Thursday, January 28, 2016

January Update

In January traditionally not much happens but this year I managed to do a few things on the Top Level Signal Controls, a few "Other things" and continued planning for the "Overseas Trip" too. So here is the unscheduled update.

Top Level Signal Controls

Components laid out ready for fixing.  I have include space for additional modules just in case I have not thought of something...  The ribbon cables at the bottom are to provide the "red" inputs to the 45 Three Light Signal Modules on the reverse side of the board. The ribbon cables were being glued to the board when the photo was taken.

Ribbon cables terminated and signal head number labels added.  At the top are the three voltage regulators 12V,  5V & 3.3V, these regulators are rated at 3.5A continuous 5A peak each. and are supplied by an old laptop power supply. The regulators voltage will be trimmed when under load conditions after wiring is completed.

Input Isolator Module used to provide the "one" input to "many" inputs to the various micro controllers.  The first example is a turn out being "reversed" is fed into a Standard Signal Control Module and a Junction Control Module, the second example would be a "Block Occupied" is fed into a Direction Sensing Module, Standard Signal Control Module, a Junction Control Module and a Three Light Signal Module.

40 input pins per module - due to a design fault I will be using 38.

4 x 10 pin headers - I dressed down the adjoining headers for a better fit after taking this photo.

Terminal strips labeled for "reverse" Turnout position inputs (Txx) and "Block Occupied" inputs.

"Block Occupied" inputs are 12V -Ve switched (black wires) the 2.2kΩ resistors are 1/2W as I did not have any 1/8W ones on hand.

The turnout "Reversed" are connected in series with the existing control panel LED's so two terminals per turnout are required.

I made a bo-bo with the number of direction sensing wire connectors - oh dear...  so I needed to fit 10 more in!  The concern is ensuring that the cable paths for the 6 core wires did not result in "tension" on the RJ6 connectors at the plug.

What I had..

The "remodeled" layout.

Connection inputs labeled.

I could not find RJ6 terminations so I discovered that you can but "sleeves" to fit inside of a RJ45 connector to use the 6 central wires.

Sleeves installed

There is much wiring still to be done...

The strategy is to "wire" all the physical connections between all the input signals to their respective direct or shared control boards.  If the input is to be shared "1 to many" then it has to go through an input isolator to avoid the "diodes in parallel" problem I have talked about previously.


I started capturing some video of what I have been doing but as I am so slow the playback is at 10 times the actual speed.

Part 1

Part 2

Part 3

Part 4

Part 5

I guess February will see a lot more "wiring"...

Other Activities

Rossco & I helped Wayne resolve two track issues: a reverse curve track alignment issue, and a section of "tight gauge" track on a curve.  Our Monday night round robin group moved a significant amount of "hobby goods" from the layout room into a spare room in Rossco's house so he can recommence laying track in the basement.

Overseas Trip

Rossco (aka Ros from Oz) and I will be visiting the West coast of the USA in late June starting in San Francisco, Sacramento, San Jose, LA,  San Diego, Denver then spending a day at the National Tran Show on Friday 8th July in Indianapolis before going to Columbus OH for the weekend followed by the East Coast covering Philadelphia, New Jersey and New York.  We hope to meet Lionel Strang in Toronto before travelling to York, Porthmadog & London in the UK.

If you will be going to the National Train show perhaps we could meet up for a meal on the Friday evening somewhere close to the show?  We will probably stay at the Holiday Inn Express Indianapolis Dtn-Conv Ctr Area.

Thanks to all those people who have either responded to my requests and those who through Model Rail Radio  have offered layout tours etc.  We are seeing just how much we can fit in and I will be in touch with most of you over the next month or so.

Till the end of February 2016.