GETTING CHUFFED


fitting lights and sound to an L&B train
(or how we got chuffed by DCC Supplies)


 

Without question, the addition of working lights to our larger locomotives and railcars have really added to the excitement of County Gate operations. It is also true to say that the additional complications of wiring up these locos can take up to an additional day's work.
 
On County Gate, loco whistles are operated from Railroad and Co. and the sound emanates from loudspeakers below the baseboards. At exhibitions, due to the ambient sound, this does seem to be a good solution as sufficient volume can be achieved to prevail over the general 'buzz'. One does have to admit, however, that the effect is less realistic for home operation.
 
 
The Lynton and Barnstaple Manning Wardles are the 'sausage dogs' of the narrow gauge world. I have always loved them but they are not to everybody's taste. When the railway was scheduled to be closed, Captain Howey, later of the Romney Hythe and Dymchurch fame, visited the line with the thought of saving it. He took one look at the 'ridiculous engines' and walked away!
 
There are enough issues just to fit the motor and flywheel into the engine along with a very small DCC chip (Digitrax DZ125). The cab is compromised but fortunately, the flywheel is largely hidden by the locomotive crew. The side tanks cannot be used for electronics as they have to be filled with lead in order to obtain sufficient adhesion for the locos to haul trains up our grades. If you are happy without a flywheel, it would be possible to fit the chip and loudspeaker in the cab. One can order this chip with mobile capability too although it is twice the price.
 
As one starts to fit lights to locomotives, the next issue that raises its head is how to take wires from the chassis to the body. Early locos fitted by myself used microconnectors (these can be purchased from Express Models and come up to six prong), but these do take up a lot of space and the loco cabs get full of 'knitting'.
 
I now build the microconnector plugs and sockets into the chassis and body. This is a far better solution and wiring can be minimised and place in the least unsightly locations.

connectors fitted to our latest Manning Wardle - click on image to enlarge

 
 
 
 

the anatomy of a sausage dog - click on image to enlarge
 
Locos are already united with 'companion cars' in order to enjoy more available wheels, for current collection. The obvious place to install sound is, of course, the companion car.
 
Our trains are designed to operate within schedules and as a consequence, only one side is ever visible. This has enabled us to open up the doors in the guards compartment to 'let out the sound' of the installed speaker. The open apertures were re-enforced by thin strips.

As the carriages are also going to be lit, all holes in the floors have been sealed off to prevent light leakage.
 

The two new brake cars with guards doors opened up for sound - click on image to enlarge

the first of the coaches nearing completion - click on image to enlarge
 
Equipment
 
So let us look at the general wiring requirement. One pair of wires between stock of this small scale is about all one can manage as the bending resistance of any more will derail the stock on curves. As it is, companion cars have to be quite heavily ballasted to prevent this happening.
 
The main chip, a Digitrax DZ125 remains in the loco. This will also operate the loco light, using function 0. The companion car also picks up track current and this is passed through to the loco using thin flexible wire supplied by DCC Supplies and micro connectors from Express Models.
 
To be able to switch on and off the carriage lights and rear lamp on the coaches, an additional chip is required. This is a Digitrax TL1 single function chip. This is very low cost luckily. Power for this is taken from the carriage track power pickups. The chip is set to the same address as the main chip and function 0 will be read, thus switching on and off the carriage lights and rear lamp when required.  As delivered, the TL1 needs a little programming. The loco address has to be set for the required train, and to switch the lights on and off with function 0, CV 61 has to be set to 1.
 
The TL1 needs to be removable for programming as the sound chip and the TL1 have some programming incompatibility. I used Express Models micro connectors to do this.
 
Fitting instructions for the TL1 can be found here
 

wiring schematic - click on image to enlarge
 
loco and carriage lamps
 
DCC Concepts in OZ produce tiny working loco lamps. In the UK, they are supplied by DCC Supplies but at over 31 for six, they are definitely not cheap. We have found the red lights seem to be effective but so far have problems with the white lights. These are not warm white, as one would expect from an oil lamp, but are that horrid blue white light which is, in my mind worse than no light at all. The manufacturer suggests that the problem could be solved by painting a tinted varnish over the optic.
 
The lamps are actually too small to Lynton and Barnstaple in 4mm/ft.
 
The wires of these lamps are very fine indeed and require careful handling. They are in fact so fine, that in many cases, they need not be hidden.
 
A separate circuit is used to power the rear carriage lamp in order to be able to correctly adjust the intensity of the light  A resistor up to 10Kohm may be required..
 
 
carriage lighting
 
The carriage lighting uses warm white sub-miniature lighthouse LEDs, again from DCC Supplies. These are soldered to a couple of brass wire bus bars which are glued onto the top of the coach cross partitions. Short lengths of heat shrink sleeves are used to insulate the brass bus bars from the metal partitions. It is important to use the correct resistors to ensure that the carriage light intensity is correct. I have found that 6 to 9Kohm resistors are ideal for us. If one coach has less LEDs than another, it is necessary to add an additional resistor so that the coach lighting intensity is equal. Our coach lighting is actually quite dim as indeed it would have been.
 

coach fitted with lighting - click on image to enlarge
 

only some of the coach lighting is installed at this point
 
Of course, when wiring the connection from one coach to the next, it is important that the polarity is correct for the LEDs to operate.
 
DCC Supplies
 
Once the donkey work had been completed, it was time to trolley off to DCC Supplies; fortunately very close by to us, just outside Worcester. The company resides in what must be one of the most pleasant business parks north of Watford. Nestling amid pine trees, meadows, a recreational lake and a small caravan park, husband and wife team Andy and Fiona have recently moved into a most spacious and well presented premises. The company is quickly enlarging its stock of model makers materials and is well worth a visit.
 

Andy and Fiona DCC!
 
Fiona tramples over all the usual  stereotypes of females and models railways... she actually knows a lot about them and is herself an expert on DCC operation. While Andy got to work fitting the function chip, Fiona programmed the sound chip.
 

working on 009 stock is like being a keyhole surgeon - click on image to enlarge
 

Fiona finally persuaded the sound chip to be a steam engine rather than a diesel!  - click on image to enlarge
 
It was not long before everything was neatly installed in the baggage car. I am amazed at how small the loud speaker actually is. It belts out a fair bit of volume too! Andy also installed a capacitor between the two lighting wires which stops flickering lights on bad bits of track.
 

the completed installation  - click on image to enlarge
 
There was even enough room to carry a few Albanian refugees too!
 
 
After very little hassle, the train was chuffing along the test track... see the video here.
 
There is still some programming to do. This includes assigning the required sounds to the specified function numbers. One will be a guards whistle which can be added to the chip. The chuffs also need to be adjusted so that there is the correct 4 fours per wheel revolution.  The sound of draincocks can be added for starting and the occasional safety valve blow off when stopped. Programming of the chip, and even the loading of your custom sounds is actually done through contact with the rails.
 
On returning home, the train was quickly railed onto County Gate where it happily chuffed around. Our neighbours arrived quite quickly to watch and the general consensus was that the effect is a rip roaring success. Hopefully, it will be possible to easily adjust the sound volume where required as this would greatly increase realism on a larger layout.
 
We started out with the wish to add sound for our new Bratton Fleming layout but now also hope to treat County Gate to the technology.
 
Following a second visit by Fiona of DCC Supplies both trains have now been programmed to work correctly. Our own choice of whistle sounds were loaded into the chip but for some reason, we were unable to add a guards whistle. We tried several sound samples but they just sounded like Casper the Ghost!
 
The number of chuffs per revolution was adjusted as indeed was the volume.
 
To programme this chip, a fancy circuit board is needed along with a good understanding of computers. There are three volume levels for the main sound, (the chuff). In addition, other sounds can be added to the chuff, such as braking, draincocks and pumps.
 
Additional sounds are actuated by function switches and these seem to have to be pushed twice to actuate the sound. There is no volume control for the function switch sounds so this has to be adjusted before loading into the chip. The sounds have to be in mono. Audacity is the perfect programme to do all of this.
 
It can take quite a few minutes to load the sound to the chip and then the result has to be tested. It took the best part of a day before we were happy with the results.
 
It appears to be difficult to assign function numbers to a particular sound and we have not quite managed to do this yet.
 
The result is convincing and excellent. It is important to maintain the sound levels correct for viewing distance and scale. Only too often, I see the sounds being played far too loud.
 
Our thanks again go to DCC Supplies and DCC Concepts.