Easy Grade Crossing Flasher Circuits For Your Model Railroad
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Easy Grade Crossing Flasher Circuits For Your Model Railroad

August 14, 2019


I’m gonna show you a few different ways
to do grade crossing flashers and how to adjust the speed of them so let’s get
going with this right now i’m Tom Kvichak and this is Toms Trains and Things..
this channel was created to help other modelers who are in need of guidance in
pursuing their dream of building a model railroad now I showed you how to do a
crossing flasher in Arduino and it was really simple was just changing a couple
of lines of code and there we go flashing on there but now I’m going to
show you how to do it with a 555 timer chip and a couple of resistors I’ll show
you how on the Fritzing diagram and the wiring diagram what they look like you
could see the components on this video on the wiring diagram that I have listed
at the end of the video and the Fritzing diagram will be there also on the two
projects that I did I actually did three different projects but I only settled on
two of them so take a look at that at the end of the video if this is your
first time here or a returning viewer and you would like to see more videos
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check that out there I have over 40 playlists in there with over 280 videos
so check that out so let’s get going and see how we do these flashers I have a 33
microfarad capacitor hooked up to this right now
you can see how fast it’s going now if I put a 47 micro farad capacitor in there
it’s going to slow it down a little bit so that’s the 33 now this is the 47
micro farad and this is with the 555 timer chip now
we’re doing the same thing with this circuit right here with two transistors
two capacitors and four resistors in there and it does the same thing and
like let me hook that one up but this is a little bit slower so we can adjust the
speed of that right now I have in this diagram it says 10 micro farad
capacitors and that’s how it’s hooked up we’ve got the two transistors I got two
capacitors going across the transistors from the collector to the base with the
470 ohm resistors right there and that controls the brightness of the resistors
now I got 200k ohm resistors on the base if we try to reduce the 100k we could
see what that does using the resistance substitution boxes I have one over here
the box and then I have this one here both of them are set at 68 K now that
goes a little bit faster let’s see if we could bring it down or bring down the
resistance a little bit more and see how fast it is we’ll go down to 47 K and see
how that does you can see I have two resistance substitution box on here and
that was just to check different resistors real quick without trying to
pull out resistors and everything else just flip the switch and use jumpers on
the other one that makes it a lot easier instead of
having to go and change components on your breadboard now that’s at 47 K so
you can see on this one here with the transistors and the capacitors changing
the value of the tubers Esther’s on their that go to the base of
each transistor as you decrease the resistance you increase the speed of the
flashing and on the other one with the 555 chip you do that with the capacitor
I have both of these circuits running pretty close to but not quite on my
resistance substitution box I only have like right here I only have 47 68 and
100 that I could choose from and right now I have it at 47 and then over here
on the capacitors what I’m using right now let me see this one’s the 33 so I’m
using the 47 micro farad capacitor on that one with the 555 chip now they’re
close but not exactly the same these are a lot harder to build than what we did
with the Arduino you saw with the Arduino on Saturday how easy it was with
just some code to flash the LEDs although this one works and you adjust
the speed with the capacitor right there I’m going to try a different design
which uses two capacitors but the speed is adjusted by the resistor that goes
between six and seven so we’re going to do I’m going to change this design here
and pull this out I’m going to keep these LEDs here and just change this
around right here with these resistors and the capacitors we’re just going to
have to change these around the jumpers are the same from 2 to 6 and from 4 to 8
and then one goes to negative and then eight goes to the positive
and three is where your LEDs come from and it’s split your LED and resistors
split from one goes to the negative and the other goes to the positive so when
it just flips back and forth when one when one is high the other one’s low now
this circuit right here that uses the two capacitors both of them both the
negative side of the capacitors go all the way to ground this one right here
the 22 microfarad goes between the plus and the minus leads and we use the
resistor here there’s a 2.2 K ohm resistor between pins seven and eight
and in between six and seven there’s a 47 K ohm resistor and that’s the one
that adjusts the speed now the 47 K ohm is the same 47 K ohm that I’m using on that
circuit right there so we could use both of these circuits with 47 K ohm and
adjust them by the resistor in the circuit with I like this circuit better
right here this one is off of a 9-volt battery okay this one over here is off
of 12 volts I’m going to put the 9 volt on here and see how it works I played
around with several different designs on there and came out with the best one to
use the last one with the five five five and the two capacitors on there and and
the 2.2 and the 47 K resistor I think is the best one to use with the 555 timer
and the one with the two transistors on there and two capacitors that’s a good
one also if you like doing it that way but those are the two best ones that I
have found there’s many ways that you could do it I searched on the internet
and seen about five six different ways to do
it with the 555 timer and then the one that I have right here I think is the
best one to do you can make your own decision on that these two that I chose
are the best ones for me but it may not be for you so go ahead and check out see
there’s other designs that you could find on the Internet
okay now I have both of them operating off of the 9-volt battery right here the
only thing I changed on this one I had 220 ohm resistors on there but I have a
1k ohm resistor on each one of these LEDs and it seems like the same
brightness as it was before over here as you can see we have 470 K or 470 ohm
resistors on these LEDs right here but we could add a second set of LEDs on
second LED on each one of these and it will still work let me pull one off of
each one of these and we’ll just show you how it is with one on each one so
there we go we got both circuits right there but there’s our flashing circuits two
different ways of doing the flashing circuit one with a five five five chip
and the other one with I think these are 3904 transistors you can also do them
with 22 22 transistors and PN transistors and you got two capacitors
here you got two capacitors here these capacitors here are 10 microfarad these
ones over here you have 10 this is a 10 micro farad and this is a 22 micro farad
it goes from the positive right to the negative two different flashers two
different means of getting the LEDs to flash one with transistors are one with
an integrated circuit 555 timer and I’ve got both of them so we can
adjust them with the resistors in the circuit you know I tried one circuit and
you have to use a capacitor to do that this is a transistor diagram and the
only thing that I changed on here is the 100k resistors I reduce them down to 47
K to get the LEDs to flash a little faster now on this Fritzing diagram I
reversed the transistor on the right so the left transistor the flat is facing
you and the flat on the right transistor is away from you you’ll notice that the
emitter on both transistors are on the outside with the black wire going to the
negative rail on this 555 timer chip circuit I left everything as is so the
components you see on here are the same components that hi
used on my example since you can’t stand resistors up on n on the Fritzing
diagram I have the two resistors on the blue and yellow wires laying down but
they are the same as in the breadboard in my example you have to be very
careful when using electrolytic capacitors because they have a polarity
on them so if you hook them up backwards you’ll have very bad results they can be
severely damaged you make sure that you have the plus on the plus side of the
diagram and the minus on the minus side of the diagram they’re clearly marked on
there they have a silver band or a white band on one side that has the writing on
them so that’s the negative side of the electrolytic capacitor I gave you
several different designs of the flasher in this video that if you would like to
activate and deactivate it’s as simple as this battery here with a switch you
could use your own activation in your track or however you want to do it but
it’s just like interrupting the power with a switch that’s all it is and we’ll
cover something like that in the we know later on when we get that far in
the Arduino made easy curve and we’ll see Ya.

10 Comments

  • Reply Donald Whiteman April 11, 2018 at 11:14 pm

    Tom i clicked on your link ARDUINO INFORMATION:
    https://tomstrainsandthings.com/Arduino NOTHING THERE

  • Reply Jack Baker April 12, 2018 at 2:05 am

    Great info, Thank You for the upload 🙂

  • Reply waltworld April 12, 2018 at 10:58 am

    Thanks Tom.  Looks good.

  • Reply M&M Rails April 12, 2018 at 8:55 pm

    Lots of information here Tom. You lost me at Arduino. Lol. -Mark

  • Reply sort187 April 15, 2018 at 10:08 pm

    The flash rate @ 2:37 is the fastest they should be going. Any faster and it just doesn't look right.

  • Reply Doug McKay May 30, 2018 at 11:23 am

    Hi I do love the signed flashing and will be adding the same to my layout. I do have a other power soure from a cumpter power pack witch I will be drawing the power from

  • Reply Mark Bozzano July 29, 2018 at 8:27 pm

    What watt resistors do I use?

  • Reply Michael Morgan February 15, 2019 at 9:59 pm

    Good video. I have a question though. When soldering IC's how would you recommend doing it? Would you use a socket soldered into the PC board, to receive the IC? Or would you have a way to solder the IC to the PC board? Because you can't put heat to those IC's.

  • Reply barney boy March 31, 2019 at 11:07 am

    I bought a flashing circuit board, 5v in 5v out adjustable timing rate, normally open and powered closed output for $2:00 from ebay. Why go to all the bother of stuffing around. It's all on ebay.

  • Reply Errol Aplin June 29, 2019 at 2:09 am

    B

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