112: Difference between revisions

Jump to navigation Jump to search
17 bytes added ,  10 October 2021
no edit summary
No edit summary
No edit summary
Line 27: Line 27:
The output terminals of the 112 are on the right side in the rear, so the 112 can sit to the left of an oscilloscope
The output terminals of the 112 are on the right side in the rear, so the 112 can sit to the left of an oscilloscope
and short wires can connect the 112 to the oscilloscope's CRT.
and short wires can connect the 112 to the oscilloscope's CRT.
A two-position switch on the rear panel of the Type 112 controls the common-mode output voltage.
A two-position switch on the rear panel of the Type 112 controls the common-mode output voltage.
In one position, the common-mode output voltage is +150 V,
In one position, the common-mode output voltage is +150 V, which is the plate voltage of the [[6AG7]] tubes of the output amplifier.
which is the plate voltage of the [[6AG7]] tubes of the output amplifier.
In the other position, the common-mode output voltage is 0 V.
In the other position, the common-mode output voltage is 0 V.
The shifting of the common-mode output voltage 150 V downward is accomplished
 
by enabling a pair of 680 μA DC current sinks that cause a voltage drop on 220 kΩ series output resistors.
The shifting of the common-mode output voltage 150 V downward is accomplished by enabling a pair of 680 μA DC current sinks that cause a voltage drop on 220 kΩ series output resistors.
[[6CB6]] pentodes form the current sinks, with their cathodes tied to -150 V.
[[6CB6]] pentodes form the current sinks, with their cathodes tied to -150 V.
The 220 kΩ output resistors also provide short circuit protection.
The 220 kΩ output resistors also provide short circuit protection.
The Type 112 manual recommends 0 V for driving the CRT of the [[511]],
 
and +150 V for driving the CRT of the [[512]], [[513]], or [[514]].
The Type 112 manual recommends 0 V for driving the CRT of the [[511]], and +150 V for driving the CRT of the [[512]], [[513]], or [[514]].


==See Also==
==See Also==
Line 67: Line 67:
</gallery>
</gallery>


{{Parts|112}}


[[Category:Differential amplifiers]]
[[Category:Differential amplifiers]]

Navigation menu