I did some searching and found that in fact they do. Check this out it is interesting: http://home.pacbell.net/mtom168/antenna/
I have had a booster for years. with my old digital phone I just replaced, it made a big difference. But with my v551 I noticed no difference . that not to say I removed it yet but I still had dropouts while talking . I have a short time ago purchased a small extendable antenna from the bay and did notice one more bar as soon as installed.
