Why Do Double Balanced Modulators Discard the Information Component?

[fran1942]

Hello, we are learning about single balanced and double balanced modulators.
Apparently single balanced modulators include an information, upper and lower sideband component while double balanced modulators use only the upper and lower sideband components.
Can someone please tell me why the information component is discarded by double balanced modulators. How is that the information component is not necessary ?

Thanks for any help.

 

[marcusl]

You have it backwards: information is carried in the sidebands, while the carrier, which contains no information, is suppressed in a double balanced mixer.