The DD/207 or DD.207 is a double diode with common filament. It has a very low filament power and can only be designed for signal applications. The DD/207 was introduced by Mazda in 1937 and the metalised paint screening is typical of the period.![](../pics/ach0024a.jpg)
The whole of the glass is covered in the zing loaded screening paint.The classic envelope is 40 mm in diameter, and excluding the B4 base pins is 89 mm tall.References: Data-sheet, 1040 & 1043. Type DD207 was first introduced in 1937. See also 1937 adverts. |
Pin Connections
| 1 | 2 | 3 | 4 | ![](../static/key.gif) a(2) | a(1) | f | f |
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Absolute Maximum Operating Conditions¶
| Vh | Ah | ![](../static/pdflogo.gif)
| 2.0 | 0.075 |
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Updated September 26, 2018.
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