Analog FM Modulator/Demodulator with NE/SE 546 IC

[kheirdoost]

Hi guys
I have been working with Ne/SE546 IC to make an analog FM modulator/demodulator.
The output of this IC as a modulator give a frequency modulated rectangular waveform. Is there a way that I can get sinusoidal modulated signal at the output other than filtering? I think we I need a way to change the VCO of this IC to a pure sinusoidal instead of rectangular oscillator.
My main problem with this IC is when I use this IC as a demodulator. When I modulate a 100 KH sinusoidal message with this IC and demodulate it, I receive a 100KHz rectangular waveform instead of sinusoidal waveform.
Since I am planning to use this IC as a wide band demodulator (3 MHz BW) I need to resolve this matter before going to higher bandwidths, I think.

 

[jiripolivka]

Most similar ICs generate rectangular pulses as their structure is composed of switches. The only reasonable way to clean the spectrum is to use filters, low-pass and band-pass. In a demodulator it does not matter I think.

 

[kheirdoost]

Most similar ICs generate rectangular pulses as their structure is composed of switches. The only reasonable way to clean the spectrum is to use filters, low-pass and band-pass. In a demodulator it does not matter I think.

Thanks jiripolivka.
I will let you know if more I found.