Reed switch accessory activation

[corksean12]

Hey all,

I've posted this question in the Model Railroader forum next door and they suggested I ask here for better answers.

I've seen people have interior lighing circuits inside model passenger cars that are activated with reed switches by waving a magnetic wand over it,and  I'd like to build some of these circuits myself.I know Rapido sells these circuits but I feel $15 each is a bit much. Can anyone provide me with plans or a schematic for these? I know I've seen plans for momentary switch activated circuits but I can't find them now.

Thanks in advance,

Sean 

[altterrain]

The reed switch just replaces an ordinary switch making momentary contact when a magnet passes over it. Keep the magnet on it and it stays closed. How about $2/each or less - http://www.bakatronics.com/shop/item.aspx?itemid=450

-Brian 

[corksean12]

this isnt really ideal. I can't really have magnets on top of all my passenger cars every time I want to have the lights on! what I need is something along the lines of a (bistable?) flip flop I think, that I can use an LED and a reed switch with.

[g. gage]

This is ironic they sent you here, I knew a friend when I was in HO a number of years ago that used a reed swtich to turn something in one of his cars. He'd wave a magnet over the car to turn it on (coross ways as I recall). To turn it off he waved the magnet over the car in reverse polarity. As I recall the circuit was simple, the battery, reed switch and load (lamp) in series. The reed is in a glass envelope and in his case it was mounted so the reed moved from side to side. He bought it at Radio Shack, as I say this was  some time ago.

Hope this helps, Rob

[hoofe116]

 Cork,

There're two ways of looking at this problem: 1) do you want to hunt around--possibly a lot--to find a circuit or cajole someone into drawing one up for you, then go find the parts and assemble, or 2) do you want to lay your money down and walk out with what you need?

I did that with R/C, feeling the prices were exhorbitant. They may be, and then, they may not be. I decided to go with DC track and solved the problem that way.

There are websites that introduce you into basic logic arrays. I think in your case you want a JK flipflop. (Emphasis on 'I think'. ) So, go look up JK flipflops and find out. They are basically a mono-state switch. To activate, you'll need the specs of the circuit, the appropriate power (battery?) and some sort of coil to act as a toggle. The logic is usually 5V. (3-5 for reliability).

There are also 'Simple electronic circuits for the Simple' or somesuch on Amazon. I'll go look and see if I can find something like what you're after.

I lean to IR-triggered circuits, personally, but if you're running outdoors, forget that.

I've always wondered why Kalmbach never published a book on circuits dedicated to model RRing.

Les

[corksean12]

They said that larger scales often use reed switches to activate lights and such. I havent been able to find a diagram of a simple JK flip flop yet, so I might buy one of the rapido lighing kits, to see if I can figure out how they did it and replicate it from parts at radio shack if I cannot find a schematic/plans .Thanks for the help guys.

P.S. theres a way to do this with IR? How? wouldnt it still need a JK flipflop?  

[altterrain]

The Bakatronics site I listed above has a number of IR activated circuits.

-Brian 

[hoofe116]

Cork,

Ummm ... yeaaahhh.

My thinking was, the coil might be a PIA to wind, to generate enough 'lectric to trigger the JK, but a simple transistor amp with the coil would (might?) do the trick. With IR, 'blat' you hit it, it's on. 'Blat II', it's off.

I looked in my book "57 Simple Circuits for the Evil Genius". It didn't discuss JK's at all, but used an AND gate array. (You get four gates/chip). With AND, NAND & NOR gates, apparently one can conquer the world.)

Anyway, you have a good plan IF the manufacturer put the chip number on it--sometimes they use an in-house part #, though they might give it to you if you call or write.

OTOH, as I allowed, you could take your $15 down to the train place....

Anyway, no one ever did opine as to why Kalmbach has never published a 'Basic Circuits' book for model RR'ers.

FWIW, I looked on Amazon and the 'Basic Circuits' Book I was speaking of will cost you ~ $125.00. No used ones. If one got the ISBN and went to the Libarry, one could probably get the circuit that way.

Les

[Anonymous]

Sorry guys but picking up power from the live track I just use a mini toggle switch and where the car needs to come up if a bulb burns out I use disconnects so I can get what I call the whole clam open (top & bottom) KISS.

Toad

[hoofe116]

Cork,

Here's all I've got on electronic circuits:

http://www.play-hookey.com/digital/electronics/dtl_gates.html

http://www.hobbyengineering.com/

http://kitsrus.com/cob.html

http://www.openbookproject.net//electricCircuits/

http://home.cogeco.ca/~rpaisley4/CircuitIndex.html

http://www.robotobjects.com/Default.asp

http://www.goldmine-elec.com/

http://www.trainelectronics.com/products.htm

http://www.play-hookey.com/

http://www.goldmine-elec-products.com/products.asp?dept=1031

http://www.lvr.com/microcib.htm

Some of it won't do for you, but one might.

Les

[hoofe116]

Cork,

One last thought: You can use a 'touch switch' approach to lighting up. Like the common lamp. All you need is a place to mount two little rivet heads--or anything else metal, that you can bridge with your fingers. Perphaps the roof is screwed on with two screws? There are circuits in the list I gave you that will (er, should) then turn your lights on.

That's it. I'm outta here!

Les

[hoofe116]

Cork,

http://ourworld.compuserve.com/homepages/Bill_Bowden/homepage.htm#menu. Go here and look on the lower right-most column, 'contolling relays with logic' or sumsuch name. It'll open a window with four simple transitor relay controls.

You take it from here.

Les

[hoofe116]

Sorry guys but picking up power from the live track I just use a mini toggle switch and where the car needs to come up if a bulb burns out I use disconnects so I can get what I call the whole clam open (top & bottom) KISS.

Toad

Toad,

That is so ........ retro.   

Les

 

[Anonymous]

Sorry guys but picking up power from the live track I just use a mini toggle switch and where the car needs to come up if a bulb burns out I use disconnects so I can get what I call the whole clam open (top & bottom) KISS.

Toad

Toad,

That is so ........ retro.   

Les

 

I would rather talk to Elders (retro) and do simple plans than do a freaking birds nest of wiring. If it is retro leased I can tell you where the problem is quickly. Seek more wiring Les!

Retro Toad

[corksean12]

Thanks for the wealth of information and all the links guys.I ordered a rapido thingy,hopefully it will give up its secrets. if not, I might just go with Toads idea as a last resort.

[hoofe116]

Sorry guys but picking up power from the live track I just use a mini toggle switch and where the car needs to come up if a bulb burns out I use disconnects so I can get what I call the whole clam open (top & bottom) KISS.

Toad

Toad,

That is so ........ retro.   

Les

 

I would rather talk to Elders (retro) and do simple plans than do a freaking birds nest of wiring. If it is retro leased I can tell you where the problem is quickly. Seek more wiring Les!

Retro Toad

I, unfortunately was born with a birth defect in my brain: I can think of complicated ways to do stuff, but the KISS principle escapes me. Every time.

Today I finally got to work on the model shop. (A cool name for 1/3 of the laundry room). Finally.

Elder Retro Les

Within the body of an old man is a young man ... wondering what the hell happened.

[hoofe116]

Cork,

I was lying in bed thinking last night. You have a good idea going: what if you hung an electromagnet on a suspension bridge/tunnel mouth/whatever, disquised as you like, so that when the train cars went under (you're pressing the button to energize the magnet) each car in turn would light up. Let the 'mag go dead and the cars stay lit until you run 'em under again.

I am going to file that away for future reference. My era won't need much more than a lantern on a caboose, but it'd work for a whistle with a settable delay relay, or any other action you might think up, like a sound chip and speaker buried nearby to mimic the sound of a small animal being run over....

With an electromagnet, it wouldn't happen every lap, like the buried-in-the-gravel magnets.

Kinda one of dem nights....

Retro Les

[grandpopswalt]

sean,

How about a N.O. (normally open) reed switch at one end of the car and a N.C. (normally closed) reed switch at the other end. Both are wired to a DPST (double pole/single throw) relay, one N.O. contact activates the lamp and the other N.O. contact is wired around the N.O. reed (called a latch). In series with the latch is the N.C. reed which will break the latch. Pretty simple and very inexpensive. 

If you think this might work for you I'd be happy to e-mail you a simple wiring diagram.

Good luck.

Walt 

[corksean12]

That sounds very interesting,If you could show me a diagram that would be fantastic!

[dbodnar]

Sean - I wrote a detailed article that may be just what you are looking for.

Have a look here:

Articles

Scroll down to the LED articles - the one you want is titled:

LEDs 103 - Turning them On and Off

 

Please let me know if you have any questions.

 

dave

[hoofe116]

Mr Bodnar,

I'd buy you all the beer you could drink in one go, just for publishing this data/site. I've been looking for circuits like this for over a year. I knew of the Picaxe, but the price I got quoted for one is in the $50 range. That's a little rich for my needs.

Is there a site that discusses Basic Programming? All I've ever done was a bit of machine language (octal) coding--like maybe 30 years ago.

Also, doesn't one need a computer interface board to program this chip? Note that I only scanned some of the articles, so it may be mentioned. I'll come back to the site when my mnd's clear(er).

Thank you, thank you,

Les W.

[grandpopswalt]

Dave,

Did you do an electronics seminar at the ECLSTS 2-3 years ago?

Walt 

[dbodnar]

Les - the PICAXE that I use most frequently is the 08M and they can be had from a number of sources for $4.00 or less - no programmer is needed.  Only a serial port (or a USB to Serial adapter) and a 3 wire cable that it trivial to make.  The programming software is free and easy to use - the documents that the PICAXE folks have on their web site are excellent learning tools - there is also a book (just go to Amazon and search for PICAXE) that will get you started - lots of resources on the web, too.

 If you have a programming background you will pick up BASIC in no time.

There is an article on my home page that goes into a good bit of detail about how to set up the  PICAXE - go to davebodnar.com and click on Robot Train Project.  There are also a number of articles on using the PICAXE on my other web site TrainElectronics.com

 Let me know if I can help.

 

dave

[dbodnar]

Walt - that was me - I have done seminars at the ECLSTS for the last 5 years or so - also at the SELSTS and a number of the National Conventions.

The notes on those presentations are on my web page at TrainElectronics.com

dave

[hoofe116]

Les - the PICAXE that I use most frequently is the 08M and they can be had from a number of sources for $4.00 or less - no programmer is needed.

//AAAUGGHHH! ALL THIS TIME WASTED DOPING OUT AND/NAND/NOR GATES  and then trying to make 'em work with transistor drivers. I'm a retired tool and die maker, but I worked for/with elektrical enjuneers to develop 'engineering prototypes'. (Read, "Uh, Les, we don't know quite exactly what we want, but could you make X with Y radius and Z tolerance? We need it to do this and thus, but NOT Thus and this.") Turned out I could. Talent on loan from God.

Electronics? Nah, not so hot here.

I know just enough fumble my way through. On occasion.

 

  Only a serial port (or a USB to Serial adapter) and a 3 wire cable that it trivial to make.  The programming software is free and easy to use - the documents that the PICAXE folks have on their web site are excellent learning tools - there is also a book (just go to Amazon and search for PICAXE) that will get you started - lots of resources on the web, too.

//Oh yeah: I've been surfing the Web for over a year trying to beat the cost of R/C. Case of not recognizing good advice when I hear it. The Aussie that runs RCS(?) is a straight-shooter, for sure.

 If you have a programming background you will pick up BASIC in no time.

//I HAVE NO PROGRAMMING BACKGROUND. I liked what little I did--are you old enough to remember the HP-30 with RPN? I had one of the first ones and used it effectively. I have an RPN brain, I can't use TI's worth a D--er, darn.

There is an article on my home page that goes into a good bit of detail about how to set up the  PICAXE - go to davebodnar.com and click on Robot Train Project.  There are also a number of articles on using the PICAXE on my other web site TrainElectronics.com

 Let me know if I can help.

You could help if you felt comfortable sending me your email addr. I promise not to bombard you with stuff. Mine is   [e-mail].

Les

 

dave

[grandpopswalt]

Dave,

That's good to hear. I really enjoyed your presentation. I'm also very glad to learn that you have a website. So thanks for sharing your knowledge with the rest of us, it's greatly appreciated.

Walt 

[dbodnar]

My email is [e-mail] - easy to remember!  Or you can use [e-mail]

I would suggest, however, that electronic questions that might be of interest to others be posted here so that we can share the discussion.

Thanks!

dave