Improving the Hornby-Jouef
Mistral 69 coaches (4)

Original page created on 19/03/2023.

Lighting

For this “Mistral 69” train set as for my PBA Trix, the power supply is provided, somewhat as in reality, by the generator van. In addition, to allow the mixing of these coaches, they are all equipped, except for the end coaches, with four-pole conductor couplers of my own making.

Electrification of the A⁴Dtux bogies

To power the whole train, it is necessary to have an excellent power supply, which leads me to choose the solution of the conductive bearings and the insulated half axles to equip the bogies of the A⁴Dtux coach.

The first step is to drill the bearings with the inclined drill (15°) fitted with a ⌀ 2 spherical mill bit. The descent axis remains vertical (arrow):

I dig out 1.5 mm, level off the inner surface and fit shoulder bearings. The axles (cut in two to be isolated in the middle) must be shortened a little to compensate for the extra thickness of the brass bearings.

Preparation of a bearing inserted in an epoxy card scrap:

Soldering the wire (uninsulated cable strand):

The wires are joined together on a self-adhesive copper tape. The ⌀ 0,5 insulated wires pass through a ⌀ 1,3 hole drilled in the pivot axis.

Click for a closer look at the connections.

Passing wires through the chassis

Passing the wires through a hole in the middle of the corridor would not be very discreet. Therefore, they are routed through the cabinets or lockers, except in the case of the van where this is not a problem.

As there is no space between the frame and the fittings, a passage must be milled in the frame (blue arrows) and a hole drilled in the fittings on both sides (red arrows).

Assembling the fittings on the frame.

Installation of the conductive couplings

See the article on these home-made couplings.

Move the mouse over the picture to see the details.

In this picture, there are a few details to note:

• The three wires are grouped together and enter the chassis through the same hole, in which some Krystal Klear glue has been deposited. These wires are:
  • the positive pole of the power supply, blue;
  • the light control, green;
  • the lamp control of the end coach opposite the generator van, yellow.
• To prevent the wires from catching on the return spring clip, a small bridge made of Evergreen, 0.5 mm thick, is provided.
• On the NEM box side, the male PCB coupling has its tail blocked by a 1 mm Evergreen shim, and the wires are held in place by a tie which prevents fatigue breakage at the solder joints.

Installation of lamps

Because of the small number of copies to be made, I did not plan a professional circuit. I made them with a 60° milling bit.

These are 4 × 8 mm plates glued in the inner corners of the chassis ends.

Wiring of the lamps according to the previous drawing. The LED are SMD 0603.

Click for a closer look at the circuit.

The wires (independent for each LED) pass through ⌀ 1.6 holes drilled in the ceiling on both sides of the body end, so that they remain invisible from the gangway. The LEDs will be connected in series to the lighting strip.

Testing the lamps to validate the dimensions of the CI plates. In this front view, it looks like the LEDs are squinting, but it is much less apparent in reality.

Decoder

The decoder is a Lenz LF101XF. It is obviously installed in the generator coach.

The anti-flashing capacitors are installed with their charging circuit on a padded circuit board.

One can distinguish the padded circuit which includes two 2200 µF capacitors, a 100 Ω resistor and a 1N4001 diode.

Lighting strip

Front and back view of the lighting strip manufactured by JLCPCB.

Click for a closer look at the strip.

The visible side has been covered with white self-adhesive paper. The manufacturer offers a white varnish directly, but for the chosen IC thickness of 0.8 mm, there is a significant extra charge. I have since found that this extra charge does not apply for a thickness of 1 mm, which is quite acceptable.

The assembly here is for the A⁴Dtux generator van coach, where the wiring is the most complicated. The strip is stuck with thick double-sided tape.

At the front, the wires connected are: the power pickups (red and black); the positive common (blue); the tail coach’s lamp control (other end - yellow); and the light control (green). These last three are transmitted to the next coach by the three-pole conductive coupler.

At the rear are the same, plus the white wire for controlling the lamps, which are wired to the end of the strip.

After testing the reassembled coach, I noticed that the roof and walls of the van part are translucent! So I slipped some black paper on both sides, and glued a reflector in survival cover under the roof, unfortunately not wide enough. The correct width to cover the whole roof would be 36 mm.

Final result

View from the compartment side, medium-dark atmosphere.

View from the van side, dark atmosphere, lamps on.

View of the compartment side, almost dark.

For the moment, there is no transparency of the body. But let’s look at the same photo, with the brightness increased. We can see that there are indeed light leaks, especially at the bottom of the roof and under the windows. However, they are hardly visible under normal conditions, even in low ambient light.