7A26: Difference between revisions

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|type=7A26  
|type=7A26  
|summary=200 MHz dual-channel amplifier  
|summary=200 MHz dual-channel amplifier  
|image=Tek 7a26 front_lc.jpg  
|image=Tek 7a26 front.jpg  
|caption=7A26 front panel  
|caption=7A26 front panel  
|introduced=1974
|introduced=1974
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{{Spec | Bandwidth |200 MHz}}
{{Spec | Bandwidth |200 MHz}}
{{Spec | Deflection | 5 mV/Div – 5 V/Div in 1−2−5 sequence }}
{{Spec | Deflection | 5 mV/Div – 5 V/Div in 1−2−5 sequence }}
{{Spec | Input impedance | 1 MΩ // 22 pF }}
{{Spec | Input impedance | 1 MΩ in parallel with 20pF±0.5pF SN B208879-below and 22pF±0.5pF SN B208880-up }}
{{Spec | Features | Bandwidth limiting switch (20 MHz) }}
{{Spec | Features | Bandwidth limiting switch (20 MHz) }}
{{EndSpecs}}
{{EndSpecs}}
==Links==
* [https://vintagetek.org/100000-7a26-plug-in/ Tom Rousseau's Golden 100,000<sup>th</sup> 7A26]
* [http://www.amplifier.cd/Test_Equipment/Tektronix/Tektronix_7000_series_amplifier/amplifier_7A26.htm Tek 7A26] @ amplifier.cd
* [https://www.youtube.com/watch?v=7scgCL_Rl6E Tektronix 7A26 Restoration and Alignment] by Zenwizard Studios @ YouTube
{{Documents|Link=7A26}}
{{PatentLinks|7A26}}


==Internals==
==Internals==
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The 7A26 does not use the ±50 V supplies provided by the mainframe.
The 7A26 does not use the ±50 V supplies provided by the mainframe.
==Repair issues==
The pins of the attenuator modules are connected to conductive traces on the ceramic substrate inside by low-temperature soldering, which can go bad.
Re-seating the module can temporarily restore the internal contact but will usually not fix the problem permanently.
Repair is possible by opening the click-locked lid and carefully re-soldering (see [[307-1012-00]]).
==Links==
* [https://vintagetek.org/100000-7a26-plug-in/ Tom Rousseau's Golden 100,000<sup>th</sup> 7A26]
* [http://www.amplifier.cd/Test_Equipment/Tektronix/Tektronix_7000_series_amplifier/amplifier_7A26.htm Tek 7A26] @ amplifier.cd
* [http://www.barrytech.com/tektronix/tek7000/tek7a26.html Tek 7A26] @ barrytech.com
* [https://www.youtube.com/watch?v=7scgCL_Rl6E Tektronix 7A26 Restoration and Alignment] by Zenwizard Studios @ YouTube


==Pictures==
==Pictures==


<gallery>
<gallery>
Tek 7a26 front.jpg    | Front panel
Tek 7a26 front_lc.jpg | Front panel
Tek 7a26 front_lc.jpg | Front panel
Tek-7a26-left.jpg    | left side
Tek-7a26-left.jpg    | left side

Latest revision as of 16:04, 11 October 2024

Tektronix 7A26
200 MHz dual-channel amplifier
7A26 front panel

Compatible with 7000-series scopes

Produced from 1974 to 1991

Manuals
Manuals – Specifications – Links – Pictures

The Tektronix 7A26 is a 200 MHz dual-trace vertical plug-in for 7000-series scopes. Designed by Tom Rousseau, it was the most successful 7000 series plug-in, with over 120,000 units produced.

The 75 MHz 7A18 and 400 MHz 7A24 share the same front panel layout and operation.

Key Specifications

Bandwidth 200 MHz
Deflection 5 mV/Div – 5 V/Div in 1−2−5 sequence
Input impedance 1 MΩ in parallel with 20pF±0.5pF SN B208879-below and 22pF±0.5pF SN B208880-up
Features Bandwidth limiting switch (20 MHz)

Links

Documents Referencing 7A26

(no results)

Patents that may apply to 7A26

Page Title Inventors Filing date Grant date Links
Patent US 3562464A Cam actuated switch having movable and fixed contacts on circuit board Howard Vollum • Willem H Verhoef • Tony Sprando 1968-10-07 1971-02-09 Cam switches • 2101 • 2701 • 2703 • 432 • 434 • 465 • 475 • 5A15N • 5A18N • 5A20N • 5A21N • 5A38 • 5A45 • 5B10N • 5B12N • 7A15 • 7A16A • 7A18 • 7A19 • 7A24 • 7A26 • 7B10 • 7B15 • 7B50 • 7B51 • 7B52 • 7B53A • 7B50A • 7B70 • 7B71 • 7B80 • 7B85 • 7B87 • 7B92 • 7B92A • 7D01 • 7D12 • 7D15 • 7J20 • 7S12 • 7T11 • 7T11A • AF501 • AM502 • AM503 • DC502 • DC503 • DC504 • DC505 • DM501 • DM502 • FG501 • FG501A • FG502 • FG503 • FG504 • FG507 • PG501 • PG502 • PG505 • PG506 • PG506A • PG508 • TG501 • SC502 • SC503 • SC504
Patent US 3719788A Switch having ganged contacts mounted on opposite sides of circuit board Ken Holland • Tony Sprando 1971-02-04 1973-03-06 465 • 475 • 5A38 • 5A45 • 7A15 • 7A16A • 7A18 • 7A19 • 7A24 • 7A26 • 7D15 • PG506
Patent US 3753170A Step attenuator apparatus having attenuator stages selectively connected in cascade by cam actuated switches Ken Holland 1971-02-10 1973-08-14 465 • 475 • 5A38 • 5A45 • 7A15 • 7A16A • 7A18 • 7A19 • 7A24 • 7A26
Patent US 3900711A Electrical contactor assembly for high frequency applications Ken Holland 1974-02-04 1975-08-19 465 • 475 • 5A38 • 5A45 • 7A15 • 7A16A • 7A18 • 7A19 • 7A24 • 7A26 • 7D15 • AM503

Internals

Controls layout and internal construction is very similar to the 75 MHz 7A18. Whereas the 7A18 is a discrete design, the 7A26 uses Tek-made differential amplifier ICs 155-0078-xx.

The 7A26 does not use the ±50 V supplies provided by the mainframe.

Pictures

Components

Some Parts Used in the 7A26

Part Part Number(s) Class Description Used in
151-1032-00 151-1032-00 Discrete component dual n-channel JFET (selected) 7A15A • 7A26
155-0078-00 155-0078-xx • 155-0273-00 • 155-0274-00 Monolithic integrated circuit broadband amplifier 464 • 465 • 466 • 468 • 475 • 475A • 475M • 485 • 7834 • 7844 • 7854 • 7904 • R7903 • R7912 • 7912AD • 7912HB • 7104 • 7A16A • 7A16P • 7A24 • 7A26 • 7A42 • 067-0587-01 • 067-0680-00 • AM503 • PG502 • PG508 • DC510 • DC5010 • FG5010
307-1012-00 307-1012-00 Discrete component thick-film 5x attenuator 7A26
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