Lima 42 Remotor + DCC

The old Lima 42 class diesel has been around my layouts for decades and I am not too proud to run it mixed in with all my more recent and highly detailed models. It ran well on DC and even better on DCC with a LokSound V4.0 decoder coupled with a replacement pancake motor and pickup on all wheels.

The motor shown in the top 2 photos was purchased on eBay as a specific replacement for the 42 class and other similar models. It satisfies the requirement of isolating the motor from the frame for DCC and runs well.

I always try to achieve pickup on all wheels or as many as possible. In this case it was easy. I added two small pieces of PCB to form solder pads. They are clearly visible attached to the two sideframe brackets with epoxy and carrying the RED flexible feed wire and the phosphor bronze pickup wires.

Note the holes shown in the bottom of the chassis to the top left. These are for the speaker shown in later photos.

A thicker piece of copper wire connects the 2 pads and one carries the p/bronze wires for 2 wheels and the other for 1. The photos show the setup.

The photos above and below show the decoder attached to the roof of the body shell with Blu Tack and small piece of strip board (Veroboad) used to carry the series resistors (1k – 1000Ω) for the front and for the rear headlights. Notice the “interrupts” cut into the tracks under the resistor. These were made with the tip of  a small drill. This isolates both ends of the strip. Normally the resistors would be mounted on the other side of the board but this method works  just as well

In the photo above I have removed most of the interior glazing except the sections for the front and rear windows. The portholes are glazed with Butyrate 15 thou strips held in place with tiny spots of Canopy Glue. [K & S Clear Plastic Sheet #1308]

In this model I used a 5mm (front) and 3mm (rear) yellow glow LEDs with ends of the LED filed flat and then polished. To avoid light appearing from other than the headlights, I carefully painted all but the front of the LED flat black.

I couldn’t find an appropriate and cheap socket to accept the 8pin decoder plug on the LokSound V4 so I made my own from a machined pin DIL (Dual In Line) IC (Integrated Circuit) 8 pin socket (eg Jaycar part# PI-6452 or on eBay).

The first step is to carefully cut the socket into 2 parts…

… as shown here.

Clean up the cut edges – the ones below need to be filed, but it’s not important as the correct spacing is achieved by gluing the IC socket back together on the smooth faces…

… as shown below with the prepared pair stuck in a blob of Blu Tack. Rough the surfaces a little and bond together with a spot of epoxy.

For this installation it suited me to bond the lead weight into the chassis with silastic and epoxy the prepared socket to the top of that. I have an old plug cut from another hard wired LokSound decoder that I can use as a guide to indicate which coloured wires need to be soldered to the rear of the new socket.
Note that installing the socket this way means that the off-centre plug can only go in one way around (good).

The mounting position of the speaker is shown above requiring some holes to be drilled in the bottom of the chassis. The speaker (which is not my preferred sugar cube type but was one of a number of spares I had in the workshop) is mounted just clear of the surface to allow sound to escape into the body shell. The speaker fits within the its housing but importantly, needs to be very carefully sealed into the housing. I use Canopy Glue on a toothpick to carefully seal every gap around the edge of the speaker, keeping it clear of the speaker cone. Also seal the spaces where the wires exit the housing – silastic may be better here.

This was the 25mm (1″) 4Ω  1.5Watt speaker and enclosure used for this project.

Here is a short video:

“Charles” Gets a Decoder

A project with a difference – PART 2.
A friend has a Fleischmann™ type 4028 0-6-0 Steam Locomotive which he would like to use as a “proving” loco for his under-construction Wolgan Valley layout. It’s a sort of a recycling exercise. This is the next exciting episode – Charles gets a decoder!

The decoder is a LokSound V4.0 running the ESU sound file: 54413-LSV4.0-Dampf-BR80-R5      It sounds like this:

Very Germanic!! But it will be OK for the purpose, assuming that the NSWGR may not have bothered changing the whistle.

This is where the LokSound decoder will reside. For a tank engine, the Fleischmann 0-6-0 has plenty of room. After a little testing, it was least obtrusive in the cab roof and is held in place with Blu Tack.

There are other things to do with DCC sound installs one of which is the Speaker and more details will follow. This is one is my favourite Sugar Cube speakers in my favourite mounting area – the smokebox. That way the sound comes from the right part of the loco! [post coming on fitting a sugar cube into the smokebox of a brass 30T class loco]

The motor, especially in this ringfield type requires special attention to make sure that it is isolated from the frame.
There is excellent technical advice on this in an article I obtained on the “All Aboard” Mittagong website – except it doesn’t seem to be there any more. The original PDF file I downloaded from “All Aboard” is however available HERE.

The replacement Isolated Motor Shield is shown below fitted to the mechanism. It is sold as Fleischmann replacement part # 50 4730 and is available from All Aboard as a spare part (not shown on the web site).

Here you can see the wiring from the decoder to the motor – Orange and Grey to the motor and Red and Black to the track pickups (loco frame and wheels). Some other wiring is visible and is described below.

The decoder has a number of unused function wires and they are held captive by the (yellow) kapton tape. Two extra simple PCBs are also visible. Simple PCBs are described in THIS POST.
The one on the LEFT has 4 strips – 2 carry the brown wires to the speaker (in the smokebox) and 2 carry the wires to the front headlight.  The bottom strip can be seen to have a connection via a resistor to the WHITE function wire (headlight).

The value of the resistor is 3k3 (3,300Ω) indicated more clearly on the board to the RIGHT where the colour code is ORANGE, ORANGE, BLACK, BROWN, BROWN which is 3 3 0 (1 nought) and (1 percent tolerance) ie 3300 Ohms ± 1%  This value is higher than most people use but it provides a more prototypical yellow glow in the Warm White LED.

Image© courtesy eBay

Incidentally the LED is a tiny pre-wired device where the LED size is 1mm x 0.5mm and is available in Warm White, Bright White, Red and Green & available on eBay for ridiculous prices.

Sold as: Pre-soldered micro Litz wired leads Warm White SMD LED 0402

They will fit into the smallest headlights on a loco but must be handled with care.

The pcb to the RIGHT is shown in detail below and feeds the rear headlight and the 3k3 resistor is on one strip which has been interrupted under the resistor making 2 isolated pads.

The common wire is BLUE and feeds to both small PCBs. The YELLOW wire is the function output to the rear headlight.

The speaker used is a Sugar Cube which measures 12mm x 14mm x 5.4mm thick (bare). This is one being prepared in an enclosure.The following speaker is ready to go in:More about speakers in a separate Post.
And to save you scrolling back up – the photo below is repeated and shows the sugar cube sitting in the Smokebox and under the chimney which has been drilled out so that the sound is coming from the front of the loco both top and bottom. I will go to any length to try to get the speaker OUT of the tender and into a more realistic place. You can detect the difference in a passing HO loco.

If the speaker enclosure is mounted on the chassis it is inconvenient to wire as a plug and socket arrangement would be needed. Instead, I have located the enclosure to the inside of the body shell by the simple of expedient of a blob of Blu Tack in the top of the body which “grabs” the speaker when you assemble the two parts.  [Yes, I know … there should be a plug connecting the decoder and the motor/pickups but I got lazy]

Here is another loco with homemade plugs and sockets so that the body mounted  speaker can be separated from the chassis:The 2 brown speaker wires from the decoder are connected to the speaker via a 2 pin plug. The body and chassis can then be separated. This loco is a 73 class shunter.

The next episode will cover painting into NSWGR “colours” but in the meantime, here is a preview of “Charles” making some noise! Deutschland Über alles!


The basics of DCC at “Brolgan Road”.

The backbone is a commonly used NCE system comprising a 5 Amp power supply to the left and the Power Pro DCC Command Station to the right.
The primary controllers are both wireless and consist of a Procab on the left and Cab-06 on the right.

The wireless antenna is mounted high on the wall and coverage is excellent in the small layout room.

Ground zero is near the main station Brolgan Road. A laptop slides out from beneath the layout when required. Left to right on the fascia: Brolgan Road Panel; the only NCE cab bus outlet (no others required with radio); a switch to isolate Brolgan Road DCC sub bus and the Procab. The shelf underneath houses L to R: a 12V power supply for the Canbus/ servos/ ancillaries; a grey box controlling power to the layout via DCC or DC (rarely used – just for testing); two track sections used as “Programming Tracks” – one for JMRI and the other for the Lok-programmer (shown below).

JMRI DecoderPro provides another throttle but more importantly, a means of programming the decoders in locos in a simple way and while operating on the main (line).

JMRI  stands for “Java Model Railroad Interface” – it is an open source program for model railway (railroad) hobbyists. It includes DecoderPro, Panel Pro and a Throttle. The computer above runs on the house WiFi and in my case I have a WiFi extender in the layout room as the signal from the router (modem) in the house is patchy.

Other throttles which can be used include:

  • smart phones,
  • tablets
  • iDevices

… using either “Engine Driver” app on Android or WiThrottle on Mac. Phones need to connect to the WiFi network in the layout room.

The DCC signal is fed to the rails and provides power to the loco; control of the loco(s) and other devices; and sound – if the decoder is so equipped. On the photo above the DCC main bus is “A”. There are some excellent websites explaining DCC operation and wiring and one of the best is by Marcus Amman at Main North.

The other Bus pairs shown above are:
B – 12 volts to power servos and other equipment.
C – DCC sub-Bus (because even though you can run ALL of your layout on the main DCC bus, it is bad practice when it comes to fault finding short circuits or other problems. Much better to isolate areas so that the fault can be found and operations can continue on the rest of the layout.
D – my CANBUS which is a control system which manages everything on my layout. See the post on MERG.

On the drawing board is a lot more material on DCC for future posts… Rick


MERG (Model Electronic Railway Group) is an international, UK based group promoting interest in the application of electronics & computers to all aspects of railway modelling (quoted from their Website).

That covers one of my railway modelling interests and the annual fee of £20.00 (+£5 joining fee) is reasonable and includes a quarterly journal and access to a vast amount of information including a forum where your questions can be answered.

If you are doubtful about the quality of the group, you can download from the website a FREE book written by MERG member Davy Dick, entitled “Electronics for Model Railways”. This is a very comprehensive and informative introduction to the subject and I would highly recommend it as a worthwhile read.

MERG offer a growing list of kits, including Train-on-Track indicators, Gas Lamp Twinklers, a Computer Control system, DCC and the new CBus Layout Control System are available to members and, on occasion, ‘bargain’ components of model railway relevance. There are also basic projects & kits called Pocket Money Projects and these would appeal to starters in the hobby and those less confident in “things electronic”.

CBUS:  This is a universal layout control system developed by MERG members. The designers describe it as “a system for comprehensive layout control based on a general purpose Layout Control Bus (LCB). 
So what are the functions of a layout control system. You can divide these into two basic categories:

  1. Control of devices (outputs)
  2. Detection of ‘states’ (inputs)

Examples of (1) are changing turnouts (points), signals, power to block sections, turntables, level crossing gates, layout lighting, setting routes, controlling the speed and direction of locomotives (by DCC or analogue DC) and any other electrical or electro-mechanical devices that may be on a layout.

Examples of (2) are control panel switches, block occupancy detectors, bar code or RFID readers, turnout direction sensors, turntable position and ‘RailCom’™ track detectors.”

The choice of CAN: The CAN bus (Controller Area Network) was developed by the Robert Bosch company in the 1980s for use in motor vehicles but has since been applied to many other types of machinery including aircraft and medical scanners to name just two”.
Davy Dick, in “Electronics for Model Railways” describes it like this: “Imagine building a new layout consisting of four boards. With CBUS all you need do is run
four wires the length of the layout – two for power and two for the control system. No matter how many switches, button, lights, points, track occupancy detectors, accessories, etc. you now add to the layout, you still only need those four wires. The accessoryconnections between boards are always just these four wires – not the scores of wires associated with conventional wiring.”

But what does it look like on my layout, Brolgan Road?

In order to find out I built a small test panel to check things out as shown below. In simple terms the process runs from RIGHT to LEFT

  • starting with the module called CANUSB4. It connects to a computer off to the right by means of a USB cable and to the CANBUS twisted pair (red/white)
  • then comes the board labelled CANACE3 (to the designers, these acronyms made sense, but they puzzled me!) which is a switch interface that can handle 128 toggle
    switches or 64 pairs of push buttons. The module talks to the CANBUS and tells other things, in this case specific Servos to do something eg. operate points.
  • the module at the left labelled CANSERVO8 (I can understand this one – it controls 8 servos!) listens on the CANBUS and when it gets a message relevant to the points it controls – it talks to the particular servo concerned, and alters its state (normal or reverse). The servos do the business.

It’s interesting to note that the previously mentioned 4 wires seems true here (2 for CANBUS and 2 for 12DC to power modules, servos, lighting etc). But what about the DCC bus? That’s another 2 and it’s very prudent to divide the layout into SUB buses for DCC.
For example, Brolgan Road has 4 sub buses – loco, yard, carriage works, main station area and a number of isolating areas controlled by microswitches to isolate the areas either side of the lifting entry flap. Then, of course the servos have to be connected to the CANSERVO by cables and so it goes on!
BUT – if you are methodical and use colour coding and write a master list, then wire neatly and use labels, all will be well.

The video above shows a test rig built on a board being used to move a servo, in this case to find its centre position. The test rig consists of two Pocket Money Projects (PMP). The one on the left is a “Servo Controller/Tester” and all it does is respond to the position of the control knob (operating a variable resistor). It allows me to make sure the servo arm is fitted in the correct position – giving equal movement each way.

The PMP on the right as called “Ezy Points” and you will see it working in the video below. It is connected to a turnout test bed so that I can test the movement of the point blades. The 3 BLUE objects on the circuit board are variable resistors (aka potentiometers aka “pots”) which adjust 3 things manually with a screwdriver: speed; movement Left; movement Right, so that you can make the poin blades “kiss” the stock rail.

These PMP projects are fully described in the free book “Electronics for Model Railways”

An earlier test rig (below) better shows the “pots” (blue) and the standard RC (radio control) cable – yellow, orange, brown. You can get these in various lengths from hobby shops dealing in RC aircraft. Or, you can buy them on eBay very cheaply. You can plug them together for longer runs.
If you had a tiny shelf layout with a couple of points, you could use a few “Ezy Points” to control them. OR – you could use the servo to activate any other moving thingy eg. a gate, a signal etc. anywhere on your layout. Of course then you haven’t got remote control of all aspects like you have with CANBUS (or DCC).

The servo cable would normally come out the bottom of the layout.
Here is a close-up of the CANACE3 printed circuit board (PCB). You can buy the complete kit from MERG or just the PCB as I do and source the parts locally.
The soldering is not difficult but it requires practice. I will try to develop a VIDEO showing the process.
This is a close-up of the CANSERVO8 and this is a beautifully designed PCB of a more modern style. This board can control 8 servos and 2 are plugged in at the top. The long device in the centre with lots of legs is an IC and it can be purchased pre-programmed. It has all the “smart stuff” that responds to signals on the CANBUS and then bosses the servos around!

Controlling Mains Power on a Layout

This is a simple topic and one which may be of no value if you have a tiny layout.

In my case, with a layout running around the walls, I had 3 mains power outlets all of which would be difficult to access when the layout construction was under way and completed.

This Remote Controller is one of a number that are available which allow you to switch varying number of outlets. This one does the job for me.
Check on-line for pricing (look up: remote control power outlet)

The switched outlet plugs into the wall socket as above. I can turn ON ALL with one switch or select which one I want.
It is also useful for me to divide the layout power into three sections which eases the load when powering up. Others have more than 3 controlled outlets.

Making Simple PCBs

Printed Circuit Boards (PCBs) are possibly a step too far for many railway enthusiasts. However the material lends itself to many simple possibilities.
What is PCB? There are two main types:

  • a board based on glass reinforced resin and coated with a thin layer of copper which is a good conductor and easily soldered. Some PCBs are double sided, ie. coated with copper on both sides. For our purposes, both could be used but there is not much advantage in double sided boards for these simple projects.
  • an earlier type which is based on a phenolic material, dark brown in colour and somewhat brittle. Otherwise similar to the above

The PCB we want to use is BLANK PCB which can obtained from on-line
or retailers like Jaycar® or Altronics® in Australia.

The 3 PCBs above are all based on glass fibre PCBs. The one in the middle is the focus of this article. It is a Power Supply.
The other 2 boards are produced by the MERG (Model Electronic Railway Group in the UK). Members can buy these boards either as a kit (with all parts) or just the PCB for the owner to purchase the parts and assemble. The latter is what I have done in these 2 boards.
In these complex PCBs, a series of “components” are connected by conductive “tracks”. The components are soldered to the PCB through holes in the board.
In simple terms, the one on the left operates up to 8 servos which can be controlled by the one on the right. The latter handles input from switches.

The rest of this post will focus on how to make simple PCBs even more basic than the one outlined above.

Rather than a Terminal Strip with screws:
The PCB on the right is about as simple as you can get (& cheap!)
It is divided into 2 discrete parts by making a saw cut through the copper cladding. Each half is a separate part of the circuit. One for the RIGHT rail of the DCC supply and the other for the LEFT rail.
A couple of screws hold it to wood in this case. It could have been glued (epoxy) to the wood or to the underside of a foam layout with contact cement. 2 screw holes are needed.
The copper is cleaned with fine wet & dry or a fibreglass brush. For ease of soldering under the layout, I made 10 small starter “blobs” of solder.

The pic above also appeared in the Track Feeder Post
Whilst this one looks slightly chaotic, it shows a couple of other aspects:

  • the PCB has been glued to the base of the foam with contact cement.
  • the piece of PCB is super simple – the copper has been split into 2 sections by using a modellers razor saw (see below)
  • colour coding is obvious and important
  • the 2 CBUS wires (red & white) to the far right have been held in place using a low temperature glue gun.
  • the purpose of the exercise was to feed DCC power to 4 adjacent tracks on the turntable.
    To do a simple divide on the surface of copper clad PCB you can use a home made (left) or purchased mitre box (right).
    Just make sure that both segments are electrically isolated using a test lead or a multimeter on the Ohms range.
    To make the PCB on the right, cutting with a saw, as described above, will not work.
    A cutter such as a dental burr or a “Dremel” engraving cutter such as this one is needed in a rotary tool or drill press.
    This one is a #111 engraving cutter but I think #105 or one of the
    others as shown on the Dremel Site should work.

     This is the finished product PCB.
    It converts 12V DC to 5V DC which is required in some circuits.
    The construction technique is UNUSUAL but SIMPLE to use for basic circuits. In effect a bit like modern boards which are made using SMDs (Surface Mount Devices) except that the latter are TINY, almost microscopic.

    This is the circuit diagram for the project described above including the “pinouts” of the 3 leg 7805 voltage regulator IC. Feed it with 7-35V DC and it will deliver 5V DC. The function of this board was to provide 5V to power the servos controlling my points.
How to Cut the Grooves:

The “pads” of copper will form discrete parts, or “pads”, of the circuit for this 12V to 5V converter.
Below I am using a small bench drill (or a rotary cutter like a Dremel) with a guide clamped to the left. To set the depth of the cutter, the simplest way is to adjust the cutter so that it just touches the surface of the copper, then slide the PCB away and place a piece of paper under the board which will raise it enough to route a groove. You will need to experiment with the thickness of paper but a thin piece is all that is required.

A slightly more crude approach, but one that will work, is to mark out the pattern with a pen and freehand cut the grooves. The electricity won’t mind if the edges are a bit ragged! But check that each area is not shorting to a neighbour with a meter or test lamp.
Treat the cutting tool carefully with respect to SAFETY . Wear safety glasses. If cleaning up with a fibreglass tool, vacuum up any loose material – it has an attraction to entering your skin!

The NEXT STEP of installing the components involves SOLDERING so see the Soldering Post to reproduce something like the little power supply above.

At present I will continue this post to show how to use super simple pieces of PCB as an aid to wiring layouts and panels.

The example above is the rear face of a control panel (see the Post on Control Panels). Several pieces of PCB have been attached to the back of the acrylic panel material. The long strips distribute a connection to the DCC bus. This is used to operate the LEDS, shown later, which reflect the setting of the points switches and the solenoid position. The smaller squares terminate the connections from the LEDs via 1k resistors.
The PCB here brings in the connections from the module that controls the point switches shown in the first photo. The connecting cable is called “rainbow cable” and sells from suppliers like Jaycar in 16 wire ribbons. Other suppliers have even wider cables but they all repeat in batches of 10. This cable makes figuring out which wires go where, much easier.
Strain relief on the cable is provided by clamping an additional piece of 2mm plywood. The mounting ply and the PCB are epoxied to the recycled picture frame housing the panel.
The panel shown above is now complete and ready for testing. At the back, the LH PCB connects switches to the panel. This board was made using techniques shown above.
The right hand board is a piece of commercial strip-board sometimes known as Veroboard. This board is bringing in connections to the frog from 8 points. This signal is used to set indicator LEDs showing which track is “set”.

This gives some idea of what the panel does – the LEDs indicate which road is set. The switches also indicate the road but the LED is easier to see and actually indicates that the road has power. The switch on the right is replicated on the next panel and can be controlled from either panel.

Control Panels

This is the method I use for control panels on my HO Australian (NSW) railway layout.
Like most things on my layout, I try to find an easy way to do things by using materials readily obtained. The panels shown below are paving the way.

This is an operating panel for “loco” on my layout. The SPDT switches control the points (US – switches, turnouts) and indicate which track is powered by a 3mm Green LED. The next panel to the right operates the turntable (below).

These panels are constructed using 3mm black acrylic plastic sheet (purchased as a pack of A4 size sheets on eBay). The panels are held in photo frames. These were a cheap 16 x 11 cm frame from a “discount” shop and were supposedly a standard item – not so … subsequent ones were different design, size and colour! The next photos show how the panels were mounted to the fascia using 2 simple wooden, angled holders.
Size “A” above is the same size as the internal height of the picture frame and needs to be a tight fit. The 2 wooden holders need to be spaced such that they are a tight fit to the internal width of the frame.
This is a panel under construction for the “yard”. This time the picture frame was an MDF cheapy. I prefer the moulded plastic ones. It looks OK when assembled (below).

And shown above mounted to the layout fascia. Switches and LEDs still to be added. The point lever to the right controls crossover points on the mainlines to the rear using wire in tube (in this case bicycle gear tubing). The manual point operation is more prototypical for 1950s operation but I will probably convert them (and did so) to servo operation.
Firstly I produce a really rough pencil sketch to replicate the physical track layout, in this case, in the yard. The point numbers need to be allocated and recorded as I am using MERG designs developed in the UK.
Their aim is “to actively promote and advance the use of electronic and computer technology for model railway operation”. In essence I am using their CANBUS model with a variety of modules connected to that BUS, a sort of fly-by-wire. For a detailed explanation – see the MERG website.
The reverse side of the acrylic sheet is shown above (right). It is plain brown self adhesive paper and makes a suitable surface to draw a pencil diagram following the design sketch but drawn accurately using basic drafting techniques (mostly a 45° set square!). Using a soft pencil you can easily make corrections to the diagram. I use a line width of 4mm.

PHOTO description of the process now follows.

Having marked it out and checked it, I carefully cut along the lines, missing the gaps with a very sharp (new) Exacto blade. Just deep enough to cut through the paper. Check that the cuts meet precisely! No gaps. When everything is cut, peel the 4mm strips slowly from the acrylic sheet.
You are left with most of the paper still there and some black 4mm strips where the tracks go. The next step is to spray paint the whole panel with a rattle can. I used a satin white enamel with about 3 light misting coats. When touch dry, peel off the remaining paper to leave your track diagram.

You are left with most of the paper still there and some black 4mm strips where the tracks go. The next step is to spray paint the whole panel with a rattle can. I used a satin white enamel with about 3 light misting coats. When touch dry, peel off the remaining paper to leave your track diagram.
One little patch-up was needed on the example below – the knife slipped and I covered the mistake with a sliver of blue painters tape.
I use a satin white rattle can in my home made spray booth (based on a kitchen exhaust fan). Separate POST done but not added yet.
Multiple light spray passes with satin white – leave to dry for 20 minutes and multiples passes again.
Careful peeling of the self adhesive backing.

This is the final version of the Loco control panel expanded to include the 2 crossovers on the adjacent main line. Things always change on a model railway layout.

An Overview of the Operator Panels

There are 4 main Panels:

  1. Brolgan Road – station area
  2. Loco and turntable (sub panel)
  3. Yard
  4. Carriage works

And one intermediate panel between the yard and the carriage works. Using the MERG Canbus system allows panels to overlap so that panels can include points in the adjacent area (with permission from that operator).