Thanks all.  I get to fix everyone's stuff, never designed anything wasn't sure of the process.  I already have the parts, wanted to get the boards because I think it will make a nicer package then what I was going to do.

John, I knew you didn't put anything in there, I already checked.   

Gene Anstine

Rod Stewart posted:

...I wonder if its possible to export the electronic cart summary from their site, anyone know?

Untitled

When you have your cart loaded up, look for the "Cart Share" link which generates a unique URL that you can share.

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Last edited by stan2004

I have another question for John/Stan/et al. - but first, Kudos.  I'm sure some of you have seen the missive from Alan Arnold (OGR head honcho) about his growing concerns about the escalation of negative posts in some of the discussions (something I recall Rich Melvin - his predecessor - worrying about).  Fortunately I haven't seen a lot of that and in apparent (and delightful) contrast to that concern has been the very helpful discussions and inputs in this forum on converting passenger car lighting to LEDs.  This is a topic that has been discussed quite a bit over the past several years yet the really knowledgeable and helpful folks like John, Stan and others haven't dismissively said 'we covered that back in "aught six" - go look it up...' but instead have engaged with the various 'new to the topic' folks and those of us that have been in the 'contemplation' stage for a couple of years.  So I just wanted to say "thanks" for both the knowledge and experience, the willingness to offer help, but also the attitude.  Nice goin'...

So my question - looking back at the earlier part of this thread, which is a couple of years old - John, you made a comment about not having anything grounded to the frame (in response to a troubleshooting question).  I'm not sure how Lionel passenger cars are wired up - I'm a Flyer guy and in my case, the track power circuit is typically the 'hot' pickup through one truck which is insulated from the car frame and a wire lead from that truck (usually from the top of the truck rivet) to one side of the light bulb socket.  The other side of the socket is usually connected physically to the metal floor of the passenger car, which in turn is connected to the other truck (uninsulated).  My plan is to take the leads from the two trucks (I'll solder a lead to the rivet on the uninsulated truck or connect it to the frame) as inputs to the AC side of the AC-DC bridge circuit.  Nothing 'downstream' of that connection will electrically connect to the metal floor/frame.  Is that consistent with not grounding to the frame?  I suppose alternatively I could insulate the other truck from the floor/frame - which turns this into a somewhat bigger project.

Thanks,

Rich

FWIW,  Here’s a cart share from digikey on the products for the GRJ-JWA pcb.  I’m very sure as GRJ sez, you can find cheaper prices from Asia.  YMMV

Edit:  I already had the chokes which is why they aren’t included.

digikey Parts

Last edited by TedW
richs09 posted:

So my question - looking back at the earlier part of this thread, which is a couple of years old - John, you made a comment about not having anything grounded to the frame (in response to a troubleshooting question). 

RIch, that comment is on the DC side of the lighting module. Since the frame & center roller go into the bridge and there's a diode between them and the output + or -, you MUST NOT ground either + or - on the output. For a Flyer 2-rail scenario, same caution applies, except it's the power from the wheels. You don't have to isolate anything, just make sure the DC out of the module doesn't connect to the frame anywhere.

TedW posted:

FWIW,  Here’s a cart share from digikey on the products for the GRJ-JWA pcb.  I’m very sure as GRJ sez, you can find cheaper prices from Asia.  YMMV

Edit:  I already had the chokes which is why they aren’t included.

digikey Parts

Did you see this?

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gunrunnerjohn posted:
richs09 posted:

So my question - looking back at the earlier part of this thread, which is a couple of years old - John, you made a comment about not having anything grounded to the frame (in response to a troubleshooting question). 

RIch, that comment is on the DC side of the lighting module. Since the frame & center roller go into the bridge and there's a diode between them and the output + or -, you MUST NOT ground either + or - on the output. For a Flyer 2-rail scenario, same caution applies, except it's the power from the wheels. You don't have to isolate anything, just make sure the DC out of the module doesn't connect to the frame anywhere.

TedW posted:

FWIW,  Here’s a cart share from digikey on the products for the GRJ-JWA pcb.  I’m very sure as GRJ sez, you can find cheaper prices from Asia.  YMMV

Edit:  I already had the chokes which is why they aren’t included.

digikey Parts

Did you see this?

Yeah, backordered, but they said estimated ship was 2/4/19, so I went with it as I’m in no rush.  The boards will take a week or so too.  BTW, thx again for the share, that should work for everyone directly to the order page.

https://www.digikey.com/produc...497-1575-5-ND/591677

Here's a version that is apparently in-stock at DigiKey and less expensive 67 cents (vs. 87 cents).  While I appreciate the convenience of 1-stop-shopping from DigiKey, given the ~2 week delivery time from OSH park, I wonder if going with an eBay Asia source is something one might consider.  IIRC the LM317 goes for less than 20 cents on eBay (from Asia).

Wow, a lot of activity on this thread since it was revived the other day.  

I had time this afternoon, so I revised my version of the PCB layout compressing it as much as possible.  Got it down to 1.08 by .86 inches.  Total area .9288 square inches.  Just like the previous time, OSH Park made the dimensions just .01 inches bigger in each dimension.  Not an issue, just made me laugh.  The price for three boards went down as expected.  Probably go ahead and order another batch of three boards.  Only reason I will get just three is to make certain I can actually populate that small of a PCB without problem.  It has been a long time since I have done any circuit board building.  Last time I did it I actually etched the PCB board using chemicals.

Greg

John - good, that's what I thought (re keeping the DC side of the circuitry isolated from anything that touches the AC side).  thanks

Just received an email from Osh Park that there have been 59 orders for a total of 309 of JWA/GRJ's boards and they expect to get them out by Feb. 5.

Carl

Yeah, that’s the order, but I recommend anyone to search elsewhere because of the price difference.  I even had some of the parts on hand but were not an exact match so I ordered the speced out part anyway.  The LM317T for example.  I have 30 in my bin I paid $4.35 shipped!   Oh well.  And from the page John copied it sez the regulators are available to ship.  I just got an email saying the order has shipped...  

Last edited by TedW

GRJ, don't know why I got what I did when I tried TedW's link the first time; but, when I tried it after reading your post, I got the same screen with part nos., prices, etc. as you posted.

I've since deleted my earlier post.

Carl

gunrunnerjohn posted:

You do realize you can actually truly delete the whole post, click on the Take Action link on your post and use the Delete function.

I find it therapeutic to manually delete incorrect information and publicly acknowledge the error of my ways--but, NO, I never knew I could delete the reply in its entirety--make it disappear which I have now done.

Carl

gunrunnerjohn posted:

Sounds like a more reasonable size, got a picture of the new layout?

Don't get me wrong, I truly appreciate all the help and advice I have received but honestly I don't understand why it's now "a more reasonable size."  I stated that I had never before designed a PCB that would be manufactured for me.  This is all new to me, I am only doing this to attempt to actually complete a project I purchased components for quite a while ago.    It was never my intention to compete with anyone with regards to board production.  I probably would use your board design as many others have if I didn't already have different components on hand.

 

As requested, here is a picture of the revised board layout.

 

PCB Ver 1.0.2

Greg

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You just can't delete  a topic you start after someone else reponds to it also. After replys you could change the title to nonsense and edit the original post to blankness though.

I haven't begun to layout the PCB for version 1.1 yet.  I just added the PTC and the choke to the schematic.  I only rearranged the components on the original board.  It was necessary to increase the board width to get everything to fit on a shorter length board.

Greg

Last edited by GregM

Creating a smaller board may be as simple as knowing a different shape or size  availpiece is now available or as a need of luck like a game of tetris; sometimes you miss a better stacking option.

"Still trying to not shoot my eye out"

 

"Nursing insomnia one railcar at a time"

My aroma therapy? Smoke Pellets.

 





I think one of your limiting factors is your connection pads seem to be too generous.  I think there's where a lot of space could be gained.  Look at the space I leave for power and LED connections and the space you leave.  I think just shrinking those would do wonders for the size of the board, you'd have a much better chance if fitting stuff in a more compact manner.  The rest of your layout seems to be reasonably space efficient.  However, I think you'll find you can also squeeze the components a bit tighter than you have when you get actual components on the board.

What I do to size things if I'm not sure of the spacing is to print a 1:1 image of the board and then set the components on the image to see if I have any conflicts.

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What GRJ said.  For a first try it's quite good!   

If I understand it, your board design program does not have 3-D rendering (?) so it can be hard to visualize how the parts interact without actually assembling a unit.  Back in the day, when designing a board using through-hole parts what I found useful was to place the parts on a 0.1" grid perforated project board.  Of course this kind of measure-twice, fabricate boards-once practice has been turned on its head with what has become zero fixed $ penalty to fabricate revisions.  

perforated project board

Photo shows a couple other ideas.  Those screw-terminal connectors come in 0.1" pitch.  I see you're using 0.2" pitch which obviously take up a good chunk of real-estate.  I realize you already have the connectors but maybe next time if size matters.  Also, for space savings nothing wrong with standing up the resistor like black diode in above photo with pads spaced 0.1".

Separately, on your latest revision when you install the component you cover the silkscreen.  Your software should allow you to drag the white silkscreen reference designators (R1, RV1, J1, etc.) or labels/symbols (AC IN, +, etc.) so you can see them after the parts are mounted.  Note on GRJ's board how lettering is outside the footprint of the parts.  And for your RV1, it's usually customary to have a square-pad for pin 1; or for symmetrical parts like this (can be installed either way) at least some silkscreen indictor showing notch, tab or in this case maybe a small circle showing which end has the adjustment screw.

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Stan,

  KiCad does have a 3D viewer but not all of the components have 3d models so when you view the board there are some components missing.  Yes, KiCad allows the silk screen data to be moved anywhere desired.  Since some of the information will be covered up, I put information on the bottom silkscreen to identify important information such as AC IN and DC OUT and which pin was + on the DC out.  As for the other designations, all the information needs to tell me is what goes where during assembly which is why I numbered the pins on RV1 so I know which way to mount it.  Now that I think about, it might not really matter which way that part is placed provided pin 2 is always in the middle.  (That's meant as humor in case someone miss interprets.)  Perhaps that's why there is no square pad for pin 1 on the footprint since it really doesn't matter.  I didn't create any of the footprints used, I just picked a matching (at least the best match I could discern) footprint from those available in KiCad for each component and placed the footprint on the PCB.

Greg

Greg, if you're thinking of doing more PCB work, I'd encourage you to give DipTrace a look.  They have a free version that's good for small projects like this, and it has a really extensive library.  The other big bonus is I have found it's very easy to create new parts for stuff that's missing from the library.  For the 3D views, you can pick a similar part and very easily stretch or shrink it in any dimension to give you a decent 3D view.  I usually get a pretty accurate representation of my boards with the 3D view.  This allows me to plan the layout and be reasonably sure things will fit.

Here's an example, my Super-Chuffer II board and the 3D view.  The biggest discrepancy in this view is the added socket on the real build, that allows me to easily change the uP firmware without a soldering iron.

 

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GregM posted:

...

Now that I think about, it might not really matter which way that part is placed provided pin 2 is always in the middle.  (That's meant as humor in case someone miss interprets.)  Perhaps that's why there is no square pad for pin 1 on the footprint since it really doesn't matter. 

Hmm.  I wonder if this explains why on the 99 cent voltage regulator modules on eBay that use similar looking blue multi-turn trimpots, some versions have CW increasing voltage while others have CCW increasing voltage. 

John, I don't have any plans to do more PCB design but if I do and KiCad doesn't have what is needed, I will check into DipTrace.

I should not try to type and watch an old episode of Monk at the same time, not doing either very well.

Greg

Last edited by GregM

In case it is of any value here is my final as ordered BOM. It is an Excel file based on grj's BOM, just fluffed up a bit. Note the first is the standard 5-45 ma version and the second is the optional 100 ma version. The latter differs only in the resistors and the C1 cap value. Most stuff I ordered from Digi-Key but the trim pots come from Asia. The ebay item numbers are shown where applicable. My quantities are 50 and 30 respectively; I just want enough on hand to build up to either of those quantities.

BOM Snip 01-27-19

If needed email me offline and I can send you the spreadsheet which you can modify as desired. You can change your build quantities to suit. For now I have ordered only 12 boards from OSH Park, just so I can make sure all is well for fabrication, though I imagine they will be just fine.

Rod

We are never too old to learn something stupid....

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Parts came in yesterday.   Am giddy with excitement.   Where are those boards?  Dang! I just stepped on something slick.  

E7015639-99FA-4A04-8A98-8C4158A7FE3E

 

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TedW posted:

Parts came in yesterday.   Am giddy with excitement.   Where are those boards?  Dang! I just stepped on something slick.  

E7015639-99FA-4A04-8A98-8C4158A7FE3E

 

Video to follow?

GRJ, for complete novices like me, what is the optimum way to go about assembling these "kits"?

 

Carl

TedW posted:

Parts came in yesterday.   Am giddy with excitement.   Where are those boards?  Dang! I just stepped on something slick.  

E7015639-99FA-4A04-8A98-8C4158A7FE3E

 

Video to follow?

GRJ, for complete novices like me, what is the optimum way to go about assembling these "kits"?

 

Carl

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