JNSF DIY lighting project (PCB based)

[gavino200]

27 minutes ago, chadbag said:

If people want I can sell/send the boards out now though they won't yet be documented.   I can include some photos of my samples and the circuit layout.

 

 

That would be great. I'll take a bunch. 

 

[cteno4]

I’d take 10 to play with!

 

jeff

[chadbag]

I'll dig them out tomorrow and figure out what I paid and make a post. 

 

 

[Martijn Meerts]

I'd be happy to take a few as well, but I can also wait until sometime later. Not like I don't have a ton to do already anyway.

 

[Yavianice]

I'd also be happy to try a few of them, but no rush. 

[chadbag]

This is what I have.  In the image below, the top white-colored, long board is the normal board.  This is the V2 and has lots of room for capacitors so if you have smaller value ones you can use them here.  It has a reasonable "anti flicker" depending on your capacitor values.  It is made so you can adjust the length without ruining the circuit, to work with whatever size wagon you need.  These are 65 cents (US) each.

 

The next white-colored board with the cut-outs in it are for use with "LED Strip" material.  Basically cut off the length you need, and solder the leads to the board.  Has fewer capacitor spaces so you need higher value caps for reasonable "anti flicker".  Depending on what sort of LED strip you use ("5V", or "12V", the resistors needed may change as these LED strips have different values of resistors already on them).  These are 45 cents (US) each.

 

The black small board is similar to the "LED Strip" board but is meant to hook to "factory lighting" like KATO or Tomix, to provide some sort of "anti flicker" for them.  Again the space for capacitors is limited so you need higher value ones.    These are also 45 cents (US) each.

 

The bluish-colored long board at the bottom is the V1 board.  It's anti-flicker is not as effective though it still provides a small amount.  It would be more for DIY boards where you don't care as much for anti-flicker.   Since the anti-flicker doesn't work as well, if anyone wants one they are 25 cents (US).

 

Just message me personally if you want some and I can figure out the actual postage costs.  I will charge actual USPS postage plus 15 cents for a padded envelope.  I can accept paypal friends and family or you can add in the PP charge for normal PP.  I can also accept money orders etc through the mail.

 

If we ever get around to mass producing these (like 1000+) the price per unit should go down substantially.  These were done at a "sample" rate of low quantity and higher price.

 

I'll post some completed boards I've set up and used that will show sample values and I'll try and write up some documentation on what values each had.  You kind of need to experiment for your own needs and expectations.  (Some people might want brighter lights, some more realistic lower levels, etc).  I'll also re-post the circuit diagram and some notes.

 

For capacitors you'll usually want 25V parts or higher, though you can use 16V parts as long as you put the zener diode on the board (there is a spot for it).  This limits the voltage to 11V or 12V (or whatever) depending on the diode you use and should be safe.  I've been running some samples with 16V caps and the diode.

 

I've been using the "hot plate" method to attach the parts to the boards using a solder paste.  I also have a "re-work" station with hot air that I use to "fix" things.  (Once I install a new fuse holder -- the one it came with self destructed from crappy plastic syndrome).

 

Edited May 3, 2020 by chadbag

[chadbag]

I was pretty sure I had put a few V2 boards together in trains but all the Hikari RailStar wagons I opened had V1 boards (or a cobbled together one using a piece of LED strip).  I am still looking for the V2 boards I had put together.

 

 

[chadbag]

Here are some V1 boards (and one wagon with a home made LED strip based on to test the circuit) installed in wagons from the Tomix Hikari Rail Star 700.   Shows different lengths of boards as needed.  V2 board works similarly -- you can trim the board length.   But I can't remember where I installed my V2 samples I put together, yet.

 

 

 

Edited August 19, 2020 by chadbag

[paolo]

49 minutes ago, chadbag said:

 

 

This one looks rad! 😄

Oh wow, I can see you put a lot of capacitors. I wonder if the only one I put makes any difference, probably not.

 

[chadbag]

On 5/13/2019 at 9:59 PM, chadbag said:

I was finally able to take some time to assemble a V2 board (it's been a busy week) (with 12 of 14 LED slots used).   I used all 21 capacitor positions as a test (you can leave ones you don't need empty).   I used a bunch of low capacity capacitors and only had a nominal 367 uF and it wasn't enough.  I added 300 uF more and it was OK.  I think 700-800 uF with 12 LEDs will work ok for momentary anti flicker. Using fewer LEDs means you need fewer capacitors.

 

I used a 5V regulator and only 1.2k ohm dimming resistor (as I am experimenting with this new circuit).  I need to test it for brightness but I will probably be making it more dim (which should increase the length of the anti dimming capacity).

 

But the board works.  So that is good.

 

Here is a picture of it lit up.  This is without the extra capacitance I added (as I just used some big electrolytic ones as a test).  For some reason my hot air rework station would not power up so I just used my iron to fix one bad solder joint on a resistor and to add the big capacitors to test with.

 

 

 

 

 

 

This is the only board I could find though I swear I had made a couple more.  Maybe not.   The one in the quoted post from last year is the same one in the pictures I attached below.  I did not yet snip off the end but you will notice I did not put LEDs on the last two pads.  Because the LEDs are in parallel you can just snip off the ones you don't need (or skip spaces if you want them further spaced apart).

 

Here are the values I used and other observations

 

All resistor, capacitor, and LED pads are set up for 12/06 or 08/05 sized surface mount components.  They should all fit.  Unless you are using tantalum capacitors, the polarity does not matter for the ceramic capacitors and the resistors.  LED polarity does matter.

 

SP1 and SP2 are for track power.  This can be DC or DCC fed.  A bridge rectifier  (D1 on the board), the black square IC right at the end, makes it all work and output the voltage, with a small drop, into the circuit.  You can use 12V, 14V, 18V, etc.   IF you want to leave the bridge rectifier OFF, you can feed it with DCC 12-18V (not DC) on the two pads shown on the board in the middle of where the bridge rectifier chip goes.  SP3 is GND and SP4 is 12V.  This works because your decoder has a 12V and a GND output, and does not switch back and forth like DC does (DC switches which rail is 12V and which is GND when you switch directions).  I just put the bridge rectifier on all no matter what myself, but if you hardwire a decoder onto the board you can actually leave the bridge rectifier off.

 

You will see two small holes labeled PIN1.  Those are the same as SP1 and SP2.  They are in case you want to solder in some of those PIN segments (female or male) so that you can attach power to it using wires with the opposite PIN as you place on the board.  If you want to not hard solder your power feeds but use PINs instead.

 

D1 -- bridge rectifier.    MB6S.   You can use any others in the same form factor/pin out.  I've used MB1S and MB6F as well on other boards (V1 boards which are a similar, not as optimized, circuit).  The MB6 series are 600V rated and the MB1 series are 100V rated.  There are other ones with other voltage ratings in between that you may find.  They will work as long as they are the same package format (physical packaging) and pinout.

 

U1 -- this is where the voltage regulator goes.  There are two sets of pins (the three square ones on the left and the three long thin ones on the right).  The sample board uses the ones on the left.  The order of the pins between the two formats are not the same so match whatever voltage regulator you are using to make sure they have the right pinouts.  The large square pads on the left are SOT-223 package format.  I forget what the ones on the right are --  need to look through my stash of components and find my voltage regulators that fit that side and see what they are :).   The ones I used here were AMS1117-5V in SOT-223 format.  You can also use the 3.3V version.  I have tested V1 boards using the 3.3V as well.  There are some other brand voltage regulators in the same SOT-223 package format and pinout order that work as well.  Just make sure they are 5V or 3.3V.   And make sure that you bend any ground tab on the other side of the voltage regulator up so it does not short anything.  That is typically used on higher current uses where the extra ground allows heat to be bled off into your system.  We don't need that and don't want to short anything out.

 

http://www.advanced-monolithic.com/pdf/ds1117.pdf

 

D16 -- Zener diode.  Plus is on the left (towards the end the diode is on).  Use a 10V or 11V or 12V one to force the voltage in the system to not be higher than that (within reason -- I've seen, depending on the resistors on each end, the voltage be a little higher than rated -- I don't quite understand how they work so cannot explain more).  They come as little glass ampule looking components and also as more standard looking surface mount in a plastic package.  I have both but have only used the glass ones.  Make sure you don't put them in the circuit backwards as the POP really nicely.   If you want to leave the diode off, just short the two pads shown for it with some solder or a small wire.  You can also leave off R1 and R4 (again shorting their pads) if you leave the zener diode off.  If you leave it off, use a min of 25V rated capacitors and preferably 35V rated ones.

 

R1 and R4 are surface mount resistors.   They affect the zener diode.  I used:

 

R1 -- 100 ohm

R4 -- 51-52 ohm

 

Anything in those ranges should be ok.  A 120ohm in R1 and a 47 ohm (or whatever is available near the 52 ohm) would probably be ok.

 

R2 and C10 smooth out the voltage coming from the capacitor bank into the voltage regulator.

 

R2 -- 100 ohm.   Again, anything in that general size should be ok.

 

C10 -- 0.33 mF .   My example actually uses a 0.22 mF Tantalum as I had those on hand to use up. 0.33mF is better but again, 0.22mF is fine if you have them.  Use ceramic if buying new components.  I just happened to have the tantulum on hand.

 

C11 -- 0.1 mF.   This is part of the output of the voltage reguator -- to smooth it out.  0.1mF is what is recommended by the voltage regulator makers.  I've seen other similar values used.

 

C1 - C10 and C12-C23.   This is your capacitor bank.   The sum of the capacitance numbers is how much energy storage the system has for anti-flicker.   700-800mF should work fine in most cases and give a couple seconds of light once power is removed.  Smaller amounts will not last as long, which may be fine for what you are trying to do.  The reason there are so many places to put capacitor is that the ceramic ones don't come in particularly large sizes in the small form factors and it also allow you to use up existing stock of capacitors you may have on hand.  Since they are additive, you can use your small value ones up by adding them to the circuit.  The sample board I shoed used a bunch of smaller ones I had on hand.  You should use 25V or higher rated capacitors.  If you include the zener diode (above) you can use 16V rated ones.  10V or 11V diode is better than a 12V if using 16V capacitors.  I've not had any problems in my test with the 16V and the diode.

 

You do NOT need to fill in all the capacitor spots.  Just as many as you need to get the value you need with the capacitors you have.  If buying new capacitors, buy the largest value 1206 ones you can (the next size up may work??? there is a 1210 size which should also be fine).  Just make sure they are at least 16V or higher rated if using zener diode and 25V or higher rated if not using a zener diode.  You can skip spots too -- place them every other Cx spot if you want if it makes it easier to assemble and you don't need to use all the spots.

 

R3 -- This is the dimming resistor.  I used 1.2k ohm in my sample.  With a 5V regulator, 1206 LEDs, this was a little bit bright and I might uses a slightly higher value.  You can buy little surface mount variable resistors that will fit there.  You may want to put one that goes from 1k -- 2k or something to find the value you like for brightness.  Once you have that figured out you can use a resistor of that value (or the closest one to that value) on future boards you build.   If you use a 3.3V regulator, or 0805 sized LEDs, you will need a different size or range of sizes for the dimming resister.

 

D2--D15.  The LEDs.  You can use 1206 or 0805.  1206 are brighter than 0805 (due to size).  So your dimming resister may be a lower value with 0805 sized ones.  You can use any color of LED you want.  You do not need to fill in all the LED locations.  You can just go as long as you need and snip off the end.  You can also skip spots if you want them further apart.  Unless you install a diffuser of some sort, you can tell from outside when they are further apart.  Even with a diffuser you can if they are bright enough,  (a piece of white paper cut to size over the board would work -- this does not get hot enough to be a fire hazard -- do at own risk!!).

 

 

I use the hot plate method to actually make these since I do not have real surface mount tools.   For fixing things I use a hot air re-solder station.  I bought a cheapo hotplate from Amazon for like $35.

 

I use solder paste that comes in a syringe.  Just put a small dab on each pad and place your component on the pads on the solder.   Once everything is placed, heat your hot plate up to 350-400F (depending on what solder you use -- get the min heat you need from the solder specs -- but you'll want to make it a bit hotter to make sure the solder melts fast).  Place the board on the hot plate.  You'll see the solder melt everywhere (and a bunch of smoke as the rosin included in the paste "burns" off).  Remove immediately and let cool.  You'll probably have components move some in the liquid solder before it solidifies.  You can fix that with the hot air re-solder station.  Just heat up that one component and when the solder melts use tweezers to reposition the component.  With practice you'll get to where you have no or hardly any components move on you.  The trick is to use just a small dab of solder on each pad.  The less solder you use (don't over solder) the less movement you'll get when it melts or you remove it from the hot plate.

 

Inspect the board with your magnifying glasses / reading glasses / loupe etc.  You want to remove any small balls of solder that form (again, with experience you'll figure out how to use less solder in the first place which limits the ball formation).  Inspect to make sure there are no shorts anywhere.   Then get a 12V source and apply power.  Hopefully it works and nothing blows up 🙂  .  I've only had one board not work and I eventually found the small short on it and it worked.

 

My first board took 50 mins (It was a V1 board but the assembly procedure is the same).  Now I can do 4 in an hour as long as I prepare my workspace and have the components segregated and ready to place -- don't have to go searching for each component as I get to it.

 

A hand held infrared thermometer gun is useful for checking the temperature of your hot plate.  They do not heat evenly so you'll want to find where on your hot plate is the temp you want.

 

 

 

Edited August 19, 2020 by chadbag

[chadbag]

7 hours ago, paolo said:

 

This one looks rad! 😄

Oh wow, I can see you put a lot of capacitors. I wonder if the only one I put makes any difference, probably not.

 

 

that one is the same circuit more or less but uses a manufactured LED strip segment (those long LED strip things you can buy and cut up) and a patched together set of components.  Basically to test the idea of using an add on board with LED strip segments.  I have a version of the V2 board made to attach to LED strips instead of your own individual LEDs.  And a version that should work (not tested) with Tomix or KATO or other brand lights as well.   You can look at earlier posts to see those versions.

 

Edited August 20, 2020 by chadbag