39,721
edits
5B40: Difference between revisions
Jump to navigation
Jump to search
m
no edit summary
mNo edit summary |
mNo edit summary |
||
| Line 17: | Line 17: | ||
==Internals== | ==Internals== | ||
The trigger signal passes through source switching, coupling switching, and then a JFET source-follower buffer. | The trigger signal passes through source switching, coupling switching, and then a JFET source-follower buffer. | ||
Next, the signal is buffered by a PNP emitter-follower biased at around | Next, the signal is buffered by a PNP emitter-follower biased at around 5 mA collector current. | ||
That provides a known (low) source impedance for driving the switch-selectable LF reject and HF reject filters. | That provides a known (low) source impedance for driving the switch-selectable LF reject and HF reject filters. | ||
The output of the filters drives a discrete NPN differential amplifier, which drives U165, a [[155-0109-01]] Tek-made trigger IC. | The output of the filters drives a discrete NPN differential amplifier, which drives U165, a [[155-0109-01]] Tek-made trigger IC. | ||