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(JFET conversion a la 1A7)
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* [http://w140.com/mmm/tek-w.pdf Tektronix Type W Manual (37MB, PDF)]
* [http://w140.com/mmm/tek-w.pdf Tektronix Type W Manual (37MB, PDF)]
* [[Media:070-432.pdf|Tektronix Type W Manual (11MB, PDF)]]
* [[Media:070-432.pdf|Tektronix Type W Manual (11MB, PDF)]]
* [[Media:070-432_Schematic_SN3270up.pdf|Tektronix Type W Schematics Color for SN 3270 up (10MB, PDF)]]
* [[Media:070-1109-00.pdf|Tektronix Type W SN 7000-up Manual (PDF, OCR)]]
* [http://w140.com/tek_type_w_schematics.pdf Tektronix Type W Schematics Only (PDF)]
* [http://w140.com/tek_type_w_schematics.pdf Tektronix Type W Schematics Only (PDF)]
* [[Media:Tek type w fcp jan 1969.pdf|Tektronix Type W Factory Calibration Procedure, January 1969 (PDF, needs OCR)]]
* [[Media:Tek type w fcp jan 1969.pdf|Tektronix Type W Factory Calibration Procedure, January 1969 (PDF, needs OCR)]]
* [[Media:Tek type w fcp no ocr.pdf|Tektronix Type W Factory Calibration Procedure, March 1969 (PDF, needs OCR)]]
* [[Media:Tek type w fcp no ocr.pdf|Tektronix Type W Factory Calibration Procedure, March 1969 (PDF, needs OCR)]]
* [[Media:Tek type w cal outline.pdf|Tektronix Type W Calibration Outline (PDF, OCR)]]
<!-- * [[Media:tek_type_w_schem_only.pdf|Tektronix Type W Schematics Only (PDF, OCR)]] -->
<!-- * [[Media:tek_type_w_schem_only.pdf|Tektronix Type W Schematics Only (PDF, OCR)]] -->
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faster than its [[Z|Type Z]] predecessor, and it extends performance in  
faster than its [[Z|Type Z]] predecessor, and it extends performance in  
terms of sensitivity, reaching 1 mV/div.  It achieves 20,000 to 1 common-mode  
terms of sensitivity, reaching 1 mV/div.  It achieves 20,000 to 1 common-mode  
rejection at DC and low frequencies.
rejection at DC and low frequencies.  It was designed by [[John Horn]].


Type W has two signal inputs, "A" and "B", and a built in precision variable voltage supply, "V<sub>C</sub>",  
Type W has two signal inputs, "A" and "B", and a built in precision variable voltage supply, "V<sub>C</sub>",  
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Type W is the only letter-series plug-in with an "infinite resistance" input mode selectable at the front panel.
Type W is the only letter-series plug-in with an "infinite resistance" input mode selectable at the front panel.
([[1A5|Type 1A5]] has an internal jumper that can be cut.)
(Types [[1A5]] and [[1A7]] have an internal jumper that can be cut.)


Original production uses a pair of type [[8056]] [[Nuvistor|Nuvistors]] in the front end; starting at serial number 7000 these were replaced with JFETs.
Early production Type W in a [[556]] mainframe won't
meet spec for overdrive recovery time, because an overdriven W
passes enough common-mode to the mainframe vertical amp to
saturate it.  At S/N 3270, this was fixed, by adding another stage to attenuate CM.
The new "output amp" circuit board clips onto the rear bulkhead;
significant hand mods are required on the chassis.
This was also offered as Modification kit 040-0447-00 to retrofit existing instruments.
   
   
Type W was created with a pair of type [[8056]] [[Nuvistor|Nuvistors]] in the front end.  In 1971 (S/N 7000), following the lead of Type [[1A7]], the Nuvistors were replaced by JFETs to reduce drift.  Mod kit 040-0590-00 was offered for existing instruments.
In the letter-series timeline of differential comparators, Type W, [[introduced in 1965]],  
In the letter-series timeline of differential comparators, Type W, [[introduced in 1965]],  
follows [[Z|Type Z]] and precedes [[1A5|Type 1A5]].
follows [[Z|Type Z]] and precedes [[1A5|Type 1A5]].
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Type_w_bottom.jpg|Bottom view.
Type_w_bottom.jpg|Bottom view.
Tek w block.png|Block Diagram
Tek w block.png|Block Diagram
Tek w differential comparator.png|Differential Comparator
Tek w differential comparator.png|Differential Comparator, initial version
Tek w input attenuators.png|Input Attenuators
Tek w input attenuators.png|Input Attenuators
Tek w switching diagram.png|Switching Diagram
Tek w switching diagram.png|Switching Diagram
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[[Category:500 series plugins]]
[[Category:500 series plugins]]
[[Category:Differential amplifiers]]

Revision as of 10:37, 18 June 2021

Template:Plugin Sidebar 2 The Tektronix Type W is a differential comparator plug-in amplifier for 500-series scopes. Its bandwidth varies from 23 MHz to 8 MHz depending on gain. Type W is faster than its Type Z predecessor, and it extends performance in terms of sensitivity, reaching 1 mV/div. It achieves 20,000 to 1 common-mode rejection at DC and low frequencies. It was designed by John Horn.

Type W has two signal inputs, "A" and "B", and a built in precision variable voltage supply, "VC", which is controlled by a ten-turn pot and can vary from either −1.1 V to +1.1 V or −11 V to +11 V. A mode switch selects between displaying A−VC, A−B, or VC−B. The "A−B" mode is particularly useful for displaying the current in a sense resistor, while the other modes provide "slideback" measurements of small variations superimposed on a large constant. An output of VC is provided on the front panel for precision measurements.

Unlike the Type Z, Type W has two gain axes: a decade attenuator and a 1−2−5−10−20−50 selector, reminiscent of Type D from ten years before.

Type W is the only letter-series plug-in with an "infinite resistance" input mode selectable at the front panel. (Types 1A5 and 1A7 have an internal jumper that can be cut.)

Early production Type W in a 556 mainframe won't meet spec for overdrive recovery time, because an overdriven W passes enough common-mode to the mainframe vertical amp to saturate it. At S/N 3270, this was fixed, by adding another stage to attenuate CM. The new "output amp" circuit board clips onto the rear bulkhead; significant hand mods are required on the chassis. This was also offered as Modification kit 040-0447-00 to retrofit existing instruments.

Type W was created with a pair of type 8056 Nuvistors in the front end. In 1971 (S/N 7000), following the lead of Type 1A7, the Nuvistors were replaced by JFETs to reduce drift. Mod kit 040-0590-00 was offered for existing instruments.

In the letter-series timeline of differential comparators, Type W, introduced in 1965, follows Type Z and precedes Type 1A5.

Specifications

please add

Pictures