15
edits
No edit summary |
m (missing whitespace) |
||
Line 58: | Line 58: | ||
==Internals== | ==Internals== | ||
The 221 has a switching power supply and built-in rechargeable batteries (which | 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. | 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 trigger circuit uses a [[1N3713]] 1 mA [[tunnel diode]]. |
edits