Updated 22 Mar. 2000

Tips and tricks



  1. Your locomotive(steamers) have only 1 lamp, but your decoder has two outputs !
  2. The front lamp and the connection to the smoker are connected, how do you separate them ?
  3. How to solder on K-Track !
  4. Problems with Locomotives stopping at points in the track
  5. Have you got a dead 6090, and need components to fix it ?
  6. WHITE Light Emitting Diodes(LED) are now available !
  7. Having trouble with old turnouts connected to a K83 or single turnout decoder ?
  8. Retrofitting old lamp-sockets with the new type of pin-connector
  9. Reliable changing of signals/turnouts with contact-tracks(by Dion Stevenson)


Do you have tips you want to share with me/others ?
you are welcome to mail them to me.
Send the mail with the subject "Tips to add".
You will of course be fully credited for your entry.


TIP No # 1. - Function outputs and lamps

Sometimes when you convert an old steam locomotive, you discover that it has only one

lamp in the front. Your decoder has outputs to a front and a back light, so what do you do ?.

You connect both outputs through diodes to the lamp. This way when you activate the function,

the light is ON no matter which direction the locomotive travels.

How to connect :

For diodes use : 1N4001 or 1N4148. (other 1N400x can also be used)

The Diodes can be omitted(not recomended) - they are used to protect the outputs of the decoder.


TIP No # 2. - Smoke problems

On some steam locomotives the tongue to the smokegenerator, are connected to the front-

lights. Now that the new decoders are available it would be nice to control the smoke independently.

If it's not possible to isolate the "smoke-tongue" from the lamp, you must take other measures.

Get a small piece of printed circuitboard and glue it to the tongue. You can then solder a small

wire to the circuitboard, and voila ! - you can now control lights and smoke independent.

 A childlike drawing to illustrate :

 And some pictures to back it up :




TIP No # 3. - Soldering on K-Track

If you have a large layout its recommendable to have several power connections to your track.

But what do you do with those pesky K-Track, - They seem impossible to solder on.

Don't despair, its actually quite simple.

For connection to the center rail, solder your wire to the bottom side of the small tongues.

For the connection to the rails, solder your wire to the side of the small "connector" which

connects the track-piece to the next.

Be carefull not to use to much solder, as this can ruin the small tounges, and stop them form working properly

TIP No # 4. - Slider Problems

If you have problems with locomotives that stops at eg. turnouts, because the slider bumps against

the studs, Alan Pearce from the Märklin Mailing list brought out a suggestion :

"I always adjust the shape of the slider portion of the pickup shoe so it is
ever so slightly concave to minimize this problem. It can be an even worse
problem with a loco like a Glaskasten which moves slowly at even its top
speed, and does not have the mass to keep momentum up if it does manage to
loose contact. You need to be very careful about just how much you try to
make it concave 0.25 - 0.5 mm should be more than enough."


TIP No # 5. - Spareparts needed !?!

If you got a dead 6090 where the 701.13 chip is damaged, you could see if you can get your

hands on an older Delta(6603)-decoder. Just grab the chip from there.

P.S this will require good soldering skills.

(tip provided by Andreas Priebe )


If you need a replacement for the BST51 power-transistors, Hans-Peter Henkel may be

able to help you :

 "Repair of malfunctional light output"

Replacement transistors BST51for decoders 6090 and 60901
and 6080 are available for 3€ / 10pcs. + postage via
Hans-Peter Henkel across Europe.
mail contact : hphenkel@e-sm.de


TIP No # 6. - Using White LEDs

If you have rolling equipment who uses yellow LEDs as front light, you will be pleased to

know that you now can get white LEDs. The are very bright and can easily replace a lightbulb.

They use a higher voltage that the normal LEDs, so the resistors, who normally are in series with

the LED, needs to be lowered. The white LEDs are available in both 3 and 5 mm.

The only real bad thing about them is the price. They are 10-15 times more expensive than normal

LEDs - aprox. 5-7$.

An example of locomotives that use yellow LEDs, and could benefit from a conversion to white

LEDs are those manufactured by Electrotren.

 For pictures, Guides and more info - Click here

 Technical data :
 Typical Voltage  3,6 volt

 Calculation of resistors :

(Supplyvoltage - LED-voltage)/LED-current = Resistor

Example : Supply-Voltage = 20 Volt ,LED-Voltage = 3Volt

LED-Current = 20mA => (20V - 3V)/0,02A = 850 Ohm.

Use 0,5-1 Watt resistors (the above uses 0.34 Watt)

 Max. Voltage  4 volt at 20 mA.
 Max. Current  25 mA.
 Light Strength max. 2000 mcd - Typical 400 mcd
View Angle  60 Degrees
 Life Span  60.000 - 100.000 Hours (7-11 Years)


TIP No # 7. - Turnout problems

If you have old or bad-switching turnouts connected to a decoder such as the K83 or

the single(6073) , you may experience problems, like the turnout won't change all the way over.

Of course this problem can be caused by dirt in the mechanism, and can therefore be solved

buy cleaning.

Some turnouts may switch slowly because there is not enough power available to drive the

mechanism properly. This can to some extend be solved by adding a larger capacitor to the

box/decoder. the one that needs to be changed are the largest one you can see on the circuitboard.

In the K83-box the present value are 220uF/25Volt. This value should be increased. There is

no max-value, but I don't recommend higher value than 1000uF - there is also the problem of

fitting a larger capacitor in the box.

I recommend a value of 470uF/25V !.

Simply de-solder the existing capacitor and solder in the new one. Just be aware of the polarity.


The 6073 uses a smaller SMD capacitor, which is placed between the two larger chips.

Here you cannot just de-solder it and replace it with a larger one, as it probably won't fit !

Adding more "capacity" is simply a matter of putting more capacitors in parallel.

A solution would be to solder two small wires to the poles of the SMD capacitor, and

solder them to a capacitor placed away from the circuitboard.

To figure out what value you end up with, simply add the values of the capacitors.

The present one is 22uF, and if you add a 220uF, the combined value will be 242uF.

Again remember the voltage (25Volts) and the polarity ! !

DON'T put capacitors in series as it will DECREASE their combined value, - using the

above values , the two capacitors in series will end up with a value of 20uF ! !.


TIP No # 8. - New Lamp-Sockets

If you run digital, it's easyer to remove flicker if you have the new type of bulb-sockets, because

the lamp does not have a permanent connection to the chassis.

BUT - You can retrofit a new bulb-socket yourself.

You buy the sockets as a sparepart (259220 or 604180), and mount them !.

You may have to work a bit with a drill and a file, in order to fit them.

 The two types to chose from

 The 604180 mounted in a 3034(E141)




TIP No # 9. - Reliable Contact-tracks

When you use contact-tracks to change signals and turnouts, you may experience, that the pulse

the train generates through the contact-track is not long enough to change the signal/turnout.

Dion Stevenson has come up with a small electronic circuit, that prolongs the pulse from

the contact-track, to insure reliable switching.

The files are in PDF, and requires an acrobat reader. I f you don't have one download it here

 Click on the pictures to download the PDF-files



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If you have a question about anything I have written, then send me a mail

Email :kenneth@pallund.dk