Discrete Transistor VCA
A Voltage-Controlled Amplifier (VCA) made from three BC549 NPN transistors and three BC214 PNP transistors. It's a Gm Cell with variable current followed by a simple op-amp.
The four traces shown on the Tek 5440 are the input (1kHz), the two intermediate signals and the output. The control or modulation voltage was a triangle wave in this case.
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Uploaded on February 15, 2021
Taken on February 15, 2021
Discrete Transistor VCA
A Voltage-Controlled Amplifier (VCA) made from three BC549 NPN transistors and three BC214 PNP transistors. It's a Gm Cell with variable current followed by a simple op-amp.
The four traces shown on the Tek 5440 are the input (1kHz), the two intermediate signals and the output. The control or modulation voltage was a triangle wave in this case.
515
views
2
faves
1
comment
Uploaded on February 15, 2021
Taken on February 15, 2021