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Simple IRDOT-1 Question

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Posted by wolfman hal on Tuesday, May 12, 2020 12:28 PM

That is why I asked if anyone is using thr JTD873GR.  I want to know where they are connection the Anodes an if there is a way I can seperate them. The drawing of the wite harness looks like it could be between the LED in the ends of the wires.

Harold

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Posted by rrinker on Tuesday, May 12, 2020 8:11 AM

 Unfortunately they are exactly backwards for what the IRDOT wants. The IRDOT diagram shows the LEDs with both cathodes to pin 6, and the individual anodes to 2 and 5. You need a common cathode signal.

                                        --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by wolfman hal on Monday, May 11, 2020 3:00 PM

I was seeing the same thing. I wonder if they tied these internally.  Is anyone reading this post  using a JTD873GR?  If so please join the conversation.

Harold

 

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Posted by gregc on Monday, May 11, 2020 2:42 PM

wolfman hal
Am  going to able to make it work with the IRDOT-1 in the first post and what would be the connections 1-6

from https://heathcote-electronics.co.uk/irdot1.html

Wiring

This is as detailed below, but full instructions are supplied with the IRDOT-1.

Terminal 1 Connects to the positive terminal of the power supply

Terminal 2 Electronic switch (open collector transistor) for connection to our other units such as SA8.

Terminal 3 11 volts output used for relays and undetected LEDs

Terminal 4 Not used

Terminal 5 Connects to the long leg of the LED

Terminal 6 Connects to the negative power supply and short leg of LED

 

from above, the IRDOT-1 circuit has a built in resistor for the Red LED.  you would need a direct connection to the anode of the Red LED.

And while a resistor needs to be in series with the Anode of the Green LED, connected to pin 3, you also need direct access to the Green anode to connect to pin 2.

the cathode of both LEDs would be connected to pin 6 which is simply ground.

unfortunately, the wiring shown ties the anodes of both LEDs together and to a common series resistor.   Can't see how the wiring reaches the LEDs. Perhaps you can disconnect it from the LEDs

greg - Philadelphia & Reading / Reading

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Posted by wolfman hal on Monday, May 11, 2020 2:22 PM

I am only going to use a 2 color system.  Am  going to able to make it work with the IRDOT-1 in the first post and what would be the connections 1-6

 

Harold

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Posted by RR_Mel on Monday, May 11, 2020 12:19 PM

By putting two resistor in series with the cathodes and not using the resistor in series with the anode by putting the green and red together you might come up with a three color signal.  I did that for many years.  The newer three lead LEDs have hot spots of red and green in the yellow.
 
Positive to the anode.
 
 
Mel
 
 
 
My Model Railroad   
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
 
 
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Posted by wolfman hal on Monday, May 11, 2020 11:02 AM

[quote user="wolfman hal"]

Thanks for the drawing they really are good. OK Now for another question. While looking for LED's online ( Not Bulbs) I came across Mod # JTD873GR signal.  These will look good in the back part of the layout. 

Here is my question. Hopefulling the image will show but if not here is the question.

It shows Red lead to Cathode  Green lead to Cathode and a black lead with Resistor as common anode. Looking at the first post wiring diagram will this work and is please note the connections.

  

 

 

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Posted by wolfman hal on Monday, May 11, 2020 11:00 AM

Thanks for the drawing they really are good. OK Now for another question. While looking for LED's online ( Not Bulbs) I came across Mod # JTD873GR signal.  These will look good in the back part of the layout. 

Here is my question. Hopefulling the image will show but if not here is the question.

It shows Red lead to Cathode  Green lead to Cathode and a black lead with Resistor as common anode. Looking at the first post wiring diagram will this work and is please note the connections.

  

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Posted by wolfman hal on Monday, May 11, 2020 10:27 AM

See if this works

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Posted by hon30critter on Monday, May 11, 2020 10:13 AM

Thanks Greg,

I didn't know what he was doing wrong.

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by gregc on Monday, May 11, 2020 9:28 AM

wolfman hal

Ok I am trying IMGUR.  I have taken an image of the two types of signals. The one still will be detailed.

Harold

your copying the web page which includes a photo.   On that page you need to put the mouse over the photo and right click (chrome) and "copy image address"  (e.g. https://i.imgur.com/E8RNQPb.jpg). 

on this forum, when inserting/edit image, enter the the image address with a .jpg, .png, .gif suffix

 

greg - Philadelphia & Reading / Reading

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Posted by hon30critter on Monday, May 11, 2020 9:21 AM

Hi Harold,

Your images are not showing in your post. All we are getting are icons which link back to your photos. I don't know what you are doing wrong, but please refer back to my photo posting instructions in order to get the actual pictures to show in your post.

Cheers,

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by wolfman hal on Monday, May 11, 2020 8:38 AM

Ok I am trying IMGUR.  I have taken an image of the two types of signals. The one still will be detailed.

Harold

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Posted by hon30critter on Monday, May 11, 2020 12:31 AM

Harold,

If you are building searchlight signals you might find this helpful:

Credit to gmpullman (ED) for the image.

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by hon30critter on Sunday, May 10, 2020 9:49 PM

wolfman hal
I have the circuit made on my bench and it works fine.  My question is how do you handle the ancote/ cachode to go into the mast? I assume the two must also be insulated from one another.

If you are using 3 mm LEDs then you have to attach smaller wires to the anode and cathode. In my previous post I showed a link to a source for smaller wire. Obviously, the leads have to be kept separate.

If you are only using single colour LEDs then you can solder one lead to the mast and then you only need to feed one wire down the mast for each LED. Make sure you are soldering the same lead (i.e. anode or cathode) to the mast for multiple LEDs.

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by hon30critter on Sunday, May 10, 2020 9:39 PM

wolfman hal
What I need to know is how you handle the Anode and Cathode leeds coming from the LED's with no wires attached? The pictures with wires attatched I have seen have bulkey connections. Are there 3mm LED's Red & Green with small wires attached?  The ones I saw would not fit down the mast.

Hi again Harold,

As you have already concluded, the 3 mm LEDs (please stop referring to them as 'bulbs' - that only confuses the issue) with the leads attached won't work. That means that you have to attach your own leads. Do you have a soldering iron, and if so, what kind?

The wires that you solder to the LEDs can be very fine because the LEDs draw very little power. You can use 38 ga. 'magnet wire' or # 30 ga. insulated wire like this:

https://www.ngineering.com/accessories.htm

If you choose the #30 ga. wire you should invest in a specialized small gauge wire stripper like this because the teflon insulation is a challenge to remove:

https://www.digikey.ca/product-detail/en/jonard-tools/ST-450/K545-ND/1990301

To strip the magnet wire, just put a small blob of solder on the tip of your iron and draw the wire through it.

Dave

 

 

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by hon30critter on Sunday, May 10, 2020 9:23 PM

wolfman hal
I can't tell from the pic but are theses LED's round fronts for the signals. What model # is correct?

The LEDs in the signal I showed are 3 mm bi-colour with two leads. These are the LEDs:

https://www.ebay.ca/itm/100PCS-2pins-F3-3mm-Dual-Bi-Color-Polar-Changing-Red-Green-Led-Diffused-Leds/291991445367?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

Two leads are fine if you only want red/green signals. If you want red/yellow/green signals then a three lead 3 mm LED will work but the yellow indication colour may not very 'true'. If you want red/yellow/green indications with strong colours then the LEDs that Mel recommended are your best bet:

 

wolfman hal
2. These signals are Brass. You mentioned that I could use three wires. Could you draw me a diagram?

You don't really need a diagram. If you have four wires coming from two LEDs and you can't fit four wires inside the mast, then just solder one of the wires to the top of the mast and solder another wire to the bottom of the mast. That still gives you four connections but only three wires inside the mast.

wolfman hal
How do you get the photos on your post?

First, you need to chose a photo hosting site like Imgur and transfer the photos that you want to post to that site. There are several sites that offer free photo hosting but I have found Imgur to be the most reliable.

https://imgur.com/

First, start your post and write the text until you get to the point where you want to insert your photograph. Next, you need to transfer your photos to the hosting site. Open a new browsing window and go to your photo hosting site. In Imgur, once you have signed in, click on your user name and then click on 'Images'. That will open a window with the option to 'Browse' Click on that and you will be taken to your computer's files. Find the photo you want and double click on it.

If the Gods are happy, the Imgur screen should re-appear and your photo should show up in a few seconds as a thumbnail picture. Click on the thumbnail to enlarge it, and to the right of the picture you will see several options. Click on 'Copy' beside the 'Direct Link' option.

Next, go back to your post and put the cursor where you want the photo to appear. In the toolbars across the top of the post you will see an icon that looks like mountains with the sun above. Click on that. A window will appear. Place your cursor in the top box and left click. Select 'Paste'. Then click 'OK'. Your photo should appear in your post.

Sounds complicated, but once you have done it a couple of times it's easy.

I'm going to answer more of your questions in another post.

Dave

 

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by RR_Mel on Sunday, May 10, 2020 2:47 PM

I use #36 Litz wire and run both anode and cathode down the mast tube.  I don’t like having the brass mast “hot”.  I do like Dave’s IC socket idea for mounting!!
 
I used a built up styrene tubing base for my signals.  I slipped several Styrene tubes together to enlarge the signal base to 7/16” so the micro connectors would easily fit through the mounting tube as shown in my earlier post.
 
If down the road you change the drive circuit to the signals and need to reverse the polarity to the LEDs having both anode and cathode on separate wires is a great help.
 
 
Mel
 
 
 
My Model Railroad   
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
 
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Posted by BigDaddy on Sunday, May 10, 2020 2:11 PM

wolfman hal
PS I am trying to see if this posted https://photos.shutterfly.com/full/85102222943

We can't see anything.

A friend of mine is an orthopedic surgeon.  He says the definition of an orthopedic surgeon is someone who does an operation, that he has never done before, and the first time he does it, he modifies it.

And doesn't know he's modified it.

You have modified this part of the instructions:

Whatever hosting site you use, make sure your settings allow your photo to be viewed by anyone, or all you'll get is a broken-image icon. The Model Railroader User Gallery won't work, because it requires you to be logged in. Any site that requires a login won't work, even if visibility is set to Public. That includes Facebook, Twitter, Instagram, and the like.

 

Henry

COB Potomac & Northern

Shenandoah Valley

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Posted by wolfman hal on Sunday, May 10, 2020 9:47 AM

I have the circuit made on my bench and it works fine.  My question is how do you handle the ancote/ cachode to go into the mast? I assume the two must also be insulated from one another.

Harold

PS I am trying to see if this posted

https://photos.shutterfly.com/full/85102222943

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Posted by BigDaddy on Sunday, May 10, 2020 9:45 AM

What I need to know is how you handle the Anode and Cathode leeds coming from the LED's with no wires attached?

Look at how they are attached in the pictures of this ebay signal

Posting pictures, you have to follow the instructions in the sticky post.  Forget anything you think you knew about posting pictures anywhere else.

Henry

COB Potomac & Northern

Shenandoah Valley

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Posted by gregc on Sunday, May 10, 2020 9:35 AM

wolfman hal
4. What I need to know is how you handle the Anode and Cathode leeds coming from the LED's with no wires attached? The pictures with wires attatched I have seen have bulkey connections. Are there 3mm LED's Red & Green with small wires attached?  The ones I saw would not fit down the mast.

i would solder wires to the LED and then with a 1k resistor connected to the the + terminal of 5V, touch one LED wire to the resistor and the other to ground.  It will only light when connected properly.   Solder the resistor to mark either anode or cathode or tie a know in one of the wires.

wolfman hal
5. Also.  How are you getting pictures posted on this site.  I could probably do a lot better with pics.

see 1st link, "How to Post a Photo on the Forum" on the General Discussions Forum page

greg - Philadelphia & Reading / Reading

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Posted by wolfman hal on Sunday, May 10, 2020 8:52 AM

Ok 

Let me clarify A few things

1. I am modeling in HO Scale.

2. I am going to be using the IRDOT - 1 with the curcuit described in the first post.  I have tested it and it works perfectly and I have several of them.

3. I did not know the size of the 603 and will be using the 3 mm bulbs. Several of the masts have 2 Seperate heads so I want to use seperate Red and Green Bulbs

4. What I need to know is how you handle the Anode and Cathode leeds coming from the LED's with no wires attached? The pictures with wires attatched I have seen have bulkey connections. Are there 3mm LED's Red & Green with small wires attached?  The ones I saw would not fit down the mast.

5. Also.  How are you getting pictures posted on this site.  I could probably do a lot better with pics.

 

Harold

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Posted by RR_Mel on Saturday, May 9, 2020 11:25 AM

Harold
 
I don’t see the scale you are working with, you haven’t mentioned scale or size of your signals, only 3mm GOWs.  I model HO and a standard 3mm LED is = 10¼” in diameter, perfect for an HO signal.  Just wondering why you would using the tiny 0603 LEDs.
 
 
I use three color signal heads with a tri-color LED.  If you only want two color heads you could go with a 3mm bi-color LED with either two or three pins, series or individual drive.
 
 
The signals above are HO scale with 3mm 3 color LEDs, the signals are scratch built to scale.
 
This is a SMTL-4RGY three color LED.
 
 
 
It is about twice the physical size of the 0603 but has three colors.  Much easier to work with compared to the 0603.
 
 
 
 
 
Mel
 
 
 
My Model Railroad   
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
 
 
 
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Posted by wolfman hal on Saturday, May 9, 2020 10:29 AM

Ok Dave 

A couple of new questions

1. I can't tell from the pic but are theses LED's round fronts for the signals. What model # is correct?

2. These signals are Brass. You mentioned that I could use three wires. Could you draw me a diagram?

3. How do you get the photos on your post?

The base on one of them has a detailed box for a base.  Several have an extension that would drill down into the layout.

Stay Safe

Harold

 

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Posted by hon30critter on Friday, May 8, 2020 11:28 PM

wolfman hal
Have you used these bulbs?

Hi Harold,

Yes I have used lots of them.

wolfman hal
At a penny apiece I get nervous.

Yes, after re-reading the ad I'm a little skeptical about that too. I think the pricing may be misleading. I'm guessing that the price is $0.99 for each LED. That is not a bad price, but the minimum quantity is 100 LEDs.

If you are doing signals maybe try these guys instead:

https://www.ebay.ca/itm/20pcs-Pre-soldered-litz-wired-leads-Bi-color-RED-GREEN-SMD-LED-0605-DT0605RG/352703376925?hash=item521ec26e1d:g:wtQAAOSwxCxT34Kw

Be aware that the wires on these are rather large and you may not be able to fit them all into a 3/32" dia. (HO scale) mast if you are doing double headed signals. The wires on the first LED listing are much smaller.

wolfman hal
The area I need to get into is very small ( Signal Masts ).  Is anything except the wire protruding from the bulb.

There is nothing else attached to the LED except the wires.

If you solder the wires on yourself you can use magnet wire which will fit inside the masts easily even for triple heads. I can explain how I solder on my own leads. With the right equipment it isn't that hard. Here are some un-wired RG LEDs:

https://www.ebay.ca/itm/0605RG-100pcs-SMD-LED-0605-Bi-Color-Red-Green-LEDs-Everest-NEW/202283939298?hash=item2f190ff5e2:g:zYQAAOSwPcVVgo-u

Keep in mind that, if you are using brass, the tube can act as a conductor so you would have one less wire to feed.

I'm curious to know how you will mount your signals. Mine will be in sockets using 6 pin IC connectors disguised as bases, like the ones I did for the club. That will allow them to be removed if work needs to be done in the area, and if somebody knocks one over hopefully the pins will just come apart with no damage done. The IC socket that is mounted to the layout is attached to a small piece of breadboard just to make the lower socket stable. Here is what they look like. This is just a test installation to see what they look like. Normally the circuit board would be cut into the homasote:

Note that the signal above is using 3 mm RG round top LEDs. They are easy to use but the signal heads had to be made a bit oversized. Most people won't notice.

Cheers!!

Dave

By the way, congratulations on making your own signals! When I was making them for my old club I think the cost per signal worked out to about $10.00 Cdn. ($7.00 USD). That included buying ready made ladders, platforms and stand offs from Tomar. Pre-made signals are pushing $50.00 each, as I'm sure you are aware.

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by wolfman hal on Thursday, May 7, 2020 3:00 PM

Dave 

Have you used these bulbs? At a penny apiece I get nervous. The area I need to get into is very small ( Signal Masts ).  Is anything except the wire protruding from the bulb.

Harold

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Posted by wolfman hal on Sunday, May 3, 2020 8:35 AM

That is how I read it to. Thanks

STAY SAFE

Harold

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Posted by gregc on Sunday, May 3, 2020 7:16 AM

wolfman hal

Ok Back to the original question.  Is this wiring diagram above going to do what I want?

1. When the train passes over the detector the light will turn from Green to Red and will turn back to Green when the train clears the detector.. It looks that way to me. Am I correct?

Harold

yes.    from https://heathcote-electronics.co.uk/irdot1.html

To indicate when a train is detected a LED is connected to terminals 5 and 6. This LED lights when the train is over the detector. We supply the IRDOT-1 with a 5mm diameter red LED screwed to these terminals. The IRDOT-1 can also operate a seperate LED which lights when no train is detected (green in the diagram). If you wish to indicate no train is present in this way then a resistor (1K) is needed it is screwed into terminals 2 and 3.

greg - Philadelphia & Reading / Reading

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