 Chassis Without CRT and Plug in | Tek_547_Chassis_Without_CRT.jpg | Tek 547 Chassis Without CRT and Plug in | ||
Tek_547_Screen.jpg | Tek 547 Screen Scale | Tek_547_Screen.jpg | Tek 547 Screen Scale | ||
Tek_547_Power-Transformer3.jpg | Tek 547 Main Transformer | Tek_547_Power-Transformer3.jpg | Tek 547 Main Transformer | ||
Tek_547_Power-Transformer2.jpg | Tek 547 Main Transformer | Tek_547_Power-Transformer2.jpg | Tek 547 Main Transformer | ||
Tek_547_Power-Transformer1.jpg | Tek 547 Main Transformer | Tek_547_Power-Transformer1.jpg | Tek 547 Main Transformer | ||
Tek_547_Tubes.jpg | Tek 547 Inside view with Power ON | Tek_547_Tubes.jpg | Tek 547 Inside view with Power ON | ||
Tek_547_Transformer.jpg | 547 LV Transformer Connections | Tek_547_Transformer.jpg | 547 LV Transformer Connections | ||
Tek_547_Inside_Tubes.jpg | Inside a Tek 547 | Tek_547_Inside_Tubes.jpg | Inside a Tek 547 | ||
Tek 547 ampex right internal.jpg | |||
Tek 547 ampex left internal.jpg | |||
</gallery> | |||
=== RM 547=== | |||
<gallery> | |||
Tek rm547.jpg|RM547 | |||
Tek rm547 trace.jpg | |||
Tektronix rm547.jpg | |||
</gallery> | |||
=== Schematics === | |||
<gallery> | |||
Tek-547-trigger a.png|Trigger A | |||
Tek-547 vert amp2.png|Vertical amplifier | |||
</gallery> | </gallery> | ||
==Components== | |||
{{Parts|547}} | |||
[[Category:500 series scopes]] | [[Category:500 series scopes]] |
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