End to End test

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Card tram test end to end line

From a babani book on the 555 timer chip I put together a simple circuit on a bread board. First time I have tried anything like this. Using some HD 3 rail track I set a test length up in the garage and this is the video of it working!!

https://youtu.be/XNiOxaKkvfI

Basically the time interval is longer than the journey time. At each end one track, in this case the centre track, is cut and a diode inserted. When the train crosses the break it stops until the polarity is reversed. The time operated a dpdt relay as the reversing switch.

I now intend trying to build the circuit onto veroboard for a more permanent controller.



freelance model railways and tramways
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Nice job, It's always a boost to the old moral when you get something like that to work
cheers
Marty

Marty
N Gauge, GWR West Wales
Newcastle Emlyn Layout.
Newcastle Emlyn Station is "Under construction"
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Nice work. It is always satisfying to get a circuit working as you intended.  My problem is that when one works I start looking for ways to improve and add to it. For me, it can take over from modelling.

Regards,

Brian

ECoS, Laptop, TrainController Gold v8
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Know what you mean. Being clever I went and made a veroboard version, which does not work. probably my dodgy soldering but I cannot find the problem. Trouble is I soldered the chip straight in not having any sockets.

So off to Maplins for a decent stock of resistors and capicitors plus a few DIL sockets. So back to the prototype board using the relay from the previous exercise. It was not the fault.

With a selection of resistors discovered that the value from the book produces a cycle nearer 7 seconds rather than the 11 the book reckons. Anyhow a bigger resistor now means a cycle time of 14 seconds which is just fine for a test length.

So before I have another go at a soldered unit I am working out the best way to adjust the time cycle by switching in various resistors!

Also rebuilt the chassis with the collector for the third rail in the centre of a bogie. This works although it means rail collection from one bogie and centre from another. Centre collector really needs duplicating. At least I am geting there. This solution was deceptively simple.

First picture is tidied up chassis with centre collector in the centre of a bogie.



Side view of bogie. Collector is just a tube with the Spanish paper holder down the centre. It is held in place by a couple of small self tapping screws through pre-existing holes on either side. Bit of spring on top helps keep it connected to the track when metal support frame is added for necessary traction.



The lastest bread board using the relay cut off my failed veroboard exercise.




Of course, all this is going on because of the lousy weather. I would not have bothered if the weather was better.

David

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