Hello all, I decided to take up the challenge here and provide hopefully enough of an idea that then anyone who is actually serious about exploring electro-mechanical point control using just one point motor can actually get on and do something.
Concept is taken from a turntable with indexing to align a point motor with its appropriate wire in tube partner. I have shown 5 but if you really want to do 40 I can see no problem with that either.
Hopefully the plan view sketch (5 seconds work) will make the idea / concept fairly plain to see.
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The LEDs shine up from under the disk and through the hole only when the hole is aligned over the correctly lit LED. This means that when you make Wire in Tube (WIT) target number 2 (press button, DCC, PC, whatever) this sets the motor off rotating the disk until the hole falls over the LED and the light shines through and hits the Light dependant resistor thus cutting the motor drive circuit. This has aligned on the opposite side a point motor of some sorts ( I have shown a coil / solenoid type but if it is only one it could even be a Tortoise and still remain at the GBP40 budget). I trust this makes some sense. Go and build it and report back I say
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The target size and shape can be adjusted for any innacuracies in the LED/LDR combo.
PS, to save even more money you could mount the LDR directly over the hole on the disk saving on LDRs.
Concept is taken from a turntable with indexing to align a point motor with its appropriate wire in tube partner. I have shown 5 but if you really want to do 40 I can see no problem with that either.
Hopefully the plan view sketch (5 seconds work) will make the idea / concept fairly plain to see.
The LEDs shine up from under the disk and through the hole only when the hole is aligned over the correctly lit LED. This means that when you make Wire in Tube (WIT) target number 2 (press button, DCC, PC, whatever) this sets the motor off rotating the disk until the hole falls over the LED and the light shines through and hits the Light dependant resistor thus cutting the motor drive circuit. This has aligned on the opposite side a point motor of some sorts ( I have shown a coil / solenoid type but if it is only one it could even be a Tortoise and still remain at the GBP40 budget). I trust this makes some sense. Go and build it and report back I say
PS, to save even more money you could mount the LDR directly over the hole on the disk saving on LDRs.
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