Flextrack is amazing

Once I figured out how to use the flextrack options in XTrkCAD, laying track made a lot more sense and was much more fun. The trick was to turn off easements. Easements are very prototypical. When you need to make a curve, the radius is gradually lowered, i.e. the curve gradually becomes sharper. In the real world, this prevents sudden movements when entering a curve and is used for streets and railroads alike.
However, I just don't have the space on my layout to do them properly, so regular curves have to do. Once I did that, laying flex track quickly was super-easy. The result is most visible in Talheim where I redid pretty much all the trackage. My goal was to allow for more shunting in this small station right in front of the operator, so I added a third track, and set up the tracks to resemble a timesaver. I would have liked the industrial spur to be a little bit more complex but again, limited space made this hard, given that I need to convey a believable sense of place for the industry. Depending on how the track alignment will work out in the end I might have enough space to do something more interesting, but still operable.

I'm still toying with the idea of controlling all switches and signals digitally, but this does become quite expensive, and I'm more interested in getting a train to stop automatically before a red signal (Hp0) with decent deceleration before the signal. This alone means I have to make a decision whether I want to use Maerklin's Motorola format, or switch to DCC and accept that any digital Maerklin loco I'd buy in the future would have to get a multi-protocol decoder.

Uhlenbrock 75200 in Maerklin 3075, BR 216

I tried my first conversion of an analog locomotive to digital today. For this first time around, I made it easy on myself and used a decoder that is specifically made for Maerklin AC motors (Uhlenbrock 75200).

The photos show the locomotive with the cover removed before and after the conversion.



The motor has 3 arms and thus runs not quite as round as the BR 86 I have. However, this is my first conversion, I didn't break anything and the locomotive ran on the first try. What else can you ask for?

Musings on a plane

I'm on a flight to Zurich, Switzerland, reading Tom Friedman's "The world is flat". Stories of how virtualization makes travel less necessary. How people around the world can easily interact over the Internet. How time zone differences make it possible to easily have work happen 24 hours a day. And I experience all of this in my daily worklife. However, still, here I am on my way to Switzerland to meet with all my team mates in person, because there's no better way to build and manage personal relationships than face to face meetings.

Yes, you might be able to conduct business efficiently and effectively using "the power of the net". I find IRC and individual chats an amazingly effective medium for coordinating and collaborating with co-workers around the world to work together and solve problems. The expert on a specific part of the system might not be in my office, but I can quickly loop them in to help me debug an issue. In other situations, just asking a question on an IRC channel, or web based forums, often gets me a correct and complete answer, or pointers to documentation, faster than trying to use my favorite search engine and digging through results (yes, that's ironic, showing there's still plenty of room for improvement in search engine technology...)

However, I also find that oftentimes the most value-add happens after you leave the conference room, in hallway conversations. When you run into someone by accident. When you thought about a topic for a few more minutes and then pop over to the other person's desk for a follow-up. This personal interaction is very hard to harness in a virtual environment, particularly if people work in a regular office, instead of tele-commuting. In some teams I worked with there is zero "virtual socializing", idle chatting on an open IRC channel, with random work-related comments. In other teams, such channel forms the life-blood of the team. It's the way how a globally distributed team keeps its act together and it's amazing to watch when it works.

...

When it works, you come to work in the morning, India is still awake, Europe getting close to the end of their day, the East Cost is ready to go to lunch, and you are getting breakfast. As the day progresses, Europe signs off (aside from the few night owls that apparently can never leave their computer screen before 10 or 11 pm local time) and you are getting lunch. While the early birds in East Coast offices are starting to prepare to go home at the end of their day, IM status of the first Australians becomes green and you spend the afternoon coordinating projects with your counter-parts in Sydney and then, shortly before you leave for the day, Tokyo. As you go to bed in the evening, India wakes up, and a little later around midnight, the workday in Europe picks up again. When it works, there is always someone from your team online, somewhere in the world who knows the answer to your question, or knows where to look. When it works, it's an amazing experience.

To make it work, you need continuity and critical mass. I think continuity happens by having globally distributed teams that are big enough to help each other locally in a pinch (as well as build and promote a local flavor of the team's culture), but small enough to not be completely self-sufficient (since then they have less motivation to seek out the connections with people outside their office). The critical mass is important in a specific way: If everyone spent all their time on "keeping the channel alive" no work would get done. The socializing aspect is important for team culture. Some people are better at this than others, and there need to be enough people that can keep the chatter and banter going from the random idle time people spent on "something" between tasks.

In terms of technologies I haven't seen anything that beats IRC (Internet Relay Chat). IRC has been around for many years, is amazingly robust, quite easy to administer, and almost trivial to get going. People with a minimum amount of Linux foo can set up a company internal IRC server in no time. IRC has well defined, and well known APIs, that are quite easy to use, so there exist tons of add-ons. It's major drawback is that IRC is not sexy. It's text chat. The clients usually don't look pretty. There's no support images, audio, video, ... but, on the other hand, all that stuff makes other systems more complex and prone to failure. I really don't care that much if I can see my co-worker, as long as I can get my problem solved. Video conference systems tend to work better and are more effective for virtual meetings than desktop conferencing software, especially if they involve more than 3 or 4 locations.

Bottom-line, I like both worlds, but for different reasons. Many relationships that started in face to face meetings, are kept alive and strengthened with regular interaction. People want to communicate. The easier one makes it, the more they are going to use whatever method is available.

Marie arrived in Mexico...

... and chronicles her travels at marieunterwegsinmexiko.

BR 86 and Ground

My digital BR 86 doesn't run very cleanly. Uwe's blog entry has a nice description of the problem, as well as my forum post. I tried the remedy today, but have trouble getting the wires connected properly to motor ground. Whenever I connect the wires to the ground screw on the motor shield the decoder stops accepting any commands. Need to try a bit more...

Update:

And I did try a bit more. Turns out that the screw on the motor shield is intended to connect the decoder ground to the chassis. It's not long enough to go trough the motor shield to the chassis if you squeeze in a cable because you are too lazy/scared to solder in tight quarters around the motor. Once I got over that, I soldered the cables straight on the existing solder spot and voila, the locomotive now runs just fine over those critical switches where it lost contact to ground before.

More thoughts on how to control trains

I'm still trying to figure out wht I really want. Use advanced features to control trains, or keep things simple and economical (so I don't need computer assistance).

While I don't really want to write software (no time to do this right), using computer control sounds very sweet. This would require I stick s88 control points at every switch and track that will hold more than one loco.

The first problem is how to identify locos. There are several commonly used methods:

• Cut one rail of Maerklin K track and use the loco and car axles to bridge the cut. This is very common, and well supported with s88 modules. The drawback for control is this method can't differentiate between locos and cars, and I have a bunch of M-track on my layout.
  
• Use a powersensing circuit to identify if a section of track is occupied by a train, and hook that up to the digital system. This works but isn't well suited for control because it's not very location aware. However, it's good for use in hidden staging to figure out which tracks are occupied by a train.
  
• Use a s88 control point that is trigger by the power pickup shoe of the loco. There are contact tracks made by Maerklin, as well as several build-it-yourself approaches. This works well for control if you mainly run freight trains. The method can't differentiate between the pickup shoe of the loco, and a pickup shoe, that e.g. powers lights in the passenger cars, or the rear illumatination of a freight train.
  
• Use reed contacts between the rails and a little magnet on each loco. This method clearly identified locos. However, each s88 contact needs to be made from reed contacts which are visible between the tracks and cost additional money, and each loco needs to be fitted with two small magnets.
  
• Uhlenbrock offers LISSY which is a digital control system to solve the problem. It's clearly the most complete and powerful solution, but also the most expensive.
  

In what situations do I need digitally controlled stops?

Stop a train before a signal that shows red automatically.

• Trains should stop in front of a red signal and preferably decelerate before coming to a stop.
  
• Most digital locomotives don't roll very far when the loco looses power, so I don't really want to run them into section of track with no power (like in the old analog days).
  
• On a green signal the train should accelerate automatically.
  
• lights and functions should remain on while the loco is stopped.
  

Digital model railroading for real now

The Intellibox and transformer finally arrived after many shipping delays. After dinner I set up a little bit of track on the dining table and connected everything. My only digital loco BR86 was used as guinea pig. Low and behold, as soon as I set it on the track it ran. It still remembered the speed setting from the store when I tried it out. With some trial and error I figured out the loco address, and was able to control all functions from the Intellibox with minimal fuss. The one irritating thing is that the speed steps are extremely coarse. At step 1 the loco creeps along, step 2 it moves ok, step 3 it feels like full speed, but there are 14 steps total. I need to find a way to reprogram the speed range on this decoder. Looks like it's a fairly new Marklin mfx decoder, which is not supported for programming on the Intellibox. Bummer.

Speaking of which, the connector on the Marklin transformer I got is amazingly whimpy and easily slips out. Not very convincing.

Mit viel Verspaetung kamen heute die Intellibox und der Trafo an. Gleich nach dem Abendessen habe ich alles angeschlossen, etwas Schienen aufgebaut, und die BR86 als Versuchsschweinchen auf das Gleis gesetzt. Zu meiner Ueberraschung fuhr sie auch gleich los. Sie hatte noch die Geschwindigkeit und Richtung gespeichert von als ich sie im Laden ausprobiert hatte. Mit etwas Rumprobieren bekam ich die Adresse des Dekoders heraus und konnte die Lok problemlos mit allen Sonderfunktionen steuern. Das einzige Problem ist dass die Geschwindigkeitsstufen des Dekoders zu grob sind. Bei Stufe 1 kriecht die Lok. Mit Stufe 2 geht's ganz gut, Stufe 3 wird schon recht schnell, insgesamt hat die Lok aber 14 Stufen... Das muss ich noch in Ordnung bringen. Die Intellibox understuetzt aber nicht das Umprogrammieren von mfx Dekodern. Mal sehen...

Der Stromstecker an dem Maerklintrafo rutscht sehr leicht ab, und ist erstaunlich instabil. Nicht ueberzeugend.

tcp window scaling, Linux, and broken routers

So, what the hell is TCP window scaling and why do I care?

This had me puzzled for a few days: solarguard.solarcity.com worked fine when I was working from my laptop from home, but didn't when I was at work. That's the Web site the monitoring data from my solar panels is sent to.

At first I thought they don't support path MTU discovery properly (e.g. by blocking most icmp packets, including "fragmentation required"). However, lowering the MTU on my workstation didn't help (but it briefly messed up NFS...)

A co-worker pointed out a the Web site doesn't support Linux, but works fine with Mac and Windows. Bullocks, I thought, silly browser requirements. However, sure enough, even a simple "GET / HTTP/1.0" sent via telnet from Linux doesn't work, but works fine from my Mac laptop. I was stumped.

Until I did these two tcpdumps of a telnet session to solarguard.solarcity.com.

21:09:37.486875 IP bbeck-mac.wlan.lostentry.org.50292 > sol6.solarcity.com.http: S 3232032404:3232032404(0) win 65535 
21:09:37.502028 IP sol6.solarcity.com.http > bbeck-mac.wlan.lostentry.org.50292: S 3190318898:3190318898(0) ack 3232032405 win 16384 
21:09:37.502098 IP bbeck-mac.wlan.lostentry.org.50292 > sol6.solarcity.com.http: . ack 1 win 65535 
21:09:43.279950 IP bbeck-mac.wlan.lostentry.org.50292 > sol6.solarcity.com.http: P 1:17(16) ack 1 win 65535 
21:09:43.476237 IP sol6.solarcity.com.http > bbeck-mac.wlan.lostentry.org.50292: . ack 17 win 65519 
21:09:43.616030 IP bbeck-mac.wlan.lostentry.org.50292 > sol6.solarcity.com.http: P 17:19(2) ack 1 win 65535 
21:09:43.632860 IP sol6.solarcity.com.http > bbeck-mac.wlan.lostentry.org.50292: FP 1:559(558) ack 19 win 65517 
21:09:43.632967 IP bbeck-mac.wlan.lostentry.org.50292 > sol6.solarcity.com.http: . ack 560 win 65535 
21:09:43.633327 IP bbeck-mac.wlan.lostentry.org.50292 > sol6.solarcity.com.http: F 19:19(0) ack 560 win 65535 
21:09:43.650105 IP sol6.solarcity.com.http > bbeck-mac.wlan.lostentry.org.50292: . ack 20 win 65517 

and

21:14:19.460778 IP chef.lostentry.org.56146 > sol6.solarcity.com.http: S 3539793334:3539793334(0) win 5840 
21:14:19.474075 IP sol6.solarcity.com.http > chef.lostentry.org.56146: S 3721548036:3721548036(0) ack 3539793335 win 16384 
21:14:19.474105 IP chef.lostentry.org.56146 > sol6.solarcity.com.http: . ack 1 win 365 
21:14:24.092355 IP chef.lostentry.org.56146 > sol6.solarcity.com.http: P 1:17(16) ack 1 win 365 
21:14:24.238705 IP sol6.solarcity.com.http > chef.lostentry.org.56146: . ack 17 win 65519 
21:14:24.844354 IP chef.lostentry.org.56146 > sol6.solarcity.com.http: P 17:19(2) ack 1 win 365 
21:14:30.238534 IP chef.lostentry.org.56146 > sol6.solarcity.com.http: P 17:19(2) ack 1 win 365 
21:14:30.263687 IP sol6.solarcity.com.http > chef.lostentry.org.56146: . ack 19 win 65517 
21:14:30.263723 IP chef.lostentry.org.56146 > sol6.solarcity.com.http: P 19:21(2) ack 1 win 365 
21:14:30.476289 IP sol6.solarcity.com.http > chef.lostentry.org.56146: . ack 21 win 65515 
21:15:59.668923 IP chef.lostentry.org.56146 > sol6.solarcity.com.http: F 21:21(0) ack 1 win 365 
21:15:59.680890 IP sol6.solarcity.com.http > chef.lostentry.org.56146: R 3721548037:3721548037(0) win 0

What is up with the tcp window size in the Linux dump once the connection is established? 365, vs. 65535 on the Mac. And what does wscale do?

This made me suspicious and a quick visit to our favorite search engine brought up this most excellent blog entry, as well as a somewhat old article on LWN which, however, explains he basic technicalities quite well.

In a nutshell: TCP window scaling is used to work around limitations in TCP that restrict the maximum window size to 64kBytes, by negotiating a multiplier for the window value during session setup. Apparently, there are some broken routers out there that set the wscale option to 0, effectively transparently disabling window scaling without telling anybody. The result are TCP connections that appear to hang for data, but control traffic (like syn/ack, rst, retransmit, etc.) still works!

Sure enough, if I disable TCP window scaling on chef, the SolarGuard website sends the response just fine even in a telnet session, where it didn't work before. Setting the tcp_rmem and tcp_wmem values to the pre-2.6.17 values makes this work properly even with window scaling enabled.

I left window-scaling enabled, but manually set

sysctl -w net.ipv4.tcp_wmem="4096 16384 131072"
sysctl -w net.ipv4.tcp_rmem="4096 87380 174760"

and the Website works fine now.

As an aside, kudos to SolarCity staff. I called Support, they forwarded my problem to someone in Engineering, and I had a sensible answer in my inbox in less than 20 minutes after my initial problem report, followed up with a confirmation that they verified connectivity from multiple places and networks without problems. They even confirmed that my box is working properly.

Maybe they happen to have control over that old router that is not compliant with RFC 1323 from the year 1992, and either fix it, or take it out back and shoot it...

Update:

In Windows the registry key HKLM/tcpip/parameters/Tcp1323Opts is a bit field that controls whether tcp window scaling is enabled (1) or not (0). Setting this to 0 disbles tcp window scaling for both incoming and outgoing connections.

Windows Vista has tcp window scaling enabled by default (so it will have the same problems, that I had with Linux). It can be turned off using the network tuning wizard, or above registry key.

SolarCity SolarGuard

A couple days ago, SolarCity came out and installed the SolarGuard unit. With my Xantrex inverter they can install it straight into the cabling box. It connects via serial port to the inverter and reads the status every few minutes.

The unit itself is actually quite small.


From the outside only the antenna indicates that this inverter is enabled for remote monitoring. I have quite some concerns how long this antenna will last, given that the inverter is in the side-yard of the house and we regularly run trashbins and stuff right by it. To reduce the likelihood of damage to the antenna I turned it side-ways against the recommendation of the technician.


The unit in the inverter communicates with a base station that is connected to my network. The wireless connection doesn't show up when looking for regular wireless networks. I suspect they are using ZigBee (802.15.4) for this link.

Train "Room" Update

The train "room" in the garage is taking shape. The platform frame is done and level. I built this from the faux beams left over from last summer's Asbestos action. The floor is 3/4" plywood supported by 2x4 joists and some additional left-over wood pieces. The whole platform is screwed together, so I can disassemble it easily, if ever necessary.

The final size of the room is 8ft by 8.5ft (240 x 255cm). When I looked at the layout plan I realized that I was working with 240x220cm. I just gained a full 240x40cm of space, which allows me to decompress the whole layout quite a bit.



PDFs: Upper Levels - Lower Level

Underground staging gained a forth track. The ramp to staging got longer, with less grade. I also managed to correct an earlier mistake with where I would place the transition track between K and M tracks.

I angled the Emsingen station at only 15 degress now, which makes for a better flow of track and at the same time moved the station a bit north to have more space in the center of the layout. I could even squeeze in another track to keep cars at the station overnight. The (otherwise flawless) Maerklin track geometry isn't quite accomdating with the 105 degree turn I needed on the West side of Emsingen station, so I will need to fudge a little bit here using flextrack.

Having a deeper northern portion of the layout presents serious access problems, escpecially because I will have track underneath Emsingen station in all the places where one would want to place an easily accessible access hatch. I'm currently planning to make the area around the Emsingen station building removable, so that I can access the north end of the layout.

The tunnel ramp from Emsingen West down the east side of the layout around the mountain has exactly the same grade and location as the respective ramp underneath to staging. I'm planning to build the staging ramp solid enough so that I can simply build the Emsingen tunnel ramp on top it.

I'm not quite sure yet how to arrange trackage in Talheim. Would be nice to connect the two industries in a little bit more prototypical way. I also have a lot of tunnels on this layout, so I want to make sure that the visible track is as conducive to train watching as possible (wide curves in the visible sections as much as possible). There is very little straight track and I might end up scrapping the industry at the south end altogether in favor of building something a bit more interesting near the tunnel entrance to staging, now that there is some more space there.

---

Das Eisenbahn"zimmer" in der Garage nimmt Form an. Der Rahmen fuer die Platform ist fertig und eben. Ich benutze dafuer die alten Deckenbalken von Wohn- und Esszimmer. Der Boden ist aus 1.5cm dicken Tischlerplatten, die von kleineren Balken und diversen Holzresten gestuetzt werden. Die ganze Platform ist geschraubt, nicht genagelt, so dass ich das Ganze wieder einfach auseinander nehmen kann, wenn noetig.

Die endgueltige Groesse des Zimmers ist 240 x 255cm. Als ich mir den Plan fuer die Anlage anschaute, wurde mir klar dass ich die ganze Zeit mit 240x220cm gearbeitet habe, und nun ploetzlich 240x40cm extra hatte, was mir erlaubt die ganze Anlage etwas zu dekomprimieren.

Der Schattenbahnhof bekam ein viertes Gleis. Die Rampe zum Schattenbahnhof wurde laenger mit weniger Steigung. Ich habe auch einen fruehen Fehler korrigiert, so dass das Uebergangsgleis von M-Gleis zu K-Gleis an einer passenden Stelle ist.

Der Bahnhof Emsingen ist jetzt nur noch 15 Grad gedreht, was den Gleisverlauf deutlich verbessert. Gleichzeitig verschob ich den Bahnhof etwas nach Norden, so dass ich in der Mitte der Anlage mehr Platz habe. Es hat noch fuer ein weiteres Abstellgleis gereicht. Die ansonsten einwandfreie Gleisgeometrie der Maerklingleise kommt nicht ganz mit der 105 Grad Kurve in der westlichen Bahnhofeinfahrt zurecht. Ich werde das
mit Flexgleis hinkriegen.

Da das Nordende der Anlage nun deutlich tiefer ist, habe ich ein ernsthaftes Zugangsproblem. Ueberall wo man einen versteckten Zugang anlegen kann, liegen unterirdisch Gleise. Ich plane den Bereich um das Bahnhofsgebaeude Emsingen rausnehmbar zu machen, so dass ich ans noerdliche Ende der Anlage komme.

Die Tunnelrampe von Emsingen West entlang der Ostseite hat genau die gleiche Steigung wie die Rampe zum Schattenbahnhof. Ich plane die Schattenbahnhoframpe stabil genug zu bauen, dass ich die Tunnelrampe einfach oben drauf setzen kann.

Ich bin mir nicht so sicher wie ich die Gleis in Talheim anlege. Waere gut die zwei Industrien etwas realistischer anzuschliessen. Ich habe auch eine ganze Menge Tunnel, und wenig gerade Strecken, auf der Anlage, deshalb werde ich versuchen die sichtbaren Bereiche so anzulegen, dass es Spass macht den Zuegen zuzuschauen (weite Kurven soweit das moeglich ist). Ich kann mir vorstellen die Industrie im Sueden komplett zu streichen und stattdessen die andere Industrie in Talheim etwas interessanter auszubauen.

Solar Energy and Congress

Wow, I still don't really understand they way American Laws are made. According to news reports the Senate amended the housing economic stimulus bill with provisions to extend solar tax benefits. Last year they tried a similar thing which in the end was shot down. I wonder, if they changed the solar tax credit to not have a cap, whether I could claim the difference between the $2000 cap from last year and the 30% on this year's tax return. Would be nice, but I doubt I will be able to do this.

Summer is here!

Friday it was 30+ Celsius. Saturday, as the first real day of summer, saw the heat topping out at 32 Celsius, the hot tub filled with warm water, the day spent outside, children playing on the lawn with the garden hose, and solar production going down, since now the cells warm up substantially enough to be outside their optimal operating range.

Last week with blue skies, but a steady cool wind from the Pacific solar production peaked at 24 kWh/day. On hot days like yesterday we average between 20-22 kWh/day depending on temperature and the angle of the sun.

Wie der Schattenbahnhof funktionieren wird

Find the english version here

Nachdem der erste Teil meiner Bestellung von EuroRail Hobbies & More ankam machte ich mir wieder Gedanken ueber die Anlage. Maerklin 2205 Flexgleis und Uhlenbrock 72600 Dekoder waren. I glaube ich werde nicht mehr Flexgleise brauchen. Muss mal rausbekommen, wie man das Gleis kuerzt. Ich freue mich schon drauf Zuege auf weiten Kurven ueber die Anlage fahren zu sehen ... naja, soweit das bei meinen Platzverhaeltnissen moeglich ist.

Die Dekoder sind sehr klein, und passen genau in den Bereich wo derzeit der Richtungsumschalter ist. Ich warte mit dem Digitalisieren der Loks bis die Intellibox eintrifft, so dass ich die Dekoder gleich ordentlich testen kann. In der Zwischenzeit sollte ich mir eine kleiner SPitze fuer den Loetkolben zulegen...

Da der Schattenbahnhof komplett mit M-Gleisen gebaut werden wird, kann ich mir mit den K-Gleisen aber noch Zeit lassen. Dier erste Phase der Anlage wird praktisch nur aus dem Schattenbahnhof bestehen, inklusive der doppelgleisigen Rampe zur mittleren Ebene und einer Kehre am oberen Ende der Rampe.

Ich werde wohl die Weichen im Schattenbahnhof von Anfang an digital betreiben, so das ich die Fahrstrassenunterstuetzung der Intellibox verwenden kann. Hingegen, plane ich die Weichen im sichtbaren Bereich der Anlage analog zu betreiben. Die Anlage ist klein genug, dass man zu zweit schon gut beschaeftigt sein kann, auch wenn der Schattenbahnhof automatisch per Computer betrieben wird. Da die Rampe nun zweigleisig ist, muss ich nicht warten bis ein Zug ganz im Schattenbahnhof angekommen ist, bis ich einen neuen Zug raufholen kann.

So wird das alles funktionieren: All Schattenbahnhofgleise haben einen Zug. Der Computer waehlt ein Gleis, und schickt den Zug auf die Rampe ins Ausfahrtgleis. Bei Bedarf holt man den Zug vom Ausfahrtsgleis und er faehrt in die Anlage.

Die Weichen im Tunnel sind so gestellt, dass es egal ist auf welchem der zwei Gleise ein Zug in den Tunnel faehrt, er kommt so oder so auf dem Einfahrtsgleis des Schattenbahnhofs an. Es wird ein Hilfsmittel/Signal/Anzeige gebraucht, die anzeigt, ob das Einfahrtsgleis frei oder belegt ist. Vielleicht einfach ein Laempchen, eine rot/gruen Anzeige, oder gar ein Vorsignal. Irgendwas das im Kontext Sinn macht, und auf der Anlage ist. Das Einfahrtsgleis beginnt auf der Rampe und muendet in den Schattenbahnhof. Einfahrende Zuege halten auf dem Einfahrtsgleis kurz vor dem Schattenbahnhof an. Von dort uebernimmt der Computer und waehlt ein freies Gleis, in dem der Zug abgestellt wird.

Damit das alles funktioniert brauche ich drei Belegtmelder. Einer am Anfang des Ausfahrtgleises ("Zug bereit den Schattenbahnhof zu verlassen"), einer am Anfang des Einfahrtgleises (stellt Signal auf "Einfahrtgleis belegt, keine weiteren Zuege nach unten bitte"), einer am Ende des Einfahrtgleises ("hey computer, hier ist ein Zug fuer den Schattenbahnhof"). Wenn dieser Belegtmelder wieder frei meldet, kann er das Signal am Anfang des Einfahrtgleises wieder freischalten. Zusaetzlich kann dort zur Sicherheit eine stromlose Stelle sein, um zu verhindern dass Zuege bei der Einfahrt in the Schattenbahnhof kollidieren. Man kann das auch mit 2 Belegtmeldern machen, wuerde dann aber einiges an Sicherheit verlieren.

Jedes Gleis im Schattenbahnhof braucht eine stromlose Stelle am Ende so dass die Zuege wirklich auch vor der Ausfahrtweiche anhalten und Zusatzgeraete wie Rauchgeneratoren abgeschaltet werden. Theoretisch sollten alle Dekoder damit zurechtkommen.

Order Part 1 and how to operate staging

Today, the first part of an order from EuroRail Hobbies & More arrived. Maerklin 2205 Flextrack and the Uhlenbrock 72600 decoders. It's funny to be in California, unpack the box, and read all the German instruction booklets. I think I don't need any additional flextrack, unless it turns out to be cheaper than regular track of the same total length. Will need to figure out how to properly trim the track to length, as well as how track insulation works with K track. I'm looking forward to watching trains on those nice gentle curves through my scenery ... ok, well, mostly gentle curves I don't have a ton of space to play with.

The decoders are quite small and will fit perfectly in the space where the direction changer switch coil of the locomotives is currently located. I'll wait with the actual digitalization of the locos until the shipment with the Intellibox shows up, so that I can actually test the decoder, too. Meanwhile, I need to get a smaller tip for my
solder iron. The solder pads on those decoders are smaller than I expected...

Since the (hidden) lower level of the layout will be built completely from M track, I still have some time to figure out dealing with K track. The first layout build stage will feature the hidden staging yard and associated ramps only. I will probably digitize the switches on that part of the layout right away to make use of the "Fahrstrassen" support in the Intellibox. I am planning to operate switches on the visible part of the layout manually. Aside from maybe having a computer automatically pick through trains from the staging yard and send them on their way, the layout is small enough to easily keep myself (and another operator) busy with manual operation, especially now that the access ramp to staging has double-track and I don't have to wait for a train to make it all the way down to staging before I can send another train up.

Here's how this might work: All staging tracks are loaded with trains. The computer picks a track sends the train to the outbound track on the ramp. Whenever an operator feels like it, they can release the train from the outbound track into the layout.

The switches in the tunnel to staging are aligned so that no matter which track an operator sends a train to staging, it ends up on the inbound track. There needs to be some visual indication to the operator that the inbound track to staging is occupied. Maybe some green/red light? A distance signal? I'd like something that's on the layout and makes sense in the context. Trains on the inbound track to staging stop before the staging yard and automatic operation takes over. Whenever the computer notices a train stopped on the inbound track, it picks an empty staging track, aligns the switches accordingly and the train proceeds under computer control to the assigned staging track.

For this to work, I need 3 occupancy detectors. One at the top end of the outbound track ("there is a train ready to leave staging") , one at the top end of the inbound track (sets signal "inbound track is busy, no more trains to staging please"), one at the bottom of the inbound track ("yo, computer, send this train to a staging track"). Once that detector shows the inbound track free, it can reset the signal at the top to allow another train in. A safety section can be added to make sure no train can proceed into staging if the inbound track is occupied.

I could do this with 2 occupancy detectors, but would loose a little bit safety and feedback to the human operators, since the wouldn't know when the train actually made it safely into the staging yard.

Each staging yard track needs a computer controlled isolated section at the head end, so that trains really stop before entering the exit switch ladder, as well as any accessories (like smoke generators in steam engines) are turned off. In theory, all decoders should be able to deal with this.

A raised planting bed in the garden

As planned I built a raised planting bed right after we came back from Germany. It came out really nice. I used an article from Sunset for the material and general idea. The bed is 8x4ft and a good 1 foot high. I used pressure-treated fir instead of redwood, since it's made for soil contact, and will last longer than redwood. It also was much cheaper. All that's missing now is the planting dirt.

Here are some more pictures

Where do I get 32 cubic feet of bulk dirt in the South Bay? And how do I get all that dirt to my house?

Update:
Home Depot is selling bulk material (rocks, soil, etc.) delivered to your door step, ... errm backyard. Pricing for soil is about 20% of what you pay for packaged soil at the store. The catch? They charge $60 for delivery, so my 32 cubic feet come out to ~$96 delivered, vs. $76 if I get the cheapest soil they have in the store. Nice idea, but I don't need enough that this is worthwhile.

In the end I got only 18 cuft of garden soil, and Patricia picked up some awesome compost at one of the mushroom farms in Morgan Hill for free.

Viva Die Bahn!

As I arrived at Stuttgart Hbf I went straight to "PresseCenter", got a little bit reading material, was minding my own business, not expecting anything bad to happen. My mom drove me to the station, and helped with the luggage.

As I got to the platform, however, they showed those beautiful notices on the destination signs: "Dieser Zug verkehrt heute nicht" This train is not in service today. ... uh ... huh? I have a ticket with reservation for that ICE 576 I even have a seat reservation!

German Bahn helpfully placed a little lady at the platform, "next connection to Mannheim 13:51 from track 9". But I want to go to Frankfurt Airport! "Frankfurt Airport 14:05, change trains in Frankfurt Hbf". Ugh. 2 large suitcases, one carry-on, and my laptop backpack. No way I'm going to change trains.
The information kiosk confirms that the ICE to Mannheim actually continues on to Frankfurt Airport. Good. Now I just need the ticket changed to the other train. Long lines at the "service point", only one guy behind the counter. I go down to the "ReiseCenter", get in another long line... at least it's serviced by 5 counters. 10 minutes later I'm back at the platform, and say Goodbye to my mom.

From talking to other passengers it appears that the tracks were closed. I'm guessing there was an accident, and the tracks were closed for the investigation.

I tried to see if T-Mobile hotspots on ICE actually work ... hmmm. doesn't look like it. I get an IP address, and can talk to the (squid) proxy on the train, but no connection to the outside world. Looks like either there is no connection, or their DNS server is borked.


United Airlines from Frankfurt

After a joyous 70 minutes in the vestibule of an ICE, sitting on top of my suitcase, I arrived at Frankfurt Airport. Frankfurt is hands down the world's worst airport when it comes to signage. It's not that they don't have signs. Actually, there are a lot. However, you need to know how to interpret them. It doesn't help that my United flight is leaving from a part of Hall C that is under re-construction.

Here is my route from the doors of the train to the seat in the waiting room:
- exit train, get luggage cart
- walk around the escalators
- get on long escalator to mezzanine level of the Fernbahnhof
- continue on short escalator to main level of Fernbahnhof [there is a nice glass roof construction here. Reminds me a little bit of the roof at Munich Olympic Stadium.
- enter Fernbahnhof main corridor
- head towards airport, do not stop at Rail&Fly Check-In counters [they are Lufthansa only, boy would *that* be convenient]
- continue through the corridor, avoid other passengers, various small and large booths along the way
- Be puzzled at the end of the corridor: Turn right to Terminal 1, Hall A, or left to Terminal 1, Halls B+C, and Terminal 2.
- Check poster on the wall. Aha! United is in Terminal 1, Hall B.
- Turn left, down the long escalator, cart nose down.
- Watch that carry-on bag! It might slide off the suitcases and hit someone!
- Continue straight ahead, ignore signs to Terminal 2, and continue on short escalator down to the dungeons [I think the reason why they didn't just extend the dungeons to the Fernbahnhof is that there is a large building in the way (parking?) ]
- Watch the really short end of that escalator, climb a few steps backwards on the escalator for more leverage to push the cart over the bump at the bottom of the escalator.
- Make a U-Turn to avoid hitting the wall right after the escalator [Be happy, that you didn't have to take the route in the opposite direction. That escalator was out of order... ]
- Hang left and navigate through cross-traffic of people leaving the airport for the regional train station, towards a rather narrow pair of doors back into the airport. Those folks show no apparent interest for someone trying feverishly to keep his luggage cart on track.
- Get on a long escalator up to Departures in Hall B. Where are the United counters. Good thing I remembered the counter numbers from earlier (501-507). Eventually, I found the United counters in a corner dominated by almost 50 Lufthansa counters.
- Be pleasantly surprised that there is absolutely no line at the United counters. The counter personnel was visibly bored when I arrived. My two suitcases weighted in with a total of 47kg. No complaint from behind the counter. Phew.
- Continue on to Hall C, hang left through a barely marked door into a hallway with a few stores.
- The end of the hallway is fenced off, turn left following signs to C2-26
- Finally, the security check ... uh, wait. All doors are closed? My face must have looked pretty dumb. So the security check is closed. What now?
- Eventually I see more signs to gates C2-26 that lead into departure hall C [huh???] , through the hall into a new hall that was apparently added later and is not in operation yet.
- I turn around head back to the departure hall and get a book and something to drink.
- Walking by finished but empty counters I continue through the new hall, hang right, past closed store fronts with workers still building the stores inside.
- Make a sharp left turn and hang right into a somewhat dimly lit corridor with open ceiling, past construction walls.
- The coolest part was a large tarp hanging under the ceiling with a drain pipe into a waste bin. Apparently water is leaking from the roof into the corridor.
- Continue to the end of that corridor and hang left into another smaller corridor, down a short escalator.
- Finally, the security check for gates C7-9.
- No-one in line, I'm through in no time and find myself a seat near C7.

Boarding starts in 20 minutes. Time to pack away the computer and get in line to the gate area.

It's gone

The big layout of my childhood no longer exists. Here's how things went down...

Tuesday: 2h, most of catenary.

Wednesday: 2h, more catenary, the first sections of track on the upper level.

Thursday: 3h, bridge, most of the upper level, start with freight area.

Friday: 5h, ramps, main station, rest of freight area and remaining visible track.

Saturday: 3h, dismantle mountain to get to the tunnel tracks, remove tunnel tracks;
4h, box all material, and clean out parts from base plywood.

Sunday: 1h, removing cables from the underside of the layout

16 working hours to take this layout apart cleanly, and pack away salvageable pieces. The saying is true, it's much easier to destroy than to build...

Left to do is cleaning out some more of the electrical from the underside of the layout, as well as removing some control switch boxes for a temporary setup back home.

Decoders

In most of the forum posts and descriptions I read, people recommend converting Maerklin's "Allstrom" motors to a regular DC motor (e.g. using Maerklin's "Hochleistungsmotor" conversion kit), or replace the motor altogether, and then use a decoder for the Motorola format (such as Maerklins c90 or c91 decoders) to convert them for digital operation. The conversion kit comes with a decoder and seems to go for ~100 Euros.

While browsing Viessmann's catalog I found a decoder that's made specifically for Maerklin's "Allstrom" motors (Viessmann 5274). The decoder is actually made by Uhlenbrock with part number 72600, is functionally equivalent to Maerklin's c91 decoder, fully programmable using CVs, with speed regulation, and has 4 function outputs. The nice thing about this decoder is that apparently you don't need to do anything to the existing motor. Just replace the direction changer switch/solenoid with the decoder, re-solder a few wires and you're set, provided the loco runs fine mechanically. Sounds too easy to be true. The decoder runs on regular AC, and Maerklin Digital (Motorola format) tracks, and costs around 45 Euros.

I'll see if I can find that decoder around here and try it out with one of the Diesel or Electric locos we have.

And yes, this is a hobby that can get expensive very quickly ... sigh

Update:
Turns out eurorailhobbies.com is selling the 72600 decoder for $47.99. No point trying to get them in Germany. Their pricing on new Marklin K-track is also very competitive compared to German second hand retail, or online retailers in Germany, especially taking into account exchange rates. I see an order in the near future...

Starting to dismantle the old layout

It's strange to take apart something you spent months and years to build, and help to build, many, very many years ago. Last night I dismantled the catenary of the family layout. Next up are a few left-over catenary masts, and the semaphor-style signals. Then we'll move on to vacuuming the dust from the layout and brush off dirt from all tracks, followed by removing all the track. In parallel I'm surveying locos and will pick a few first victims to get a decoder.

In the ideal case this will all be done before I'm packing my suitcase again and I'll take enough material back home to start experimenting with running locos and trains using digital controls. I'm particularly interested in ways to control digital trains using analog signals, since I'm planning to only digitize operating trains, but leave controlling switches and signals manually. I might add computerized control later (particularly in my hidden staging area), but we'll see about that when it's time.

Sunday

It's nice to be in a European city again. There is a working public transit system that people actually use. In the evening there are regular people out on the streets, enjoying themselves while they are trying to decide which restaurant to go to. People walk to work (yes, I know, strange concept). But the thing that hit me the most:

The chime of church bells on Sunday morning. I don't know how to say this, but it makes me happy. The sound of the bells over the background noise of the city... it sounds right.