39,465
edits
221: Difference between revisions
Jump to navigation
Jump to search
no edit summary
mNo edit summary |
No edit summary |
||
| Line 33: | Line 33: | ||
a maintenance issue). It has a transformer-coupled trigger circuit which | a maintenance issue). It has a transformer-coupled trigger circuit which | ||
would seem to preclude DC level-based triggering. The trigger circuit uses a | would seem to preclude DC level-based triggering. The trigger circuit uses a | ||
[[1N3713]] 1 mA [[ | [[1N3713]] 1 mA [[tunnel diode]]. The vertical output amplifier | ||
that drives the CRT plates is two opamps made from discrete transistors. One | that drives the CRT plates is two opamps made from discrete transistors. | ||
drives the top deflection plate | One drives the top deflection plate, the other the bottom plate. | ||
The power supply in the 221 uses the [[120-0876-00]] transformer. | The power supply in the 221 uses the [[120-0876-00]] transformer. | ||
MOD 290A is | The 221 contains one integrated circuit, a 741 opamp that creates a virtual ground, otherwise only discrete (including dual) transistors. | ||
MOD 290A is a version of the 221 made for IBM, which adds a Single Sweep function, and a "Property of IBM" engraving. | |||
==Pictures== | ==Pictures== | ||
<gallery> | <gallery> | ||
Tek 221 1.jpg|Front | Tek 221 1.jpg|Front | ||