TN-342/WRT Navy Transmitting Antenna Tuner

The TN-342 is used for impedance matching the AN/WRT-2 HF transmitter to an antenna. It has a motor-driven inductor (RF autotransformer) plus a switch that will bypass the tuner or add some capacitors in series or parallel with the inductor.

TN-342 pages from the AN/WRT-2 manual - Download 13 MB pdf
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After initial hosing off
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This is cleaner than when we hauled it out of the weeds and dirt!
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Simple Green & Elbow Grease
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OK - clean enough to pull the case apart now
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Not bad inside
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Blower, Auto-transformer motor drive, Configuration switch motor drive
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Blower directs air to coil
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Main coil - an autotransformer with a shorting ring that moves under motor control

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Had to go inside here to get to several coax leads that were loose - and some 
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Cleaned up, but I still need to repair the pressure gauge (charged with 20 psi of dry nitrogen). The control connector is too corroded - will have to be replaced.
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Parts that were rattling around loose inside. The long machine screw is to hold down a couple of cable clamps - but I can't figure out how to get to them inside the main coil. I don't know what the 3/8-16 nut/washer goes to - can't find anything like that inside!