Doing some testing on the phones with the SV-Intercom and the SV-COM it appeared to have very poor reception, and lots of static. Tried a number of changes, swapped coax, and fabricated a 12x12 'ground plane' for antenna. Found that operating both intercom and radio together 'seemed' to be a factor. Removed the intercom from the config and then tried repositioning the antenna.
Big improvement when the antenna was temporarily 'mounted' under the HS, which was in a wall rack about 7 ft above the floor.