Just finished building what I hope is the "production" model. The completed unit consists of three pieces. Obviously, the actual buffer unit itself, a 24V 1A power brick, and an "earth ground" tap for the command base. The ground is tapped off the outside of the power barrel, this is the connection through the command base power brick to the 3rd wire on the plug. Connecting the buffer is dirt simple.
- Connect the earth ground tap between the command base power and the brick
- Connect the loose wire on the ground tap to the Earth GND terminal on the TMCC Buffer.
- Connect the track signal output wire from the command base to the Base INP terminal on the TMCC Buffer.
- Connect the Boost OUT terminal of the TMCC Buffer to the layout track connection.
The buffer is ready to go. Plug in the 24V power brick, power up the command base, and start running trains.
The three other connections to the buffer box are for DC meter measurements. You can read a relative level of both the BASE DC signal and the BOOST DC output signal referenced to the GND DC pin. These will possibly be useful in the future when we want to compare results between different layouts to evaluate the effects of capacitive loading on the buffer output. Note that these are optional outputs, they don't ever have to be used to effectively use the TMCC buffer. The circuitry that drives these also drives a signal level LED, red is very low or no base signal, off is marginal base signal, and green is a good base signal. I usage note, if there is nothing connected to the Base INP terminal, you may see the signal level indicated as green (good). This happens because stray AC is being fed to the buffer from the floating input, it only happens if there is no connection to the input.
This unit is going out for a real layout test, it'll be tested on the NJ-HR layout. Upon satisfactory test results there, I'll be ready to order parts for these. Stay tuned...