During the Southeast Asia War, the Department of Defense sought to limit the amount of information having possible intelligence value that could be gathered by enemy intercept teams. Long range HF (high frequency) radio communications were known to have been monitored and short range VHF (very high frequency) and UHF (ultra high frequency) communications had not only been monitored, but also had been intruded upon; that is, false information had been passed by the enemy. The need for better transmission security to protect military operations had become so important that Headquarters USAF asked the Air Force Security Service to provide the means for improving that security.
The Air Force Communications Security Center at Kelly Air Force Base, Texas, as the Air Force Security Service's experts, took on the task with assistance from the 6906th Electronic Security Squadron located at Brooks Air Force Base, Texas. The result was the development of the air transportable AN/MSR-1 Communications Intercept Van for monitoring friendly communications. Its purpose was to determine if sensitive military information was being inadvertently divulged in radio transmissions. If so, improved communications security procedures then could be quickly established.
In addition to its capability of monitoring HF, VHF and UHF radio transmissions, the AN/MSR-1 could monitor microwave communications as well. This last capability was useful in keeping a watch over Department of Defense microwave communications that might be vulnerable to interception by hostile forces. The fully-equipped van had four racks of equipment, and two racks containing three radios (one HF, one VHF and one UHF). The microwave rack consisted of monitor equipment and 12 cassette recorders, which were later removed because of operational restrictions.
The AN/MSR-1 van had several qualities that "endeared" it to those who used it. It was said that "... in the winter you could use it to store popsicles and in the summer you could fry eggs in it." Furthermore, individuals taller than 5-feet-8-inches tall either had to bend over or sit down. When the van was in transit, it would lean precariously when rounding corners.
The van monitored air-to-air, air-to-ground and intrabase radio communications during operational readiness exercises and inspections, training exercises and contingency support operations. During its 10 years of service it has been to all corners of the globe. It was operated in deserts, jungles, forests and cities, and has been subjected to snow, monsoon rains and typhoons. Whatever the environment, the "Misery" served well in fulfilling its missions.
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