Thinking about switch control on main layout

So, the decision I made a couple of days ago to go with Tortoise switch machines on the main layout sparked my thinking about the whole switch control issue. This isn't a new issue at all, but sometimes you need a spark to help you finally reach a decision.

I researched the docs at Digitrax, skimmed various web sites, and started an email discussion with Mike Gleaton at Charleston Digital Trains, who is my primary source for DCC paraphenalia due to his extensive helpfulness and responsiveness, not to mention his ultra-competitive prices.
Long story short, the solution seems to be the Digitrax DS64. Yes, I knew the DS64 could provide digital control of 4 switch machines (either slow motion or snap relay), but at $48 + shipping I was hoping for something cheaper. But here's what I learned are its advantages:

1. Meets requirement: It can use a non-track power source. This is important because otherwise a large number of stationary decoders can drain the track power, requiring boosters and potentially interfering with train operations. A single PS12 power supply ($8) can power 20 DS64s, possibly more.


2. Meets requirement: There are slots for additional input devices, such as a fascia board with switch controls. This is huge -- I thought I'd have to buy separate DCC devices to support this feature.


3. Meets requirement: The DS64 supports 8 routes. Now, I've known this since I first read about the DS64, but I didn't really think about it until now. You really do want routes for things like ladder switching, because otherwise instead of clicking one logical switch for the track you want to go to, you have to click all the switches in between. The idea of one-click switching is helpful both for manual switching boards and for simplifying dispatching for a large layout.
   
   But if you have a lot of switches you'll need lots of routes. For example, a single 5-track yard with switch ladders at both ends will require 10 routes -- two (one for yard entrance, one for yard exit) routes for each of 5 tracks. The biggest Digitrax command station, the DSC100, which I have, supports only 32 routes. Each DS64 adds 8 routes, twice as many as the number of switches it supports, and since the routes can include switches attached to any DS64, a layout full of DS64s gives you more routes than you can realistically use, even if you use the "virtual" route addresses that Digitrax suggests for special switch situations.


4. Meets requirement: It has sensors to provide feedback to the command station, the computer, and the fascia switch board indicating the position of the switch.


5. Very useful: The DS64 can be configured to turn power off to the Tortoises 16 seconds after the switch movement is finished. This isn't true for all layout situations, but I have found that when the Tortoise is powered off on my layout it still holds the switch points firmly against the rails, thus making continual powering of the Tortoise unnecessary. I hear that this is not always the case, but perhaps my use of thicker-than-standard gauge wire for the Tortoise makes the difference.


6. Possibly useful: The DS64 can control both snap-relay and slow-motion switch machines, but not both types from one DS64. This gives me the option later of using the same technology, the DS64, when I start adding DCC control to my staging switches.


7. Possibly useful: There are also features related to signaling, which I haven't explored. But this is a topic I want to tackle before I get too much farther along.

So, I've sent Charleston Digital Trains an order for a DS64, a PS12, and a LocoBuffer-USB for computer control. Once they arrive I'll start experimenting.