single push-button points operation - QUESTION

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Deltech
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single push-button points operation - QUESTION

Post by Deltech »

For DCC.

Hello everyone; this is my first post.

In the vein of "each to their own" and "it's your layout", I am not a fan of toggle switches for points operation.

My ideal scenario would be a control panel with push-buttons to operate the points (and LEDs to indicate normal or reversed).

Is it, therefore, possible to operate points from a single-push button (one for each set of points obviously) where a push of the button throws the points one way, and a further push of the same button throws the points the other way?


IF THIS IS POSSIBLE, can this be achieved without using "shop-bought" decoders/modules/controllers et al?

Just power supply/points motor/push-buttons/LEDs/capacitors/diodes/resistors etcetera.

I would:~

a) like to have it (if it can be done);

AND,

b) keep it as inexpensive as possible.

I do not want it to be computer-controlled, and I am open-minded as to what brand/type of points motors to use.
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Flashbang
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Re: single push-button points operation - QUESTION

Post by Flashbang »

Hi
IMO the cheapest is to build electronic control kits as supplied by MERG, under their CBUS range of items. https://www.merg.org.uk/

If you're not up to soldering components onto a PCB, then consider the ready built and tested offerings using similar technology from such as Megapoints https://megapointscontrollers.co.uk/sho ... cba1185463

Servo motors are becoming increasingly popular for slow motion point movement controlled from MERG or other manufacturers control boards! I'm using SG9 Servo motors on MERG mounts to operate all my points on my new layout. See https://www.brian-lambert.co.uk/High-Hopes.html Great slow movement of the points. Panel point position inductions and all via a single PB operation! :D
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Deltech
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Re: single push-button points operation - QUESTION

Post by Deltech »

Hi Flashbang, and thanks for quick reply.

I am very comfortable soldering, and despite "playing" with real Trains for the past 28 years, my original trade was in engineering, with some electronics, so I am happy to solder/wire whatever needs to be done, but being a tight git I simply do not want to buy either ready-made boards, or put-together kit, hence my original question still stands.
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Flashbang
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Re: single push-button points operation - QUESTION

Post by Flashbang »

Hi
No, I don't believe such can be achieved without spending some cash on control circuits! Even the MERG kits are reasonably cheap compared to ready made units! Around 10% to 20% of the ready made cost!
In life, I've found you get Owt for Nowt! :D
If you do, its likely to be rubbish or cost far more to improve it! :o
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Deltech
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Re: single push-button points operation - QUESTION

Post by Deltech »

As I said, IDEALLY it would be without the purchase of "specialist" kit, but if that's not possible then I guess I'll have to spend a bit more, but the main thing is push-button; once for normal; once for reverse.

I'm not a member of MERG, but (assuming YOU are), could you guide me as to what I would require, and the costs?
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Re: single push-button points operation - QUESTION

Post by Suzie »

Yes this is possible.

There are off-the-shelf products that do this, but if you want to make your own I would suggest looking at making a circuit based around a 'D' type latch such as the 4013 IC and using the output to drive what would normally me controlled by a toggle switch. You can probably drive a Tortoise motor directly from the chip outputs when powered from a regulated 9V supply.
Deltech
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Re: single push-button points operation - QUESTION

Post by Deltech »

Hi Suzie.

Thanks for yer input.

Designing electronic circuits is absolutely NOT my strong point.

I am confident/competent to BUILD any circuit; but only from a diagram.

You, clearly have a far better understanding of electronics than me, so could ye either, A) be so kind as to provide a suitable circuit, or B) steer me towards a suitable off-the-shelf product?

Thanks.
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Re: single push-button points operation - QUESTION

Post by Suzie »

The Signalist SC2 will operate servo point motors and switch the frogs, and can be triggered from push buttons.

This is the basis of the 'D' type latch circuit:-
Image

Leave of the 470R resistor and LED, and connect the Tortoise between the Q and Q-BAR outputs, and run the circuit from regulated 9V DC.

IC pinout here, you get two latches in each IC:-
Image
Deltech
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Re: single push-button points operation - QUESTION

Post by Deltech »

Suzie; thanks for the diagram.

Will this circuit provide a short “pulse” output upon pressing the button, OR, a “constant” output?

And is it alternative forward/reverse upon subsequent presses?

Where (in this circuit) do I connect the points motor?


Regards the SC2; although it has 3 “powering” options (DC, DCC, track power), it seems to be DCC “controlled”, so I don’t think it will serve my needs (unless I am missing the point?), as I want the points to be “operated” by push-button.
Suzie
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Re: single push-button points operation - QUESTION

Post by Suzie »

The 'D' latch circuit provides a constant output that will be suitable for a Tortoise point motor.

Each time you press the button the point will move to the other position and stay there.

The Tortoise point motor (and only a tortoise will do, most of the others of similar type draw too much current) connects between the 'Q' output and the 'Q-BAR' output (sorry I cannot produce the correct Q-BAR symbol on my keyboard - it is the output that is wired to the 'D' input).

The SC2 is primarily a DCC decoder for driving servo point motors, but it has a local panel input option where you can wire some pushbuttons too so that it can be controlled locally. You can either use two buttons, or a single 'toggle' button.
abenn
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Re: single push-button points operation - QUESTION

Post by abenn »

For the past couple of years I've been using home-made circuits using PICAXE 08M2 programmable integrated circuits to activate point servos, switch the frogs, and provide LED indication on the panel. I use them with switches but, being programmable, they could also be configured to use a momentary pushbutton and any kind of point motor you want.

Using a PICAXE 16M2 I have a unit that controls the two servos used in a single slip, plus the frog and LED switching. The PICAXE units are designed for use in schools, and have good online documentation and a downloadable programmer, which uses a quite simple programming language. Each chip is more expensive (£2.26 for the 08M2) than the flip-flops mentioned by Suzie, but are worth looking at because of their flexibility.
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Flashbang
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Re: single push-button points operation - QUESTION

Post by Flashbang »

Hi
I feel despite all the excellent answers in posts and suggestions provided so far, until you specify a couple of things we are running around in ever decreasing circles making suggestions :o

What you should advise on now is a type of point motor to be used. Solenoid, Stall/slow motion, Servo or Stepper motor. I appreciate you have said ..
I do not want it to be computer-controlled, and I am open-minded as to what brand/type of points motors to use.
Not knowing what to offer/suggest is almost impossible as Servo motors operate differently to a Stall motor and Solenoid motors require beefier power supplies and controls.

Next, you have posted in the DCC forum section. Are we to assume you want DCC control or will analogue be better for you? Cost of DCC control is always going to be far, far more than Analogue.
IF THIS IS POSSIBLE, can this be achieved without using "shop-bought" decoders/modules/controllers et al?
Just power supply/points motor/push-buttons/LEDs/capacitors/diodes/resistors etcetera.
We await your final decision and can then probably help you further. :)

You asked what the cost of MERG Servo control was .... Of course you have to join MERG, but omitting that cost as its for everything MERG offers included help and guidance via their forum, then the below is what I paid for Servo control in January this year...
Servo costs.jpg
You can go beyond this and have CBUS control from the control panel Push buttons to operate everything around the layout by two wires It can operate Solenoids, Stall motors or Servo motors as PCB and components are available for all types, it can bring back panel indications from each item if desired to the panel, all on the same two wires, but then the cost of course increases. But IMO it is still far cheaper than DCC :D
Servo costs-2.jpg
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Deltech
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Re: single push-button points operation - QUESTION

Post by Deltech »

Flashbang et al:~

The Trains will be DCC operated. My son started with a Hornby DCC Virgin Pendolino set from about 6 or 7 years ago, and has bought some extra stock (also DCC) and track over the years, and has a lot more track than what is shown on the Horny trackmat, and it is now time to "partly modernise" things by changing to motorised points.

It would seem logical to continue with DCC for the stock, plus he wants sound next (so do I..........).

Whereas the "slow acting" points motors look great, we cannot justify the extra costs so will be going solenoid, but haven't made a final decision on brand, but would want to control frog polarity, LEDs on control panel to indicate route, (and possibly signals).

I use the term "partially modernise" because neither of us want a laptop/iPad to be in charge of things. There is still nothing to beat controlling the Trains oneself; likewise operating the points by switches/levers/buttons, but NOT "computerly" (Is that a word? It is now).



Back to the "single-push-button" thing......

I have found a circuit, on which I presume is an American site, given the use of the terms "turnout" and "switch machine motor", and I (have hopefully managed to) attach the circuit below (it may require some alteration as it only shows 2 wires to the motor, so I "presume" I could fit these to the "normal" and "reverse" contacts, and only one or the other of them will have a voltage with respect to ground at any one time?).

Now, whereas my understanding of electronics is basic-at-best, and I don't pretend to understand how the designer of this circuit could just come up with such a thing in his (or her) head, I am very much capable of building this, and integrating it into a layout (if it is suitable, of course).

And it would cost pennies!!!!!!!!

BUT>>>>>> can those of you with a better understanding of electronics please comment on whether this is suitable for my OP?

For example, would this circuit provide a "pulse" or constant voltage on the output side?

If it is constant, what can I do to make it "pulse"?

Or, if this particular circuit cannot be altered to provide a "pulse" to the points motor, is there any alterations that can be made to make the voltage at the points motor "bleed off" once the solenoid has "activated"?

And finally, whether there would be any issues using this with any of the major brands of solenoids?



Thanks again.
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Flashbang
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Re: single push-button points operation - QUESTION

Post by Flashbang »

The circuit you have provided drives a small electric motor one way then reverses it when the PB is depressed again.
Current through the IC is low say no more than probably 200milliamps (0.2A) maximum - Just guessing.
Solenoid point motors draw around 3 to 4 Amps (3000 to 4000milliamps) in a brief pulse. Anything that high powered needs something beyond the output of an IC. Such as a MOSFET which has a maximum power rating of 30Amps so can easily withstand the current rush needed for a solenoid coil Two MOSFETs are used per point motor (One for Normal the other for Reverse directions)

Unfortunately, you are not going to get anything cheap! In fact if it were myself wanting simple control panel point operation and possibly LED point position indications then...
I would obtain the following and wire for conventional solenoid point analogue operation...

Power supply Ideally a dedicated power source such as the Gaugemaster WM1 https://www.gaugemasterretail.com/magen ... c-wm1.html Note; Frequently cheaper from other GM stockists, or use the 16v auxiliary output from an old train controller.
A CDU - eBay offers a good selection from around £6 up https://www.ebay.co.uk/sch/i.html?_from ... &_odkw=cdu
Press to make momentary Push buttons (2 per point - one in each direction) https://www.ebay.co.uk/itm/2K118-10-x-B ... 4&LH_BIN=1
Wire which ideally should be 16/0.2mm equipment wire in three insulation colours.. https://www.ebay.co.uk/itm/Model-Railwa ... 932f4fa424

Seep PM1 motors which include a single change over switch for indication/signal illumination.


For indications you would need a suitable power supply 5 or more typically 12 volts DC at about 1.0Amp or a little higher. https://www.ebay.co.uk/itm/12V-2A-UK-PO ... SwVupTrWfS
LEDs of choice but try to get voltage rated one which have a resistors built in https://www.ebay.co.uk/itm/3-5-10MM-GRA ... Sw-RRXCXnW
Wire in 7/0.2mm https://www.ebay.co.uk/itm/Model-Railwa ... 932f0bf3d5

Note all the above links are suggestions just to give you the idea. :D
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Deltech
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Re: single push-button points operation - QUESTION

Post by Deltech »

Flashbang, I respectfully doff to your superior knowledge, and I gratefully acknowledge the parts list you provided for a two-buttons-per-points system. I think I could comfortably "throw that together".

I am also very grateful to the other contributors; especially when I as a relative newbie have nothing to offer anyone else in the forum.


Ok, new angleon OP....

Ok; I accept there's no "cheap" option for me to achieve what I want, so I will just have to accept that I will have to buy off-the-shelf stuff to achieve my aim of a single-button operation of points.

BUT>>>> in addition to the parts list you provided, what do I need to buy for single-button operation? There surely must be an off-the-shelf "module" that will do it?

And we'll stick with solenoid motors.

Forgive me if I am either not grasping things ye have said, but my son and I have only ever set points "with our hands", so have no prior experience with points motors, additional power supplies, etc.

None of the above phases me (little AC joke there), and from the information gleaned in this and many other posts on this forum, plus YouTube videos, I am confident that I could construct a two-button system without any trouble at all.

But can it yet be done by single-button, and I'll just let a few moths out of my wallet.
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