초록 ▼

The DC magnetization of a transformer core is prevented without increasing the size of an output transformer in a condenser microphone which is operated by a phantom power source, uses a vacuum tube as an impedance converter, and outputs a vacuum tube signal via the output transformer. The condenser

The DC magnetization of a transformer core is prevented without increasing the size of an output transformer in a condenser microphone which is operated by a phantom power source, uses a vacuum tube as an impedance converter, and outputs a vacuum tube signal via the output transformer. The condenser microphone includes a condenser microphone capsule MC, a vacuum tube V01 used as an impedance converter, and an output transformer TRS having a primary winding F connected to the plate and screen grid of the vacuum tube V01 and a secondary winding S connected to the phantom power source via an output connector, wherein the primary winding F has a center tap CF and both ends of the secondary winding S are connected to the center tap CF via constant current diodes D04 and D05, respectively.

대표청구항 ▼

The invention claimed is 1. A condenser microphone, comprising: a condenser microphone capsule, a vacuum tube used as an impedance converter, and an output transformer having a primary winding connected to a plate and a screen grid of the vacuum tube and a secondary winding connected to a phantom p

The invention claimed is 1. A condenser microphone, comprising: a condenser microphone capsule, a vacuum tube used as an impedance converter, and an output transformer having a primary winding connected to a plate and a screen grid of the vacuum tube and a secondary winding connected to a phantom power source via an output connector, the condenser microphone being operated by the phantom power source, wherein the primary winding has a center tap and both ends of the secondary winding are connected to the center tap via constant current diodes, respectively. 2. The condenser microphone according to claim 1, further comprising a voltage divider resistor connected to the screen grid to apply a predetermined voltage to the screen grid, wherein a relative difference between a current supplied from one end of the primary winding to the plate and a current supplied from the other end of the primary winding to the voltage divider resistor is 5% or less.