Hallo guys
I posted a thread about my project a few weeks back. I need to build a feedback elliminator for a PA system. I settled on a final design and I just want to know if my idea is feasable or not, and if there is any suggestions to do some part of the design in a other way.
1. The circuit will consist of a main microphone, low-pass filter, frequency to voltage converter(LM2907) and a voltage controlled amplifier(VCA).
2. The output signal of the microphone will be split in parallel to the input of a pre-amp and frequency to voltage converter.
3. The output signal of the microphone will go into a pre-amp, which output will than be inputted into a low-pass filter with a cut-off frequency of 15kHz. This output will than be amplified by the voltage control amplifier.
4. The frequency to voltage converter will convert the frequency of the output signal of the microphone to a voltage that will control the gain of the VCA. When a high voltage is outputted by the frequency to voltage converter, the gain of the VCA will be low.
- The way the feedback will be elliminated is to reduce the gain of the VCA when feedback occurs.
For the VCA I wanted to use a LMH6505 ic from national semi-conductors but this component is not available in Cape Town. Can you please suggest a electronic device to use in the place of that?
Thank you for helping me
I posted a thread about my project a few weeks back. I need to build a feedback elliminator for a PA system. I settled on a final design and I just want to know if my idea is feasable or not, and if there is any suggestions to do some part of the design in a other way.
1. The circuit will consist of a main microphone, low-pass filter, frequency to voltage converter(LM2907) and a voltage controlled amplifier(VCA).
2. The output signal of the microphone will be split in parallel to the input of a pre-amp and frequency to voltage converter.
3. The output signal of the microphone will go into a pre-amp, which output will than be inputted into a low-pass filter with a cut-off frequency of 15kHz. This output will than be amplified by the voltage control amplifier.
4. The frequency to voltage converter will convert the frequency of the output signal of the microphone to a voltage that will control the gain of the VCA. When a high voltage is outputted by the frequency to voltage converter, the gain of the VCA will be low.
- The way the feedback will be elliminated is to reduce the gain of the VCA when feedback occurs.
For the VCA I wanted to use a LMH6505 ic from national semi-conductors but this component is not available in Cape Town. Can you please suggest a electronic device to use in the place of that?
Thank you for helping me