you remember the circuit board holder from a recent mailbag? well I want to play
with it which means it's time to do a kit build now this kit here is another
variant on a chase lights kind of circuit
it's that led not in the bag press them so it has it doesn't do it the same way
as the previous ones I've done this one chases 16 lights around a circle around
here which is you know whatever that's just cosmetics but it does it using a
pair of these 74 HC 595 shift registers and to clock them of course our old
friend the 555 timer that's not really surprised and there's a surprisingly low
count of components outside of those things there's obviously the bag of LEDs
there's the world's cheapest potentiometer 3 K I think it says on
there there's a couple of pushy buttons a couple of capacitors only Q capacitors
but yeah C 2 C 1 only 2 capacitors okay and a few resistors and all the LEDs so
that should be fairly straightforward but before I just dive right in and
solder it especially since there's no sockets with this I think I want a
breadboard it up at least partially and just see what happens so it's a Brit to
do that I'm gonna need the schematic and I'm just on those thing the eBay listing
that I got this from I found this schematic which I printed out just for
convenience normally I don't like to print things out just because they don't
want to waste the paper because I'm cheap and I don't want paper lying all
over the place wasting space
and everything else around save the planet eat so what goes on here the five
five five is just a very standard five five five circuit variable resistor a
couple of capacitors and and ya win rent that shows three capacitors on it see
what there is a third capacitor where are you oh man I'm gonna have to dive
into my own spare parts talk well that sucks so the two capacitors that I've
got our electrolytic that's these two this one I'm gonna have to go back to
the listing and figure out what it is one two three four fixed resistors yep
one variable resistor yep to push your buttons sure okay so the theory here
with five five five also eats a long square weaving outputs on pin three just
because it does that feeds into okay that's what the capacitor does it's
creating a bit of a timing circuit on the output a bit of a delay on this but
we'll get back to that in a second pin three output to the clock inputs of both
of these both of these shift registers our ground seven or eight LEDs coming
out on q0 through qk m prime is an inverted copy of q7 I believe it's
inverted copy of q7 which comes out passes on to the serial input of the
second chip so what happens when you're when you're running this thing but these
two switches that can one of them can pull the serial in low
this resistor one of them can pull it high through no resistor and that pulls
all right just pulls the one see really like cereal on the first one okay and
then these clock through the output are there comes into the cereal I know this
one it talks through then they open to that one through this limiting resistor
goes back and into the Cyril oh they're so you use these two to put in a pattern
while it's clocking along and then it just ripples through bangs out the back
end comes back in the front end or ripples through that's kinda neat okay
I'm just gonna quickly throw I think just that much together onto the
breadboard and this basically just duplicates that so I don't don't like
that and oh yeah we need to go back to my eBay listing and figure out what that
capacitor is as well it's where are we component list okay
there we go component capacitor C 3 is a point 1
micro farad or aka a 104 capacitor right get the one of the component values for
the rest of these resistors 1 & 2 180 ohm
3 & 4 are 840 ohm okay so grab a passerby mustache here know the
assortment kit that I bought doesn't go down to 104 but I have some old ones 103
104 there we go some old ones just from a random grab bag that I had for years
that should do nicely for this c3 here and the other thing I've learned because
I've been bit before it's just to double-check the resistors yes you could
use the color code but as I've mentioned and
kind of color binds and I don't trust that so that one's a 1k but you didn't
show up anywhere in my thing my schematic that's a 100 oh okay
what are you that also seems like a 1k and you are so I got a 100 mm and three
one case we ate 848 20 close enough close enough anyways and 180 184 are you
there we go those guys out of there great
no let's see if it actually works
okay there's the 5x5 circuit together five
volts over here and it blinks so that's winning the potentiometer you know
that's one end that's the other end next let's get this guy working
all right I think I've got it I'm not going to bother with the switches I just
got a jumper wire in there or right now from the q7 out back to the serial in I
guess it's that seven out back to the Syrians just straight across so when I
turn it on there just whatever random noise was in there I take that off the
output and I'll put it to the hi and everything goes low for it so to the
ground it puts everything high I'm just gonna run all low and then so where this
is coming from that's just picking up noise out of the air just random noise
so I'm gonna do that and then I'm gonna go quickly from the the positive rail to
the shift out and while I'm doing that there'll be a little bit of noise in
there but not much so there it annoys the couple in now you see it's going
across and bang and just like we wanted so whatever pattern that happens to be
two separated by the looks of it cool so the concept works that's neat
and you know I didn't didn't want to do the whole thing on the breadboard but no
let's uh let's get to soldering it now that we know that it works and they were
stupid about these resistors and stuff yeah let's uh let's throw it on to the
real circuit board which is actually the whole point of this video so the first
thing we probably ought to do just just get this actually no the first thing we
ought to do is get a beer guess we're gonna need that got them a beer this
time it is from another brewery that I've not heard of before from Oxus
Brewing Company this is called juice of the Oats oatmeal stout and it is from
you know oxes Brewing Company Winnipeg easy drinking they're here with the
aroma of coffee and chocolate oh definitely even the coffee I'm
getting a lot of citrus in that one - interesting
hey on with the program so as I have said before woundings kit builds I like
to start with the things that are least likely to get damaged by excess heat and
work towards the stuff at the very end that's potential to damage with excess
heat which means starting with resistors and switches and capacitors and then
probably the LEDs and then finally the ICS although none of these are
particularly fragile ICS since I don't have chip sockets and I'm not going to
bother tracking something down I will just yeah be gentle with them so the two
resistors actually the everything's thrown in the 555 the resistors both
180s there they are there so that's our one of our two I'm here come on hurry
r1 there's one of them I'm interested to see how well this little soldering
holder thing works r2 where do you go right there the challenging one is going
to be c2 and actually don't look at that the reason that's gonna be challenging
that's a ceramic capacitor the one that I had to pull out of my stash because
for some reason that didn't come with the kit actually gonna c3 I'm sorry up
there so that is
those two pads they're just telling my thumb I don't I point with a pointer
here these two pads here so the reason it's challenging is because the
capacitor is actually wider than the pitch and it's got very short leads on
it so what I think I'm going to do just to be sneaky is take that one resistor
lead and poke it up through and solder the the one capacitor leg to it yes this
is unorthodox but sometimes you got to do what you got to do pull that tight
there and if it was a high frequency circuit I would be offended by that but
I don't think that's gonna be a problem so that's kind of held in there I think
that'll work but my solder there we go and I've got sort of the medium tip on
there I don't have the finest tip because this isn't the finest work these
are all nice big through-hole pads
there we go that works and I got here this is working pretty well to hold it
stable I don't mind this at all okay so does that look pretty good it's my snips
now this one so the capacitor I'm going to shove one lead down through the board
and if the other one kind of awkwardly up in the air this is just a complete
kludge but electrically it'll work I think that back down into the clamp and
starter down the lead that does work properly here and I'll move it over so
it's one shot here we go now the goofy one hmm not sure tossing that back and
forth you know nota there all the time yeah awesome play out of it let's see
what I've done here did that solder
yeah looks like it's soldered okay taint pretty but it works separate that there
we go yeah oh good but I'll go with it so this is
gonna be our three and our four Oh first casualty okay so this is supposed to be
wedged in the hole there on that one so that this spring can push against it
like that alright that isn't working out
fortunately this board is big enough that it jams against the back there but
see that's not right down in there not sure what I'm gonna do about that
but for the meantime for the purposes of this little project what look like so
far those are all decent solder joints this boards actually taking started
quite well it's the what is that well that's the fennel the the fennel ik fr -
I think I'm slowly starting to get that stuff memorized it's passive is
electrolytic capacitors at two hundred microfarads there's one there's one
or are you capacitors there's one so the shaded side is the negative like that
and I think that this would be interesting because those are sitting
taller than everything else what happens when I put it in the clamp I mean so
they are just that well this one's not touching no they're both just barely
hovering there actually that's not a bad idea cuz it's pushing them up against
the board that's not too bad yeah you can see that it's a little bit
floppy loose with that thing broken out of there I think I'm gonna have to show
something epoxy in there at some point I don't know
next passive thing air is this cheap cheap cheap cheap potentiometer you go
there what else do we want to put on there on the push buttons wherever they
are in this pile of carnage there's one of them yeah they're not see they've got
these the sheep the leads on them so they're supposed to just kind of
mechanically hold themselves in the board for when you flip them over to
solder like that worked either one go it is but I think I miss sheep that one by
ramming it into my breadboard this one clamps right in there nicely now I got
to pay attention to how it oriented in here because I put it this way those
capacitors gonna crash on that little beam there anything
there we go yeah it was a little fiddle defeat in there
no one can mix on this thing if you got all the low profile components
it's probably an oaky thing as soon as you start giving taller components on
the back side of the board you just doesn't want to sit down so that is
everything that's not an LED or a chip okay onto LEDs next so the LEDs the
short one is the negative and the negative is marked as the flat side
which usually is but these LEDs zoom don't all note here these particular
LEDs don't have a flat side so my only indication to the positive a negative is
the length of the leads so just drop all those guys in and get to soldering
okay there's all the only be sat in and it looks like I've got a spare one nice
now then how is this going to work with my holder here because I haven't spread
the weeds out yet let me just quickly do that okay only these are sort of spread
out I'm gonna have to pull up on them but there is no way I'm going to get it
into the grips of this thing because the LEDs keep crashing on it so I'm gonna
have to go back to my old method I guess not ideal but this thing has served me
well over the years and I think I'm just going to go to stay with the rubber grip
so this thing it's got grooves in the jaws for grabbing stuff that's also got
these soft jaws and when you hear mechanic or something you're talking
about a soft jaws it's usually made out of a softer metal like copper or
something these are actually kind of rubbery you know
so we'll start down the bottom here so that was there
here we go
and the last one
there we go
seemed reasonable with the eye sees number one is the five five five let's
fuck that off the breadboard notch goes that way this is the only downside of
doing it like this I'm just trying to get the pins all end up in into the hole
and that always the way they're you know that's not so bad
now will that hold in there I'm going to give one of those pins a little bit of a
knock that way you know another one I'm gonna knock that way that'll hold it
five five five is probably not fragile enough that I need to worry about doing
it last we're doing the ICS last it's just a good habit from the old days you
know the other thing that I'm doing
he's moving my heat around too so I'm going corner to corner and side to side
just to kind of spread the heat load out on most the IC but also on the board
I'm the last one I can do this way okay
to go cook look make sure I haven't created any solder bridges from a couple
of different angles looks good okay no I got left is the two shift
registers exactly the same is this look make sure the pins aren't too horribly
bent that's one that's not you knowing very well they're the dot and the notch
there indicates pin one just goes of that away just nudge him down
no gym into the pin into the walls - there we go that one was even easier
okay no just more soldering and these ones just to hold them in place and just
hit the corner pins ah there we go clean on your happy iron
there we go left again check for solder bridges short circuits not seeing any
what is that hole that's under the potentiometer that's not a big deal all
that's left is to put some kind of power connections on there this out of the box
this should work except for must define Hoyt as the
positive and is that green or brown I don't know anyway it's gonna be the
negative
they real oh sure yeah that's just flux in there okay alrighty it is done so I
got power hooked up yeah these wiggle connectors I still
like them they're great five volts over here three two one go
okay oh that's dazzlingly bright and nothing's happening there huh
troubleshooting one troubleshooting session and a couple of bodge wires
later it works so this is the original board where that doesn't count I when I
wasn't working I cut the track between pin three of the five five five and the
rest of the circuit basically right there there to isolate it and the five
five five still wasn't oscillating so I assumed in even closer and found that
pin seven of the five five five wasn't connecting to the capacitor so I assumed
didn't even closer I noticed at the capacitor of the five five five its pad
was missing notice that before maybe I had buggered it up when I was soldering
but throwing too much heat in or something I don't know but anyway it
works let's flip it over so you can actually see it
dazzling in its brilliance so now then push the one programming button push the
other programming button so that one looks like yeah that one's filling it up
so now it's full except for one spot now I'll push the other programming button
and you know over here it's emptying now we just have a single led in the in the
system rippling through and when it gets to there it ripples through to there and
carries on right okay so there we go that was there's a fun little kit build
and if I hadn't well okay so deficiencies with this kit build first
of all it didn't include one of the capacitors this one here was missing
from the kit so I had to add it and it had mostly the wrong resistors in the
kit so I had to go to my stockpile that's a negative it's using the the
cheaper type of circuit board which what do you expect for as cheap as this thing
was when I bought it that's that's neither here nor there but when you're
using the cheaper circuit board you gotta be a little bit careful with your
soldering technique and not quite so heavy-handed as I was otherwise you'll
end up having to do some troubleshooting and some budging anyway I hope you found
that interesting possibly informative um possibly amusing
laughing at my misfortune that's all fair - thank you for watching I will
talk to you later
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