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Frequently asked questions about Marklin Digital and Delta Systems


Did you know that?
Delta controls can be used as inexpensive boosters!


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FAQ on Marklin?p> Digital or Delta
?1 Karl Jahr
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Marklin Delta Control Unit: US-$ 55.00

Marklin Digital Control Unit 6021: US-$250.00

What is Delta?        top of page

Delta is M?lin's least expensive way to get into digital train control. 

What does it do?    top of page

It permits the simultaneous independent operation of up to four locomotives which must be equipped with either a delta module or a digital decoder. A special hand-held "Delta Pilot" allows for the control of a fifth engine.  The symbols on the Delta control unit correspond to the following addresses: Steam engine: 78; Diesel engine: 72; Motor train: 60; Electric engine: 24. The "Delta Pilot" requires the address 80. 

What do I need for Delta operation?   top of page

  1. A M?lin Delta control unit 6604

  2. At least two and no more than  four locomotives that are equipped with a delta module or digital decoder.

    The special "Delta Pilot" 6605 permits operation of a fifth engine.

  3. A M?lin transformer with speed control dial for analog operation and an output of 30 or more Watts.

  4. Any kind of M?lin or Primex by M?lin track as long as it is clean. 

    Note: If the feeder track is equipped with a capacitor, you must remove it for delta and digital operation.

  5. Rolling stock as desired

How do I connect it?   top of page

The Delta control unit sits between the transformer and the track. Follow the instructions that come with the unit.

Can I run conventional (analog) locomotives on a Delta or digital layout?  top of page

No. Digital systems have a constant 16 Volt power on the track. Conventional locomotives would therefore run uncontrollably at constant speed.

Can I run  locomotives with the digital decoder on a delta system? top of page

Yes. The digital address must be acceptable to Delta (24, 60, 72, 78) or the Delta Pilot (80). On M?lin digital decoders they are set by means of dipswitches. Refer to instructions.

Can conventional locomotives be converted to Delta or digital?   top of page

Yes. You either need a 6603 or 66031 delta module , or a 6080 digital decoder "c80" . Doing it yourself is no rocket science, but it voids M?lin's warranty. You must be able to solder and understand how to protect the electronic component against static electric shocks. Authorized M?lin dealers can do the conversion for you. Delta modules are cheaper and make sense for most conversions.

Can I run Delta or digital locomotives on a conventional (analog)  layout?   top of page

Yes. Depending on the model of the decoder, the engine will either automatically recognize the analog mode, or you would have to set dipswitches on the delta or digital module to analog operation, in which case it would become an analog locomotive. (But who would want to do this anyway?)

Can I use Delta to control electromagnetic articles (turnouts, signals, etc.)?   top of page

No. For this you need a digital control unit and then some. See below.

What is digital operation?   top of page

Digital operation goes beyond Delta's capabilities. You can independently control up to 80 locomotives and up to 256 electromagnetic articles (turnouts, signals, cranes, turntables, etc). You can also use a computer to control the operation of trains and  electromagnetic articles. 

There are two aspects: train control and track control. 

What do I need to digitally operate my trains (train control)? top of page

  1. A M?lin Digital control unit 6021.

  2. At least two and no more than 80  locomotives that are equipped with a 6080 or equivalent digital decoder.

    Up to 15 of these engines may have a delta module instead

  3. Typical locomotives require about 8-10 Watts. The 6001 M?lin  transformer is specifically designed for digital operation and provides output of 42 Watt, but an older analog transformer can be used as well for smaller layouts. If you have a 220 Volt European transformer (e.g. the 6002 M?lin transformer with 52 Watt of output) for use in North America, you need to buy a 120 to 220 Volt step-up transformer from Radio Shack for about $30-35. The difference in AC cycles (i.e. 50 Hz in Europe, 60 Hz in North America make no difference) 

    If you use an older analog transformer you must set the speed control dial to full speed.

  4. Any kind of M?lin or Primex by M?lin track as long as it is clean. 

    Note: If the feeder track is equipped with a capacitor, you must remove it for delta and digital operation.

  5. Optionally 6017 booster with additional transformer for very large layouts

    The Delta control unit can be used as an inexpensive booster. See below.

  6. Optionally 6051 Interface and a computer (286 DOS, 386up with Windows). M?lin offers a track control program. 

    Inexpensive shareware programs are also available. 

  7. Optionally additional 6036 control 80 f to have more than one dial for train control 

    Not necessary, you can share the dial of the 6021. May be convenient if more than one person is operating the layout.

The Delta Control 6604 can be used as an inexpensive booster

For large digital layouts the power provided by the 600x transformer and the 6021 central control may not be enough. A booster is required in this situation. A well concealed secret is that the Delta control unit, together with a Marklin transformer that delivers a maximum of 32 Watts, can be effectively and inexpensively used as a booster. (Note: A 10 or 16 Watt transformer may not be sufficient in most cases). 

Please provide me with a wiring chart for this great feature

Do I need to control my electromagnetic articles digitally?  top of page

No. You can do it the old fashioned way with control boxes. However, digital track control offers three advantages:

  1. Wiring is less complicated.

  2. A 6043 memory to control entire roadways with one button 

  3. A computer can be used to control your layout

What do I need for digital track control?   top of page

  1. The same M?lin 6021 Digital control unit you use for train control

  2. One 6083 decoder "k83" for every four electromagnetic articles. 

    For the new C track you can also use one decoder 74460 for every electromagnetic article (this makes wiring a snap because you don't wire anything). An elegant, but expensive solution.

  3. A 6040 keyboard for every 16 electromagnetic articles. Up to 16 keyboards are permitted.

  4. Optionally a 6043 memory that permits to turn entire sequences of up to 20 electromagnetic articles with the push of one button. Each memory permits control of up to 24 such sequences, and you can use up to 4 memory units. This reduces and even may eliminate the need for 6040 keyboards.

  5. Instead of using keyboard and/or memory you can also use a 6051 computer interface with a low powered (286/386/486 DOS or Windows computer) and an appropriate program. Marklin offers the 60511 "Comboard" track control program. 

    Because of the rather high cost of the keyboard (one for 16 turnouts!) this becomes economically very feasible - an old computer doesn't cost even what a keyboard costs.

    There are also programs that permit you to perform train control, but you still need the 6021 control unit. I use one of these programs with a 486 laptop.

Now, how the heck does this work?   top of page

    Train control   top of page

Let's start with conventional (analog) systems: As you turn the dial on the transformer, you control the speed of the engines by varying the voltage to the engine. When your transformer is in the Null position, there is no voltage on the track, and when you give the reversal impulse, a sudden 24 Volt jolt cause change of direction. All engines on the same circuit act uniformly; i.e. they all run at same speed or all stop, and the lights of the trains vary with speed and are off when the train stops. Electromagnetic articles  are operated by sending a short 16 Volt impulse to turn them.

Digital systems work differently: The control unit receives constant 16 volts at the normal frequency of 60 cycles (Hz) from the transformer and converts it to 16 volts at 400 cycles. This constant power is fed to the track. It does not power the engines directly. Instead, when you turn the dial on the control unit you send an electronic signal to the decoder or delta module of the selected ("addressed") engine. The decoder then internally regulates the voltage that reaches the motor, or executes the reversal command. It thus pretty much behaves as a real engineer would by opening or closing the throttle. Additional functions can be invoked to turn on lights, sound the horn, etc. Because of the constant power on the track, all train lights will burn constantly. Special "function keys" on the control unit (f1 through f4) can be used to invoke additional functions such as lights on/off or sound.

You now probably understand why conventional (analog) engines run at constant speed on digital layouts. They receive constant 16 volts, with no possibility to either stop them (except with the emergency off button that stops everything) and no possibility to give the forward/reverse impulse.

Delta systems work similarly, except, that the Delta control unit receives variable analog power and the forward/reverse jolt from the transformer and translates it to constant digital power and creates the digital commands that are sent to the delta module or digital decoder on the engine. Again, lights burn constantly, but there are no special function keys, which means that engines with digital decoder and special functions cannot take advantage of this feature when run in Delta mode.

   Track control   top of page

All electromagnetic articles are constantly connected to the digital power. The keyboard (or computer) which is connected to the control unit sends digital commands to the system, and since each electromagnetic article has its own address, it will recognize only commands that are directed to its own address, ignoring all others. The 6083  or 74460 decoders are the traffic cops that control all this.

To C-track or not to C-track?   top of page

When M?lin introduced the digital control capabilities, they also introduced the new C-track, claiming that it provides better and more reliable operation for digital layouts. At the same time it simplifies wiring, because all that's needed is two wires from the transformer to the control unit and two wires from the control unit to the track. All electromagnetic articles, through their decoders, are directly connected to the track and therefore do not require any special wiring. Certainly a big improvement, particularly if you tend to often dismantle or change your layout. But all turnouts come for manual operation. A separate solenoid (electromagnetic device) needs to be installed for remote control, and then - for digital train control -  one also needs to install one 74660 decoder for every turnout. This quickly becomes quite expensive.

Even though there are adapter tracks from C-track to M-track and the less used K-track, the geometries of the two (three) different track systems really don't match very well, and it is difficult to come up with practical mixed-track layouts, unless one has one part of the layout of one kind and the other of the other kind, with few interconnections. Both M-track and C-track that are reliable for analog operation are also suitable for digital operation. And their turnouts are usually equipped with an electromagnetic device for remote control. - There is a very active market of second hand M-track (less so for K-track), which is fed by more than 50 years of production. So, even though M?lin has indicated that they will soon discontinue M-track, what's out there will meet your needs for a long time to come. 

So what should one do? If you start with a new layout and don't have the older track, and money is no issue, you should start with C-track. The simplicity of wiring is certainly a big plus. On the other hand, if you already have a lot of M- (or K-) track, or if money is an issue, then stay with M (or K) and keep expanding it. Whatever you choose, remember www.germantrains.com can get more of it for you. 

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