Difference between revisions of "221"

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drives the top deflection plate and the other drives the bottom plate.
 
drives the top deflection plate and the other drives the bottom plate.
  
A version made for IBM has a single-sweep function not found on the standard 221.  
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MOD 290A is found on a version made for IBM, which adds a Single Sweep function, and a "Property of IBM" engraving.
  
 
==Pictures==
 
==Pictures==
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221-2.jpg|221 on top of 565
 
221-2.jpg|221 on top of 565
 
Tek 221 trace2.jpg
 
Tek 221 trace2.jpg
221 IBM Version.jpg|IBM Variant
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221 IBM Version.jpg| MOD 290A variant for IBM
221 Single_Sweep.jpg| Single Sweep Option
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221 Single_Sweep.jpg| MOD 290A variant for IBM
 
</gallery>
 
</gallery>
  
 
[[Category:200 series scopes]]
 
[[Category:200 series scopes]]

Latest revision as of 17:25, 14 June 2019

Manuals – Specifications – Links – Pictures

The Tektronix Type 221 is a miniature 5 MHz analog scope introduced in 1973.

Specifications

please add

Internals

The 221 has a switching power supply and built-in rechargeable batteries (which are a maintenance issue). It has a transformer-coupled trigger circuit which would seem to preclude DC level-based triggering. The trigger circuit uses a 1N3713 1 mA tunnel diode. The vertical output amplifier that drives the CRT plates is two opamps made from discrete transistors. One drives the top deflection plate and the other drives the bottom plate.

MOD 290A is found on a version made for IBM, which adds a Single Sweep function, and a "Property of IBM" engraving.

Pictures