221: Difference between revisions

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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.  
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
221 IBM Version.jpg| MOD 290A variant for IBM
221 Single_Sweep.jpg| Single Sweep Option
221 Single_Sweep.jpg| MOD 290A variant for IBM
</gallery>
</gallery>


[[Category:200 series scopes]]
[[Category:200 series scopes]]

Revision as of 18:25, 14 June 2019

{{{manufacturer}}} 
5 MHz miniature analog scope
Tektronix 221

Produced from 1975 to 1991

Manuals
Manuals – Specifications – Links – Pictures

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

Key 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