Difference between revisions of "A"

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Customers were told to get Type [[B]] instead, although it cost more.
 
Customers were told to get Type [[B]] instead, although it cost more.
  
* http://bama.edebris.com/manuals/tek/a/
+
* [http://bama.edebris.com/manuals/tek/a/ Tektronix Type A Manual (PDF)]
* http://w140.com/tek_fcp/tek_type_a_factory_cal_proc.pdf
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* [http://w140.com/tek_fcp/tek_type_a_factory_cal_proc.pdf Tektronix Type A Factory Calibration Procedure (PDF)]
  
 
<gallery>
 
<gallery>
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53A 2.JPG|chassis
 
53A 2.JPG|chassis
 
53A 3.JPG|chassis bottom
 
53A 3.JPG|chassis bottom
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File:Tek type a schem.png|schematic
 
</gallery>
 
</gallery>

Revision as of 08:12, 25 August 2012

The Tektronix Type A is a single-channel preamp introduced in 1959 for 500-series scopes. It provides two inputs and has a switch to select between them. A 545 with a Type A has a system risetime of 18 nanoseconds and a bandwidth of 20MHz. The plug-in uses a 12AU6 in the front end as a cathode follower. This input stage drives the second stage, a differential amplifier made of two more 12AU6 tubes. The second stage drives the output stage, a pair of cathode followers made of both halves of a 12AT7 tube. The plate of each output tube is connected to the cathode of the other output tube by a 0.005 microfarad capacitor. This "cross-coupling" extends the high-frequency response.

Although 1959 was the first year one could find a "Type A" in the catalog, the same instrument with earlier "Type 53/54A" nomenclature was in the August 1956 Short Form catalog, and its slower Type 53A ancestor was in the August 1954 catalog which introduced the first 500-series scopes, the 531 and the 535. Type 53A has only three tubes, and a bandwidth of 10MHz in the 530 mainframes. Tek never documented its performance in the 540 mainframes.

Type A was the first letter-series plug-in to be discontinued, in 1962. Customers were told to get Type B instead, although it cost more.