Push pull output stages can use triodes for lowest Z out and best linearity, but often use tetrodes or pentodes which give greater gain and power.
42.
The 954 and 956 types are sharp and remote cut-off pentodes, respectively, all with indirect 6.3 V, 150 mA heaters.
43.
The former was quickly superseded by the rf pentode, while the latter was initially developed as an alternative to the pentode as an audio power amplifying device.
44.
The former was quickly superseded by the rf pentode, while the latter was initially developed as an alternative to the pentode as an audio power amplifying device.
45.
Other tubes with multiple grids beside the pentode, such as the hexode and pentagrid converter tube, have been be used to make similar negative transconductance oscillators.
46.
Another similar, but not identical, amplifier pentode with a miniature 9-Pin base, ( B9A ), used in consumer electronics was the 6M5.
47.
The "'EF86 "'is a high transconductance sharp cutoff pentode vacuum tube with Noval ( B9A ) base for audio-frequency applications.
48.
It was developed during the introduction of TV and FM radio and delivered an output voltage large enough to directly drive an end pentode while still allowing for some negative feedback.
49.
The longest recorded valve life was earned by a Mazda AC / P pentode valve ( serial No . 4418 ) in operation at the BBC's main Northern Ireland transmitter at Lisnagarvey.
50.
However, Vox did not retain the pentode / triode output section modes from the " G1 " version that allowed for full or half power operation as well as a broader tonal palette.
