the GL Mk II. Operating at 5 m (60 MHz), Son-2a used separate trucks for the transmitting and receiving equipment, and a third truck carried a power generator. In use, a dipole-array transmitting antenna giving a broad pattern was fixed in position atop a grounded pole. Separated from the transmitter by about 100 meters, the receiving station was on a rotatable cabin with wing-like antennas mounted on each side. A mast above the cabin held a pair of antennas that were used with a goniometer for height-finding. Like the original British GL Mk II, the Son-2a was not of great assistance in directing searchlights and anti-aircraft guns. Nevertheless, it was put into production and released to the Red Army in December 1942. Over the next three years, about 125 of these sets were built. In addition, over 200 GL Mk IIIC systems (improvements over the Mk II and built in Canada) were provided under the Lend-Lease program, making the combination the most-used radar equipment in the Soviet Union during the war. Ukraine had been the third objective of the invading German Army. By late July 1941, their mechanized forces were approaching this region, and, following orders from the Defense Committee, the UIPT in Kharkov made evacuation preparations. For this, the LEMO was split from the UIPT, and the two organizations would be sent to different cities: Alma-Ata for the main operation and, separated by 1,500 km, Bukhara for the LEMO. While the preparations for moving were going on, the LEMO was directed to bring the experimental Zeni equipment to Moscow for testing by the NIIIS-KA. In mid-August, Usikov, Braude, and several other LEMO staff members went to Moscow, where they were attached to the NIIIS-KA. The Zenit system was installed in the Moscow outskirts, giving the opportunity for testing in combat. It was found that, while the accuracy of the system was not sufficient for precise aiming, it was satisfactory for barrage firing. It could also be used as a supplement to the RUS-2 surveillance system in guiding fighter aircraft. In September, the team made field modifications to the Zenit and more tests were run. It was found that the detection range had been doubled, but the dead zone increased by a like amount. The NIIIS-KA believed that the prospects were good for this to be developed into a suitable system, but laboratory conditions were necessary. Thus, the Zenit and