Here is a photo of a 1920s Clarodyne Radio sign recently purchased from the Indiana Historic Radio Museum by eBay seller radios10467. He has allowed me to use any of his pictures.
I know it doesn't difinitively prove - one way or the other - that Clarodyne was a manufacturer but it does show their trademark.
I believe the Indiana Historic Radio Museum is at this site:
- Clarodyne Radio Sign (50 KB)