With 8741 ft., Mount Irish is the tallest peak in the Pahranagat Range, overlooking most of Tikaboo Valley and the northern Nellis Ranges. This makes it a prime location for a radio repeater facility. And sure enough, there is quite a selection of radio antennas and microwave dishes along with several small buildings and trailers on the plateau on top. The slopes of Mt. Irish are very steep, and there is no road access to the top. Just like Bald Mountain, the fully automated and unmanned facility is serviced by helicopter. Unlike Bald Mountain, however, the top of Mount Irish is on public land. So, after studying various topo maps and satellite images to find the easiest way up, Gregos and I set out to explore the site on June 6, 2008. The easiest way up is still about two Tikaboos in terms of difficulty, and even with light packs the hike up took us a good 3 hours.
The electronics for the radio site are housed in four small buildings and storage containers. The cables from the antenna tower all lead into the largest of the buildings. The site is powered by two large solar panels. There are also a number of propane bottles next to one of the buildings. Possibly for a backup generator or for heating the buildings in winter. There is a level area just east of the buildings where a helicopter can land.
The view from the top of Mount Irish is spectacular. However, it does not have a view of Area 51. The only visible part of the Groom Lake Base is the explosives storage area and the engine test cells at the far south end of the base and the south end of the runway. The Groom Mountain Range obstructs the view of the main facility.
At one point Mt. Irish was a central hub for the original ACMI Range system used for the Red Flag exercises, which provides controllers at Nellis with exact 3-D position data on all airborne players. The old ACMI sites on Flat Top and on Badger Mountain were pointed to Mount Irish.
The original ACMI system has since been replaced with the newer Nellis Air Combat Training System (NACTS), with a central hub located on Highland Peak, near Pioche. But the Mount Irish facility still serves as one of 15 ground stations that are located around the ranges. A couple of microwave dishes, similar to the new dishes on Badger Mountain, are pointed to Highland Peak, and an omni-directional antenna provides the aircraft uplink. The new system operates on two frequencies in the 1.8 GHz range.
Contrary to common misconceptions, the large dish is NOT used for the Rachel phone system. It is also NOT linked to Bald Mountain. Instead, it is a microwave relay to Cedar Peak, connected to the various facilities within the NTTR, in particular TECR and TPECR. The microwave relay operates in the 7GHz range. The relay is likely linked to the NACTS system above. It also appears that there may be a linkup for IP-based mobile data terminals on the ground or in the air. We found a couple of antennas that may provide WiFi access.
The relay for the Rachel phone system is a passive reflector north of the peak. It bounces the signal from the Rachel transmitter on the north side of Tempiute Mountain to the phone company building in Alamo. It is listed in the FCC database as a passive repeater. And we found no evidence for any direct connection to Bald Mountain or to Area 51.
Other radio installations on Mount Irish include a repeater for the Lincoln County Sheriff (input: 154.070 and 155.535 MHz, output: 154.860 and 155.205 MHz) and a site of the NV Shared Trunking system. The output frequencies are 856.4625, 857.4625, 858.4625 and 859.4625 MHz, in that LCN order. There is also a smaller directional antenna that looks like 900 MHz, pointed north. We were not able to determine what that antenna is used for. And, another, much smaller site is located on a plateau about 0.8 miles north-east of Mount Irish. We currently have no information on that site.
The GPS coordinates of the top of Mount Irish are N37°38'41.0" / W115°24'5.4". There are at least four survey markers at the top. Three markers from the U.S. Coast & Geodetic Survey date back to 1944. The fourth marker of the Defense Mapping Agency is from 1985 (see photo below). This marker is similar to a marker found on Badger Mountain. It seems likely that 1985 is the year the original ACMI system was installed.