32,948
edits
No edit summary |
No edit summary |
||
Line 22: | Line 22: | ||
The fine steps between the deflection ranges are calibrated in 1% increments. | The fine steps between the deflection ranges are calibrated in 1% increments. | ||
The 11A32 | The 11A32 and the [[11A34]] use exactly the same firmware. | ||
Each of the 11A32’s two channels has its own M377 amplifier. | |||
and the | The display outputs of the two amplifiers are hard wired in parallel and drive the mainframe’s 50 Ω input impedance. | ||
The same is true of the trigger outputs of | The same is true of the trigger outputs of the two amplifiers. | ||
The version of the M377 used in the 11A32 has 100 Ω output impedance so that two of them in parallel create a source impedance of 50 Ω. | |||
Each M377 amplifier's nominal common-mode output voltage is zero whether enabled or not. | |||
When not enabled each M377 differential output is exactly zero by design. | |||
This fact is used during calibration by the plugin’s firmware to determine the mainframe’s imbalance and compensate for it during normal operation. | |||
See the block diagram below. | See the block diagram below. | ||