Full function signal system

Started by DACS, January 14, 2016, 09:03:48 AM

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DACS

Did some more work on my first ever scratch built signal.  I can already see there are some changes I need to make in the construction.
But learning is a rocky road sometimes.  No pain, no gain... :o :o

Not much texting to do.  Just add some pics.













Making the braces for the shield at the moment.  Pretty much out of time today though.  Almost bed time.  2:30 a.m. comes pretty early.
By the way, the model in the background, is a radio control model of a World War II American Destroyer.  Fletcher class to be exact.  She really runs very nicely.

Dave
Seattle
I am never having another birthday.  The candles for the cake are starting to cost too much!

ACL1504

Dave,

Wonderful thread, very informative. I think the signals look great.

Tom ;D
"If we are to guard against ignorance and remain free, it is the responsibility of every American to be informed."
Thomas Jefferson

Tom Langford
telsr1@aol.com

DACS

Thanks Tom!  I am doing my best to keep it simple.  It is a struggle sometimes.

Put the signal on hold for a bit.  It was just to fill in space till I got things going on the signal system again.

Here are pics of the PCB pattern.  Granted, they are extremely oversize, but they can be used to make your own or, to use as a hardwire guide.
That is a lot of work for hardwiring though.  But, if that's all you feel you can do, then by all means, go for it!  I look at making my own PCB's, as just another part of the hobby and I find it very enjoyable.

This pic is just the circuits for the signal board IC.  This is set up for Normal lighting.



You will notice, there is a slash mark below and between pins 7 and 8 of the IC.  This is where the trace would be cut if one was to go with approach lighting.  Later on all that though.

This pic is showing the component and pad connections.

Re.....Red enable.  From the detector board
Rc.....Red cathode.  To the red led in the signal head
Yo.....Yellow out.  To Ye on the previous board.
Ye.....Yellow enable.  From the Yo on the board before.
Yc.....Yellow cathode.  To the yellow led on the signal head.
C......5v common or ground on pwr supply.
Ge....Green enable.  Used only if using approach lighting.
Mt....Mast connection or common anode.
Gc....Green cathode.  To the green led on the signal head.
5v....+5v. connection on pwr supply.



I am preparing pictures and drawings of the interconnections for the signals as well as for the turnouts.

If there are any questions or comments, please feel free to ask or make them.

Dave
Seattle


I am never having another birthday.  The candles for the cake are starting to cost too much!

jbvb

The first breadboard demo you showed seemed to be driving bi-polar (2-lead, 2-color) LEDs.  But your signal uses 3 separate LEDs and the PCB you show today has 3 outputs (I know there are 3-color LEDs with 4 leads).  Do you plan to do anything further with bi-polar LEDs and searchlight signals?
James

DACS

Thanks for the drop in and inquiry James.
The Breadboard shows three led's per head.  The camera made it appear that there was just one.  The brightness of the led colors ran together.  I didn't use a filter.   But, I assure you, it is three color position light.  There are no bi-polar led's in this circuit. 
I suppose, once this system is finished, I could give searchlight signals a go. I just don't think I could really improve or do much different than what others have done.   I have always been a large fan of position light.
A lot has been done, as far as circuitry for searchlight is concerned.  Rob Paisley does a pretty good job of it.  I really like this system, because it is very inexpensive and it uses a minimum of components.

Dave
Seattle
I am never having another birthday.  The candles for the cake are starting to cost too much!

DACS

Little extra note here.  Did a lot of work on the signal today.  Here are some pics of where its at.  Again, this is my first time at building one of these and its all brass construction.











It is being driven by the signal system on the breadboard.
Just 30 more to go!  Once this one is done, the rest should not take as long to build.  This is the prototype of course.
Some with double heads, for crossings.  Some with four aspect for turnout interlocking.  Then many just like this one.

Dave
Seattle
I am never having another birthday.  The candles for the cake are starting to cost too much!

DACS

#36
Perhaps I should have been building this prototype signal in another thread.  But, it does go with the signal system.  So here I go again.
I was not really planning anything today at all.  Quite frankly, I was just going to be a couch potato, but I just could not keep my hands off this signal.

Here are some pics of the upper rails and platform.





Gotta do a little bending here and there and make small adjustments





Getting real close now to final fit.











The handrails are made from 1/64" brass rod.
The deck plate platform, is made from some brass etchings from Toms  modelworks.  They are actually, made for a model ship.
But what the heck, it works.

Well, there it is so far.

Dave
Seattle
I am never having another birthday.  The candles for the cake are starting to cost too much!

S&S RR

Dave


I'm really enjoying the thread.  Thanks for sharing this with us. The signals look great.
John Siekirk
Superior & Seattle Railroad

bparrish

Dave...

This is really cool stuff

thanx
Bob
Did you ever notice how many towns are named after their water towers ! ?

DACS

#39
Thanks John and Bob, for the comments!
The are much appreciated.
When I get this prototype finished, I may do an sbs on construction.

Dave
Seattle
I am never having another birthday.  The candles for the cake are starting to cost too much!

DACS

Apologies for the drawings that were here.
They really were not very clear.  So I am redrawing them and will repost.

Dave
Seattle
I am never having another birthday.  The candles for the cake are starting to cost too much!

DACS

#41
Here are the redrawn connection diagrams for this system.



This is a continuation of the above photo.  Left side of above photo, goes to the right side of this.



I have been asked what detectors I am using.  Detectors, are pretty much your choice.  You can build your own, which is what I do.  I have or am using a detector designed by Rob Paisley. 
Just remember, when there is no train in the block, it does not matter if the detector is powered from rail power or not.  The logic for this system is negative logic.  Low is true and high is false. 
So, the signal system automatically goes low when unoccupied or... signal green.  When the block is occupied, the system goes high or false... or, signal red.  As DCC supplies power to the rails at all times, there is no need for a tickle voltage to run the system through the detector.
Having said all this, I am however, using a detector, that takes its power from the DCC booster system.  There is a voltage drop with this detector of about 2volts, because of the diodes.  It does cause a higher starting voltage of your trains and they will stop before your throttle is all the way off.  This causes no issues for me at all.  If it bothers you, he has a transformer style detector on his site also.

He has many useful circuits here:

http://home.cogeco.ca/~rpaisley4/DccBodXfmr.html



The opto-isolator on the output of the detector, is what runs the signal system.  5v gnd is connected to E.  The output Re, is connected to D.
I have also made the PCB layout for this detector.  Which I will post later.

Dave
Seattle
I am never having another birthday.  The candles for the cake are starting to cost too much!

DACS

Hey y'all

Today, I started working on a turnout interlock signal.  This is a regular signal with a lower, single target and lamp. (LED)
When the turnout is reversed, this lower signal will go yellow, while the upper signal will be green.  When the loco enters the passing siding, the upper signal will go red.
This means that the approach normal signal will be red also.
So, the engineer has an absolute, but proceed with caution be prepared to stop.  The placement of the yellow is always for turnouts only.
He knows he is being put on the siding.

Here is where the lower signal will be placed.  If on the right hand of the mast, it is a righthand turnout.  Left side, left hand turnout.
My railroads choice.



The LED's with their rounded face, does not look like a real lense.  So, I file the top of the LED flat.  IMHO, it looks more realistic.



Here it is with the hood placed, (still needs final filing and fitting). Also the shield.  You will notice that the shield has been flattened on two sides.  I preferred this look over the fully rounded shield.  A matter of my perspective.



I will also be making grade crossing interlocking signals.  These will have taller masts and one upper and one lower three color position light heads.  There are four per grade crossing as per rules.
These show aspect for the crossing block and the next block beyond.  These can show green over green.  Green over yellow.  Yellow over yellow.  Red over red.  Yellow over red.  Red over yellow....hmmm.

Dave
Seattle
I am never having another birthday.  The candles for the cake are starting to cost too much!

jbvb

This probably doesn't apply to all LEDs, but I filed a 'diffused' T-1 LED flat on the front and lost most of the 'diffused' effect - the point of light from the silicon die was much more pronounced and the beam less focused.  How important this is probably varies with situation and layout owner.
James

DACS

Yes, you are right on the filing an LED.
But, it sets them back into the hoods more.  The light that is emitting, works fine for me.  It was not really a recommendation for anyone, just my personal way.

Dave
Seattle
I am never having another birthday.  The candles for the cake are starting to cost too much!

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