Diamond X50 question

[alternative3d]

Would anyone know if the Diamond X50 VHF/UHF base antenna needs to grounded in order to perform properly?. The reason I am asking is I have this antenna in the corner of the attic and run a Icom 2200H into it. This setup appears to work fine and I always get good reports but I was told that this antenna needs to be grounded otherwise the SWR could be to high and damage the radio. I am somewhat skeptical in accepting this as the antenna has a ground plane but just wanted some advise whether grounding is needed or not.
Thanks

 

[packrat]

Just check the swr, and if it is good, leave it alone.

PR

 

[W5LZ]

It does not require grounding.
- 'Doc

 

[Moleculo]

It only needs DC ground for lightning or other electrical surge protection. The ground plane radials provide the RF ground. You have yours in the attic, so a DC ground probably isn't really necessary unless you're worried about a nearby electrical circuit shorting on the antenna somehow.