Digital or Delta
© 2001 Karl Jahr
You may use this information or link to it.
But you may not modify it, and the copyright may not be omitted
These questions and answers are provided as a
and not meant to be exhaustive nor necessarily without error.
If you have a comment or detect an error or omission, please send email to
my website at www.germantrains.com
Delta Control Unit: US-$ 55.00
Digital Control Unit 6021:
top of page
Delta is Märklin's least
expensive way to get into digital train control.
What does it do?
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
What do I
need for Delta operation?
A Märklin Delta control unit 6604
At least two and no more than
four locomotives that are equipped with a delta module or digital
The special "Delta Pilot" 6605 permits operation of
a fifth engine.
A Märklin transformer with
speed control dial for analog operation and an
output of 30 or more Watts.
Any kind of Märklin or Primex
by Märklin 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
stock as desired
How do I connect it?
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
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
Yes. The digital
address must be acceptable to Delta (24, 60, 72, 78) or the Delta Pilot
(80). On Märklin digital
decoders they are set by means of dipswitches. Refer to instructions.
Can conventional locomotives be
converted to Delta or digital?
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 Märklin's warranty. You must be able to solder and
understand how to protect the electronic component against static electric
shocks. Authorized Märklin 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
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.)?
No. For this you need a digital control unit and then
some. See below.
What is digital
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
There are two aspects: train control and track control.
What do I need to
digitally operate my trains
(train control)? top
A Märklin Digital control unit 6021.
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
Typical locomotives require about 8-10 Watts.
The 6001 Märklin 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 Märklin 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.
Any kind of Märklin or Primex by Märklin 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.
Optionally 6017 booster with
additional transformer for very
The Delta control unit can be used as an
inexpensive booster. See
Optionally 6051 Interface and a
computer (286 DOS, 386up with Windows). Märklin offers a track
Inexpensive shareware programs
are also available.
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.
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
provide me with a wiring chart for this great feature
Do I need to control my
electromagnetic articles digitally?
No. You can do it the old fashioned way with control
boxes. However, digital track control offers three advantages:
Wiring is less complicated.
A 6043 memory to control entire
roadways with one button
A computer can be used to control your layout
What do I need for digital track
The same Märklin 6021 Digital control unit you use for
One 6083 decoder "k83" for every four
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.
A 6040 keyboard for every 16 electromagnetic
articles. Up to 16 keyboards are permitted.
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.
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
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
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.
C-track or not to C-track? top
When Märklin 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 Märklin 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.
Moving to Marklin Digital - A
here for more information