
By Robert Stephens, US Army Signals
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Teletypes and Officers
We had multichannel systems going to various points, including two between us and Tan Son Nhut Airbase. We also had a system between the hill and the Australian Task Force at Nui Dat. We had a team there to operate a AN/MRC-69 terminal. We had a large number of telephone and teletype circuits going to various places, some terminating, some just patched through us to and from other places. We had one teletype circuit which was patched through to the Australian area. That circuit was one belonging to the Radio Research Units (RRU). That was the name all Army Security Agency units used in Vietnam, for unknown reasons. Regardless of what name they went by, their circuits always had high priority and were guaranteed to be trouble if they were not kept working properly. That particular circuit was a sixty-words-per-minutes (60 wpm), four wire, full duplex circuit from their headquarters at Bien Hoa. As with all their circuits it was fully secured, with all traffic encoded.
For example, in the summer of 1967 we received a report that the circuit was out. Bien Hoa RRU had already gone "lowers," that is they had taken their crypto equipment off-line, making it a regular teleytpe circuit so the signal people along the way could check the working. As long as they had been encoded all we could receive was scrambled teletype. Bien Hoa had not only gone lowers, they had put a "RY" test tape on. That involved a short loop of punched-paper tape which would send a steady stream of the letters RYRYRYRY, etc, which was the standard teletype testing and adjusting signal. Bien Hoa RRU was good at helping because they realized their circuit could not be restored without such help. The RRU people at Nui Dat, by contrast, always refused to go lowers. I checked our reception of the Bien Hoa transmission and we were receiving perfect RYs. We did not have any distortion testing equipment but both Long Bien and Tan Son Nhut did and they both reported the signal well within distortion limits. As the terminal people would not go off-line, the next best thing we could do was have our people at Nui Dat put a "loop-back" on the circuit, feeding the signal coming from Bien Hoa back to them, thereby testing everything on the circuit path except the terminal equipment at Nui Dat. Bien Hoa reported the signal was coming back perfect.
The circuit was out for a full three days before we finally managed to get one of our repairmen into the RRU shelter. The S3 major and company commander, in those three days, had spent much time on the hill, flat out telling me the trouble had to be at our site and we were going to be in big trouble if it was not corrected. They were both, along with our poor lieutenant who knew little about what we were talking about, continued to jump on us, especially me, as I was doing most of the testing and reporting. I had even drawn up a paper diagram of the circuit in order to explain why the trouble could be no place except in the terminal equipment but the major did not care to look at anything or hear anything other than an outage completion report.
Robert Stephens TH-5/TG Telegraph terminal, Frequency-shift keying, Used with standard tetetype machines, Vacuum tube based, Mark 1325 Hz, Space 1225 Hz, 20 Ma loop, Maximum speed 100 WPM (75 Baud), 115 VAC, 50-60 Hz, 65 W, Worked with 4-wire (full duplex) or 2-wire (half duplex) circuits, 15 Lbs, TM 11-5805-246-10.Comment: This circuit was most likely connecting to the Australian Unit '547 Signal Troop' who role was Signals Electronic Warfare (EW) and worked with the US Army Radio Research Units (RRU).
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The Memory Of Alfie
One of our men had a little puppy which
he named Alfie, a lively little thing, hard to keep up with. One night
when things were slow several of us were standing around in front of the
site. Our building had a sandbag wall around it, with the entrance
blocked by a section of wall, offset so that there were two sides to go
around in order to enter. Alfie was with us but all at once he took
off around the blast wall and ran into the building, with his owner
close behind yelling, "Damn it, Alfie! Come back
here!" We told him what had happened and he had a good laugh. He said he had been holding the laughter inside, trying to keep from laughing out loud in the lieutenant's face. LT Davidson had entered the office, sat down at his desk, and after a long pause had said, "Sergeant, these people have no respect for officers." He had been so serious, both in tone and look, that Dixon had to control himself until he could get outside.
Robert Stephens |
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