Suzie

You can use a PL12 with the extension bar going under the track. For difficult situations make a longer extension bar, or use two! This is handy when you want to avoid framing under the point as well.

Those redundant DC portals look just like the 1940s Great Eastern ones that are now being replaced due to being end of life. I suspect they will have to go soon whether they get used or not.

You can buy an adapter from Signalist to motorise Ratio semaphores with servos which fits through the baseboard and allows the Ratio signal to just drop in to the hole for easy removal with no linkages to make.

https://www.coastaldcc.co.uk/products/harman/ratio-signal-motorising-kit

It looks good, but is probably too late in to the space that Arduino has already taken.

It will be interesting to see if Betamax beats VHS in this race!

Nothing else required, just the AC LEDs and resistors shown in the diagram.

I understand it that if you want to do DC power switching you will have to both cut some links and make some new ones.

The track plan looks a lot more complicated than it is. There were basically two loops, a 'Union Pacific' and a 'Rio Grande' with two trains running on each loop.

It certainly looked impressive and very busy.

You get four indications. Both lights on meaning the point is in a 'mid' position, and both lights off meaning there is no power to the track. This can be handy for quick fault finding.

The Hornby one should not need the link wire.

1 hour ago, angus1 said:

This has probably been discussed before but I am a new member.

I want to, (can I use), a Peco passing contact switch to activate a Dapol GWR home signal. In the new installation instructions it shows a switch diagram with the two switch wires appearing to go to one of the outer contacts and the centre common contact, leaving the other outer contact not connected. Is this correct or is it wired differently?  I want to use a pc switch to match the point switches on  my mimic diagram. Should I just use a push to make?

What is a 'pc' switch?

The diagram is correct as long as you don't use a Peco passing contact switch - the wiring for a Peco switch is sightly different.

Quite big then.

How big is 37 000 square feet compared to other similar venues? At least it will have parking.

You can buy 'AC' LEDs which are ideal for this application since they don't require the protection diodes and therefore make wiring a bit simpler for the version 1 scenario:-

Green AC LED

https://www.rapidonline.com/truopto-osggd25111e-5mm-pure-green-ac-led-22-000mcd-15-56-2309

Red AC LED

https://www.rapidonline.com/truopto-osrrj25111a-5mm-red-ac-led-5800mcd-15-56-2311

White AC LED

https://www.rapidonline.com/truopto-oswwy25111e-5mm-white-ac-led-10000mcd-15-56-2314

Blue AC LED

https://www.rapidonline.com/truopto-osbby25111e-5mm-blue-ac-led-5800mcd-15-56-2307

Yellow AC LED

https://www.rapidonline.com/truopto-osyyj25111a-5mm-yellow-ac-led-5800mcd-15-56-2316

3mm versions are available too.

DCC stay-alives work best at low speed when the motor is drawing less average current. The Zimo one in particular is excellent when the train is almost stopped since it uses the stored energy to move the train along to the first bit of live track so as to keep everything powered up.

While you might like to think of it as a flywheel it is a lot more capable than a simple flywheel, more like a flywheel with its own gearbox!

It would help really to decide to go for DCC or DC, it will save having to answer the same question twice!

Your first diagram is how you would wire it for simple DCC with Insulfrog, for DC you just would not bother with the insulated joiners. If you were doing it properly for DCC with Insulfrog you would add a few more feeds to the dead sections and insulated joiners on the frogs as you have done in the third diagram which is correct for DCC with live frogs.

Insulfrog is not like other varieties of dead frog as it needs to be treated the same as live frog when used with DCC, but retains all the disadvantages of dead frog. It will all be quite academic soon as Unifrog will be replacing Insulfrog and the problem will go away.

The new 'Unifrog' points should address these issues.

PL15 will be fine.

Yes, it looks like the MX644 has not been produced, only the 21-pin MX644C/D variant. The version with wires is the MX645 based on the PluX 22-pin decoder.

I think that F1 on an American command station is likely to be the bell. F2 should be the horn.

You will have trouble with the ZTC because of the ZTC accessory numbering not matching the standard Expressnet numbering, but other than that it should work. It will not work with NCE.

The routecontrol is best plugged in to a Lenz Expressnet panel or similar with a modular cable, and the expressnet panel can be wired to the ZTC.

1N400x diodes are 1A rating, but in a full bridge rectifier they are only in use half of the time so the bridge is 2A continuous rated when used on an AC transformer as in the H&M controllers and will handle a big surge for a short time without issue.

I would expect F1 to do the green wire and F2 to do the purple (or is it brown) wire, but it may be supplied different of course.

Rather than turn the track off, use a detector to feed back the train position to your control system, and let the control system send an emergency stop command. That way all the lights and sound will stay on!

Even that method is a bit crude. Use decoders like Zimo (and Lenz) with a fixed braking distance and when you send a stop command you know how far the train will go before it stops, and it will slow nicely to a stop.

You can also use asymmetric braking too. There are a few ways to do this in DCC.

Simple answer is :-

1. Yes.

2. You will need a module.

Now it might be worth looking to simplify things a bit. Are you simulating a signal that is actually protecting a point? If so it will sit at red until a route is set, and will return to red and stay there when a train passes it. In this case you won't need to display the yellow aspect (especially since you will not be able to send two trains in to the fiddle yard in quick succession!)

Unfortunately your requirement has a conflict in that if you want the signal to sequence to green after the train passes, what happens when you change the point to set it against the signal? It is not prototypical for a signal to go directly from green to red without a train passing - a block signal would not do this, and a signal protecting a point would not do this because a route would have to be set, and then cleared, before the point could change.

I did not know much about American railways when I visited there so it was all a bit alien, but now I realise how much attention to detail there was not just in the trains but the landscape too. It really was rather special and a sad loss.