G'day ! New here! Great site, very informative! Have a few questions.

1. I have a bunch of old Marklin trains. To me, the weakest point seems to be the relay that changes the direction of the loco. There is a small spring on it. My experiences are as follows:
-spring a tad too tight ---> loco moves a bit when changing direction or doesn't change direction at all (just moves...FAST)
-spring a tad too loose ---> loco stops driving at medium speeds and hums.
I just bought an '80s model 3153 (BR120) and the sping was too tight. I have an old '60s 3921 (a kit of the V200) and I can't run it fast because the spring is a tad too loose. Same with an old 3937 (kit of the green E41). Went to an official dealer and had "the right" springs installed in each model. Things didn't improve greatly. I experiment with minute alterations to spring length and get decent results.
Any suggestions about making the relay work flawlessy are welcome!!

2. There seem to be speed drops on certain sections of the lay-out. I frequently change the lay-out (I've got a huge stack of old M-rails that I use to please the kids with, making room-filling lay-outs every other weekend) and there are always slower sections. There seems to be a correlation to distance from the transformer. Ohm's Law at work here? Resistance in the tracks? Suggestions?

Thanks for any info y'all might offer . Oh, for the model buffs, here's a list of my stuff:
2953 3003 3016 3029 3153 3366 3921 3937 4000 4002 4017 4018 4027 4041 4050 4159 4160 4506 4620 4621 4802 4903 4905 4908 4909 4912 4914

Hi Oscar, i agree with perz, to regulate the spring may be a very difficult task, but with some work you can have the locos running smoothly. The drop of tension is a kwonw fact, marklin recomend feeders every 4-6 feets.
Bye
Francisco

One of my suppliers, Kurt Bothner (Stuttgart), has loads of old (but "new") delta decoders (Märklin 6603) at 22 EUR/each on http://www.bothner-model...e/html/digitalteile.html . The result should be good in analogue mode.

Peter

There are basically 3 differences between Delta and Digital decoders:

1) Delta runs with AC motors (all-current/alternative current) - which is the same kind that is used in analogue Märklin locos. Digital decoders runs with DC motors (direct current).

2) Digital has acceleration/brake delay, which gives the trains a more realistic start and stop. Delta starts more abruptly and brakes in the same way.

3) Digital has extra function outputs for lights, TELEX, sound etc. (if these are available on the loco). Only the latest Delta decoders have outputs for light - most Delta locos have only light change with direction and light intensity changing with speed...

Besides these 3 major differences there are a few more: Digital has more addresses (80 vs 15). Digital works automatically with analogue current without setting the DIP-switches (Delta has to be set to "address 0"). And this is only the facts about the locos - the control units are very different - but compatible to some degree.

The message is - if you buy a loco, always go for Digital if you can afford it, even if you use a Delta unit on your layout!

/K-G