Expanding the signaling, again.

Over the past few weeks I have been working on the signaling on the layout.  First to correct some problems I've had in one of the signal blocks, and then to expand the signaling to the upper helix. The signaling on this layout is just red / green aspects with the actual signals being something I have scratch built myself.  Below are links to some of the earlier posts I have made on the signaling.

July 2021 - Expanding the signaling

July 2020 - My home made searchlight signals

May 2020 - First working signals on the layout

So the first step was to correct a problem I have been having with sensitivity on the Southern Pacific line in the 3rd signal block which includes the Carlin yard.  The NCE detectors I have been using don't have any sensitivity adjustment so I picked up a circuit from Azatrax that does have a sensitivity adjustment to see if that would make a difference.  After installing it, I was able to adjust it to get the results I wanted.  A nice thing about this Azatrax circuit was that the double pole relays were included on the board so I did not have to make up a relay board like I have been doing for the NCE sensors.

The sensors and relay board that had been removed from the 3rd signal block location was installed to provide detection for the upper helix which has become the 4th signal block.  They works fine there, I think because the track arrangement is simpler.

At the top of the upper helix the occupancy for each track is indicated with bi-color LED's that were added to the upper return loop control panel.

At the bottom of the upper helix near the east end of the Carlin yard, a pair of signals indicate the occupancy within the helix.

At the west end of the Carlin yard where the crossover leads to the WP track, another signal is connected to the WP signal block.  In the future I would like to have the signal only be green if the block is clear and the turnout is aligned for the crossover.