Building the layout

I started building using a wooden board measuring approximately 120x250 cm (4 by 8 ft), and built a simple oval layout:

At least, this was my goal: it took me some time to collect all the tracks, which I bought mostly secondhand, and the turnouts were all manual at first, I added solenoid turnout switches as I went along. I had only one loco at first, and when I bought another one, I came across the first hurdle: how to control them separately. I had built only the two inner loops, so I decided to separate these with isolated joiners, and control the two loops independently, using the two transformers I had acquired. I made a small control box, and made a plan to control the turnouts with switches and LEDs:

This plan roughly corresponded with the above track plan, with an extra exit to the 'Spiraal', a helix I was planning to build later on.

The 'W' denoted the switches, and the places in the fascia where a simple sp-co switch (Single Pole – Centre Off) would come, with a neutral centre as the only stable position, so I could use it as a pulse switch to control the turnout coils. For the leds on either side of the switches, I used the following circuit:

This only works because the Fleischmann turnout solenoids have an end-off feature, that connects one of the poles to the centre connection, but it makes things easier. Assembling this was mostly a mechanical issue: plug the LEDs in holders that require a simple hole in the fascia, mount the switches, and solder the resistors directly to the switches and LEDs.
I also added three other sp-co switches with three stable positions, to connect the inner and outer loops of my layout to the two different transformers. This way I could turn a loop completely off, or connect it to either of the transformers. I became very fond of all these sp-co switches, and I looked for other ways to use them. Lastly, I added a switch to turn on the lights, for the houses and street lights on the layout.

All this required little or no electronics, but of course things progressed rapidly from here on: for example, I wanted to add a helix leading to a 'shadow station', and this required a reversing loop. Since I was using a DC 2-rail system (Fleischmann mostly), this meant some kind of reversing circuit was needed. I solved this using the standard Fleischmann diode-isolated track pieces:

But this works with serious disadvantages: the loco can only run one-way, and of course you have to reverse direction while running inside the loop to get the loco out of the loop. And this trick only works with DC, for digital signals this is useless.