Tag: Hornby models

Add keep Alive to Hornby Jinty

I bought the Hornby Freight set. It came with a class 8 shunt diesel and a Jinty steam loco. At the time of the purchase I added a keep alive capacitor to the diesel shutter and housed it in the radiator. The Jinty had an open cab. There was no room for the capacitor any where so I couldn’t install one. While browsing the internet sight of YouChoos an option presented itself. It was a 6800uf super capacitor. My reasoning suggest that it might be able to be installed in the bunker. One was bought on spec. It turned out to be just the right size to fit the bunker of the Jinty.

Note the position of the capacitor in the bunker. Look closely. The capacitor is clear of the mounting hole.

To start the body of the loco was removed. The DCC chip does not have the usual heat shrink plastic cover on it. It was removed from the clip in preparation for soldering. A very small hair sized insulated blue copper wire was soldered to the + of the capacitor. A similar piece of white wire was soldered to the – of the capacitor. These wires were about 4 inches long. The capacitor was fastened into the bunker via double sided tape. Be careful to not cover up the little cutout in the body for, if it is covered you won’t be able to get the body back on the chassis.

Next task is to run the wires to the DCC chip. I fastened the wires to the body via the use of a little Loctite 401. Super glue will also suffice. In either case don’t glue yourself to the model. In the photo you can see how I routed the wires in the tanks on either side of the loco. It went under the footplate on either side too. The visible part of the wires were painted black. The glue was applied using a small Jules’s screw driver. This helps. A small pair of tweezers will be of assistance as well.

You can see the capacitor in the bunker and where to solder the wires on the chip.

A third hand is recommended. Something to hold the DCC chip steady. The photo shows how the two wires were soldered to the points on the board. Remember that blue is + and white is –. Care should be taken when soldering. You don’t want to bridge any connections. Use a visual aid and a small soldering iron. This stuff is so tinny that it is like grains of sand. Loose one on the floor and you will never find it. What I am saying is this. If you are not familiar with such fine soldering work, you might want to get someone to do it for you. Or alternatively go on line and learn about how to successfully do this kind of work. Once this is done the DCC chip can be put back in its clip and the body can be fitted back on the loco. Now comes the time to test. If all went well, the loco should have a functioning keep alive feature.

A close up of the jinty’s DCC chip so you can better see where the wires go.

My loco used to stop on points from time to time. Having keep alive functionality helps the loco get over these spots without faltering. How it works. The super capacitor is like a small battery. It supplies power to the chip for a few seconds. This allows the loco to still operate for a short time while it passes the dead section. Enjoy your modeling.

HST 125 unit ditch and tail lights

 

DSCF1210

You back already. The device in the picture is what is needed for the power units. Basically it consists of a piece of a LED lighting strip cut from the extra ones I bought. After trial and tribulation I found out that these things appear to be connected in sets of three LEDs in series with a resistor. You will notice that there is a scissor mark in the middle of the unit. I choose this section because I know that the two LEDs are not connected to each other. Therefore they can be treated as discrete units. Take a closer look at the unit. Clicking on the picture will give you a close up view. Notice the positive rail marked (+) is closest. The 1000 Ohm resistor has one lead connected to both white LEDs at the anodes. It is then trimmed off. The lead on the top is bent over and cut short. I used the remainder of this pig-tail to connect the two cathodes together. This forms the basics of the circuit. The tail lights are connected directly to the wire joining the two anodes of the white LEDs. Another piece of tinned copper wire was obtained from the rubbish before it got to the bin. It was also a cut off pig-tail. This was soldered between the two cathodes of the red LEDs.

Fig. 1
Fig. 1

How did it all get there? Read on. First I tinned one leg of the 1k resistor. Soldered it between the two white LEDs at the anodes. Then I bent the resistor leads into the shape you see and trimmed off the excess from both the furthest LED and the opposite end of the resistor. The longest pig-tail removed was long enough to use as the connection between the two cathodes of the white LEDs. Note the small extension past one end. It is to facilitate connection of the white wire. Next using super glue applied to the base of one the gull-wing LEDs stick it in place on the surface of the unit up against the anode wire with its black line closest to you. Do the same with the other gull-wing LED.

Using a flux pen wipe flux over the two places where the gull-wing LEDs touch the wire. Then solder these. Be careful while doing this. These devices won’t take much heat. Place another piece of pig-tail under the other two gull-wings. It should fit pretty slug. Using the flux pen apply flux to these joints and solder them in the same fashion. Note the length of this pig-tail. It should have a bit of an extension for the yellow wire. Once this is done solder the coloured wires on as per photograph.

Now we need to test the device before sticking it to the power unit. With a 15 volt power supply connect the blue wire to the (+) positive of the power supply. If everything is all right the white wire touched to the (-) negative terminal should light the white lights. Doing the same with the yellow wire should light the red lights. To the loco or power unit as they are called.

Remove the body of the unit. At the front remove the bulb and its wiring. This article assumes that you have already converted the unit to DCC. Behind the bulb there is a black plastic panel. The unit should be trimmed to fit this. Make sure that there is no oil, dust or dirt on the plastic panel. Test fit the device we created on to the panel. Once you are satisfied with the fit take the cover strip from the back of the device and stick it in place. The white LEDs should be at the top and the red ones at the bottom of the power unit. The wires will be to your left as you look at the front of the unit. You shouldn’t have any trouble working out where to connect the wires. After all they are colour coded the same as the DCC chip’s wires.

Place the power unit on a short piece of track. Connect up your DCC controller to the track. Select your power unit. Switch on the head light. If you are in forward gear the white lights should light up. Change to reverse. The lights will change to red. Put the body back on the unit. You are done. Note you may have to advance the throttle a little to get the chip to change direction. There is one more unit to do. I choose to use a second chip in the rear unit to operate the lights on the rear. It does seem to be a bit of a waste though. There is a little trick to remember when wiring the rear unit. Connect the white wire to the yellow one and vice versa otherwise you will have white at both ends in forward and both ends red in reverse. The Hornby “Select” controler doesn’t like two chips with the same address on the layout. It will complain.

Tools used on two projects shown in photo bellow. There are three items missing from the photo. They are a white out pen, a pair of scissors and a roll of electrical insulation tape.

 

Tools used
Tools used