July 2016

Please note that future “Show and Tell” evenings will start at 7.45 prompt. This allows full time for all to have a fair share of the time available.

OO Gauge Matters

Track laying

Fiddle Yard Trackwork

Time has been spent on reinforcing (re-soldering) track to sleeper joints at various yard locations.

Track laying

The “short length of track” mentioned in the last CC has been completed and now runs into a section that enables locos to be “turned”.

General Baseboard Wiring

To improve reliability work is underway to replace the “SCART” connectors with 25 way D shell  connectors. The opportunity is being taken to also replace and or “tidy up” some of the wiring.

Redbridge Control System

The following is a summary of the complex system that Dave has designed. A detailed explanation is available via Dave’s recent emails and he has produced a schematic diagram below.

The layout is basically split into 4 areas: the fiddle yard, the up line scenic area, the down line scenic area and the wharf yard.

The main points are:

1. There will be two control panels. The Black Panel at the front controlling Redbridge Wharf and the other at the back controlling the Fiddle Yard. An umbilical cable will run between the two boxes and terminate in socket A in the Front Control Panel.
2. There must be provision for both DC and DCC control
3. One key issue is that the two types of contol: (DC) and (DCC) must never “meet up” (the result would be a damaged control system).
4. To ensure that it is NOT possible for the two types of control to meet it is necessary that only DC or DCC can be applied to the WHOLE layout.
5.  There will be a Switch in each of the two control panels (DC and DCC). For it to be possible to use one or the other form of control it is essential to incorporate a “master” switch (or rather two 9-pin D shell sockets with a single plug in each). The plug is connected to the track feed sockets and can only be in one socket at a time.
6. An umbilical cable will deliver 0, 5v, 12v and the Arduino control bus (I²S) from the wharf control tower to the fiddle yard control box. In the opposite direction flow the DC track feeds for the up, down and yard areas plus the DCC track bus and the NCE two wire control bus. There are also a couple of other control wires to allow coordination between the front and back.
   When running in DCC mode it is necessary to split the layout into different power districts so that a short circuit, due to a derailment or the like, does not cause a shutdown of the whole layout. Each of the 4 districts has a DCC supply fed through an overload protection device. One in teh fiddle yard control box that will feed the whole fiddle yard, and three in the main control tower feeding the other sections. These are MERG kits. They are marked OPU (Overload Protection Unit) on the diagram.
7. There is an umbilical cable that delivers 0, 5v, 12v and the Arduino control bus from the wharf control tower to the fiddle yard control box. In the opposite direction flow the DC track feeds for the up, down and yard areas plus the DCC track bus and the NCE two wire control bus. There are also a couple of other control wires to allow coordination between the front and back.  A peculiarity is that the Redbridge Wharf DC control feed is taken from the front control tower to the fiddle yard control box and back again. This is to allow the switching between DC and DCC to be in one place. 
8. There are several other boxes on the diagram marked UTP.  These are the points where DCC controllers can be plugged in and consist of a couple of RJ-12 (telephone cable style) sockets.  Any NCE handheld controller can be plugged into these and allow control of locos etc.  These are all connected to the DCC system via a two wire control bus (a pair of red and green wires on the diagram). 

EM gauge Matters 

The AGM will be on Wednesday 12^th October at the club room starting at 7.45pm.