This device is used to better couple the TMCC and Legacy base output to the railroad. It improves coupling to the track, cleans up the track signal, and filters out other frequencies that are picked up by the track because it acts like a giant antenna. It also boosts the signal. Including me ( as the designer ) there have been two other railroad clubs that have built this device. All of us were experiencing signal loss and blinking lights and engines flipping out of command control because of loss of signal. We had all tried all of the other TMCC fixes such as ground planes and the like. Nothing worked to the point where TMCC was not working at all and our railroads were unusable. This device solved all our problems. It is not for the faint of heart. I am an electrical engineer and grew up with vacuum tubes and ham radio. This is a 3 watt linear amplifier using 2 vacuum tubes and a custom wound coil for the output tank circuit. Some have suggested converting it to solid state but I am not a solid state amplifier designer. Another person will have to tread that road. In the mean time this works and has saved my railroad and 2 others that I know about. Note the aluminum plate between the 6AQ5 tube and the coil. I was using an existing chassis from another project and I felt the tube was to close to the coil for a remote possibility of heat and capacitance coupling. No basis for that other than a feel. Mounting the 6AQ5 and the coil further apart would have made me not even think of a shield. I buy most of my tubes and transformers and capacitors from www.tubesandmore.com. I buy a lot of other stuff like resistors and fuse holder from Mouser. Parts should not be a problem. I actually had all of this stuff in my parts bins but I am 64 and have been in the electronics game since I was 5 years old. The tank coil is wound on a piece of 1 inch PVC pipe using 28 gauge enameled magnet wire. The primary with the most turns is wound first in a single layer. Drill a small hole to stuff the starting end through and start winding in close spaced single layer until done. Then you wrap the whole thing with electrical tape, about 2 layers of Skotch 33, and then wind the secondary over the tape starting at the same end and winding in the same direction. You will have a much shorter winding for the secondary. The primary and secondary ends that start even with each other will be the plate wire and the track wire respectively. The other primary end is the B+ and the other secondary end is ground. You must use a grounded power cord and ground the metal chassis and this secondary wire also. You can add more turns to the secondary to increase the output. I believe one club did that.
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