Paddy Mac Namara

i like this little layout, my advice keep it simple for your first layout, also i'm shocked you left the mechanical engineering brotherhood to go to the dark arts of software.

i'm not a great fan of the "emoji" likes, so here's some real words. "i like". track plans etc...?????

got a new loco for the layout, the scale maybe a bit of but it's dcc

Thanks Dhu, could you share some detail on this detection circuit, photos, circuit diagram, list of parts? cheers paddy mac

hi sven, thanks for your comments and interest. I don't think that will be a problem, my previous experiments, see vid from 10th march 2019, show that the magnet does engage reed switch when attached to loco, in fact the magnet is very close to the switch as it passes over. What i was more concerned with is the double contact of reed switch as the magnet passes over it as shown in the video below. When using the Arduino and coding this was a problem and that is why there is a time delay in the code, so that the code ignores the second contact. With this circuit as long as the magnet passes over the reed switch reasonably quickly, the charging and discharging of the capacitor takes time so the second contact does not cause a problem. According to this site it takes 0.25 sec to full charge.https://www.allaboutcircuits.com/tools/capacitor-Charge-and-time-constant-calculator/

As shown above the circuit using the Arduino allows for control of the junction with a loco going both ways. In my post of 10th march 2019 i could only get control in one direction using relays only and i have been trying to solve this for a year...Despite my best efforts i could not devise my own solution, however i came across the solution below recently and it is very satisfactory. more detail on how the circuit works: The initial state for this circuit is relay in Reset State. Thus the relay armatures are connected to cm-nc. The led is lit up, the led represents power to track you wish to isolate. Capacitor C2 charges up to +9V via 2.2k resistor R2 while capacitor C1 remains discharged as it is not connected to the 9V supply. If reed switch R1 or R2 is activated,C2 discharges via the relay’s “set” coil 2 and diode D2.This switches the relay into its set position, thus relay armature are connected to cm-no, the LED will switch off. C1 then begins to charge via R1. While R1 or R2 are activated the relay does not return to the reset position because the current supplied via R1 is insufficient for the coil to latch the armature. Once the relay has switched and C1 has finished charging, activating R1 or R2 again causes the relay to switch back to the reset state via coil 1 and the LED comes on again. The relay is a two coil 5v latching relay: Hongfa HFD2 005 M L2 D Bi-stable Latching Relay DPDT 5v, 2 coil, 2A. Purchased on ebay around €2.50/3.00 Capacitors are : Rubycon Electrolytic Capacitor, Miniature, 22 µF, 25 V, ZLG Series, ± 20%, Radial Leaded, 5 mm. These were purchased from Farnell and cost 10cent each Diodes I had in my electronics box, these only cost a few cent. Resistors I got an assortment pack on ebay of 300 with a range of different resistance values, cost was €5. The website I found this circuit on is: https://www.eeweb.com/extreme-circuits/momentary-switch-teamed-with-latching-relay

doing some scenic work

circuit diagram for above

This is how i would do two track control. But then I have three tracks.....so it's getting a bit messy.

an improvement to the operation with reed switches my electronics workshop

I've posted a couple of vids over on electronics forum showing use of reed switch with arduino, yep i know you can get IR sensors that you can literally just plug and play with, i am going to do some experiments with these too....

As you can see not the most reliable, i think if i change the orientation of the reed switch, lenghtwise it should work better, see photo below of smaller magnet attached to loco here's the ciruit diagram, very scruffy sorry i normally do them on graph paper... Reed switch with arduino.pdf and finally here is code for the arduino, i take no credit for it, i found it after a lot and i mean a lot iof searching, its simple and i like it for that bool junctionclear; void setup() { pinMode(2, OUTPUT); pinMode(9, INPUT); pinMode(10, INPUT); pinMode(11, INPUT); junctionclear = true; digitalWrite(2, LOW); } void loop() { if (digitalRead(9) == HIGH || digitalRead(11) == HIGH) {junctionclear = !junctionclear;} delay(1000); if (junctionclear) {digitalWrite(2, LOW);} else {digitalWrite(2, HIGH);} }

As promised i eventually got around to doing the above with an Arduino, you still need a single coil non latching relay, but it will work both ways, but it is not without its problems. sorry about the sound quality on that one, and me mumbling at the end, here's another one.

Hi Sven funny you should ask that as i am currently working on it at the moment, i switched to reed switches cos they are easier to use and less complicated than IR sensors (transisitors and all that) however they do give two pulses of current per magnet pass, and that is why i used latching relays. I am also working on a solution using arduino, i expect to do a more detailed post over on the DCC electrics and electronics forum over the next few weeks. I work on the electronic stuff in fits and starts, when i'm in the mood. I can still run trains and use on/off button so its not a priority. I'm really just playing around to be honest. I am currently uploading a couple of videos to my Youtube channel, Patrick Mac Namara, there is also a video where i am trying out the Heathcote diamond protector.

looking good nick, welcome to the forum, is that brooklyn bridge in your profile photo? paddy mac

Was doing some rewiring in the lifting flap area and decided to make a virtue of necessity, so i've installed button switches so i can isolate the track on the flap. This area was always going to be semi-scenic and to act as a kind-of fiddle yard, so this w ill alllow me to hold locos in this area while doing other loco movements in the station area.

Being doing some work on the back corner before photos and after

Hi want to model a scene with truck containers, i can download card kits of the containers, but i want to get a truck to put them on and also a rail bogie that would be suitable. I only have space to accomodate the smaller 20 ft containers. any ideas where i could source truck and bogies thanks paddy mac

Hi there, had some repairs done to gas oven and this tubing was replaced, thought it might of use for some detail on layout maybe piping or something. I work in town so could meet up to pass on. Its about 3mm diameter paddy mac

a stunning bit of work, "we're not worthy"

more detail on circuits etc just posted on electronics forum

Just a bit of detail on the video posted on “Celbridge” thread. Here is a photo of the track showing the position of the reed switches and a photo of the circuit board. The reed switches are triggered by a magnet underneath the loco. The circuit diagram is shown below, at top of diagram, a schematic of the track with sensors and a diagram of how the pin contacts on the relays work Relay K1 has power to the track connected thru contacts NC (normally closed) and CM (common). The default for the relay is called the “reset” condition. Thus current flows thru NC-CM. So the Branchline (BL) has power “on”. If loco on ML triggers reed switch R1 current flows thru coil 1 of relay K1 and “sets” the relay, this will then switch the contacts from NC-CM to NO-CM so BL is now power “off”. (NO is the normally open contact on the relay). When the loco on ML triggers R2 current flows thru coil 2 of relay K1 and “resets” it back to default, so BL has power “on” Relay K2 operates in the same way and switches power on/off to Mainline (ML). The circuit operates on a first come first served basis, whichever loco reaches the junction first switches off power to the other loco. At the moment the circuit can only work in one direction, I think I can get it to work “both ways”, but I’m having some difficulty at the moment When and if, I ever get around to actually wiring this up on the layout, I will be switching power on/off on isolated sections, so I won’t have locos suddenly stopping dead on the tracks far away from the diamond junction. This project is still evolving and I’m in no major hurry as I have control of the diamond crossing with simple on off buttons. I have two tracks going across the junction, so double the wiring. I have done some coding with Arduino microcontroller and reed switches with some success, but it’s debatable if using software will simplify things as I still need relays to switch on/off current. For those of you unfamiliar with Arduino, it is, I suppose a hobby version of a PLC (used in more industrial applications), very cheap about €30 , very popular for student projects and hobbyists

I got the card at work, Bolton st college, we have printing department. So its not commercially available. Try Evans art supplies in town for mounting board or something similar.

have a look at the last post on this thread it might help to explain a bit, i will be posting more detail on same forum later

I’ve done a bit more work on my diamond crossing protector again using reed switches but I am using two latching relays this time, it operates on a first come first served basis, you can see what I’ve done in the video below. I’ll put more detail with circuit diagrams etc on the electrics and electronics forum for those who may be interested.