Off to Milton Keynes, home of the Holy Grail, for a big exhibition that I have nothing to do with. Perfect for my boss and I to wander around layout spotting and project purchasing.
There were some very nice layouts on show. No space fillers at all. Dan Everson had the toughest job. His O gauge layout is lovely, but shuttling a single car DMU back and forth is no fun for a weekend. That's the problem with DCC - God's own 12V DC allows you to use a shuttle unit so you get to go for lunch...
One of my favourites was the S gauge American model that flew in from the States, as hand luggage apparently!
Back on British prototypes, High Wycombe junior section has produced a lovely model.
I can't resist a canal, or in this case waterway. Nice dreadger and Bantam tugboat.
We got to see progress on Ellis Clarke's Pug in 4 and 7mm scale.
Hornby's TT:120 signals, which will have working lights.
As ever, being famous, random people wander up and demand a selfie. Obviously, I am generous enough to accede to their request, even if the shutter is pressed when I'm not smiling properly!
I enjoyed the show, although it was a little light on project materials. More box-shofting than modelmaking, but that's very much the hobby now. And of course, I was there on the Sunday, so the locusts had been in the day before.
One issue - no cake. I must remember to take my own next year.
1 comment:
Interesting point about shuttles - and DC v DCC - but it might be a bit more nuanced than you think.
DC shuttles often rely on relays (to switch the polarity of a controller output going to the track. You 'll probably find some carefully positioned track breaks and diodes - to get trains to stop at the end of a track and wait for the polarity to change. There might even be extra breaks and diodes introduced, so trains don't stop sharply from full power and start in the other direction, again at full power.
DCC shuttles exist - I've encountered one on a MERG show demo layout. Please don't ask me how they work - but this layout includes an end-to-end - 2 "chipped" DMUs shuttling back and forth - 2 tracks at one end - 1 track at the other - with a servo-operated automatic point about half way along.
In another part of the demo, 2 diesel locomotives run around an oval - split into sections - automatically starting and stopping, based on whether another train is in a given section.
This relies on using a current transformer to detect a varying current flowing through a track section - and then triggering some electronics.
Lots of people imagine that transformers give outputs in proportion to the input voltage - but then get stumped the moment they connect the input to smooth DC and get nothing out.
This is because transformers actually work in a different way. A changing current in the input coil causes a changing magnetic field - which then causes a changing output. Think of it along the lines of the output being related to the change in the input.
Current transformers often have a wire (carrying the current being measured) wound a couple of times around a ferrite ring - a separate coil of wire is also wrapped round this ferrite ring - and is connected to a circuit which does something with the changing output.
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