The test was done by the communications team. Both units use the same LMR400 radio so in theory there should be no difference. With a LS with 1 watt of power being transmitted a RSSI of -43 dBm was observed with the internal antenna. With a LS+ a RSSI of -44dBM with the internal antenna was observed, so no significant difference.
I knew there was a difference early on in the LS+ with the radio needing the external antenna. That was also compounded by a radio issue with the T3 when it first came out. I was not sure of all of those issues have been resolved.
Although Matt J. attributed the test results to the Javad team in Armenia, he doesn't go into detail as to how they conducted their test(s). Is there a separate paper or other publication by the team doing the tests in Armenia describing in-depth which radio-to-antenna cables, ground plane discs, TX antenna(s), etc. were used in each of the radio tests. For example, were all tests completed using the same cable (14-578117-06) and a 2.4 dBd gain antenna (99-587309-01) without ground plane disc with the base of the broadcast antenna at a height of 2 meters and the LS HI at 1.5 meters? The photos included in July's radio workshop look like they were using a 5dBd gain UHF antenna with a ground plane disc at about 4 meters above the ground used for their 1-watt viewshed test, but likely not the same arrangement for received signal strength indicator table above. Without knowing the testing conditions, the stated expectations may possibly vary.