starting off today's video with a black lager from little brown jug brewing in winnipeg
they describe it as unexpectedly light roast malt flavored dark color herbal multi-aroma and a clean
crisp finish a little brown jug typically well they're they're best known for their 1919 belgian
style but that's not generally a style that i prefer but i'm interested to see what this
black lager tastes like yeah it's a bit lighter than stouts and porters but the malt still comes
through quite nice so today i'm taking a look at something that i found in my local dollar store
now that it's october the halloween things are out so let's uh rip into this little led strobe light
same thing interesting on the back no just the warnings
so i guess first thing let's just see what this one does when you put batteries into it
there's one little battery compartment screw in the back really soft chewy plastic not surprising
two triple a's okay might as well stick with the dollar store theme and use dollar store aaa
batteries triple a cells somebody's going to be pedantic about that okay what happens here
oh so it's not exactly strobing it looks like it's kind of circulating amongst the three leds
i'm not sure but it looks to me like this led is a slightly different color than these two not sure
if you can see that on camera or not or maybe just my color blind eyes are lying to me i'm not sure
anyway that's enough of staring into that let's uh take a peek inside and see what makes this
thing tick so there's three screws in the back of it um not much difficulty to get in
and as usual they're just self-tapping screws right into the plastic okay so we have
push on push off little button there we have a circuit board with the three five millimeter leds
and we have a disappointing anonymous little blob of epoxy covering the cob
well that's disappointing i guess it's kind of predictable but it's disappointing so
since i've got time left let's bring in an old-school strobe light this is an old
xenon strobe light that i've had since i was a teenager back in the late 70s or early 80s
now it's not showing very well on the camera
let's speed it up a little bit here
yeah it's the frame rate's not working well with that okay fine
whatever switch it off and unplug it because this one is mains powered um
because i've used this as part of halloween decorating the past i've just got an orange
gel on the front of it just to so that you don't get that whitish blue flash in the yard to get
more of an orange flash this particular one apparently was made in dorval Quebec
i thought that i remembered buying this
radio shack decades ago but it's entirely possible that i'm mistaken on that point
being a Canadian device it is held together by robertson screws as it should be
just again self-tapping screws just into the particle board wood
and there is the circuit
so the reflector is just kind of papery cardboard with some sort of metallization on it and just
lumber glued together cheap laminated vinyl on the outside
but that's not the interesting bit the interesting bit is in here and i'm seeing a
massive capacitor there which i think i will discharge if i can
it goes between there and there good thing i did that
are there any other things that uh could hurt me here a big power resistor
some smaller capacitors i don't think those things can like bite me
where's that capacitor to go no okay it's once more for good measure on this dude here
wow that was uh i guess moderately expected i suppose uh how do i get into this now
so there's two screws there that go up to there and those uh those screws have been
chopped off after they go through the nuts so well we'll see if that will come out or not
i'm still a little scared of this
after seeing that capacitor hold its charge oh yeah that's going to be hard
there we go
that's some long aluminum spacers okay so what do we have here
it looks like that capacitor was replaced at some point in history
it's got a price tag on it for a whole 69 cents
um and it also looks like i may have modified this decades ago just to add some serious resistance
uh into the front of the pot to try and slow it down hmm don't remember doing
that but that doesn't mean i didn't do it because i don't think i bought this used so
anyway um have the ac line coming in here uh one side of it goes through this 100 ohm resistor
or that beefy track is there a diode on there yeah okay there's a diode there
um so here is the other side of the the line hmm i'm going to uh draw this out
but just the uh the short and curly here for a minute uh we got two diodes there we've got
a transistor looking device a couple of um capacitors the big electrolytic capacitor
that series resistor on the incoming side this is going to be an inductor
transformer probably which boosts the voltage uh coming from the capacitor i'm guessing and uh
yeah and then this wire here goes to the trigger uh pin of the tube here
this tube is kind of constructed like a neon tube except for it's filled with xenon gas
um and it kind of works the same way it conducts through the gas and you see a nice bright
spark in there the difference being this one only discharges a single time per operation
um anyway uh yeah oh i'm going to draw the schematic of this out and i'll be back in a minute
or two here later that same evening well that was surprisingly difficult to reverse engineer for
such a simple circuit mostly because i couldn't find part numbers and stuff um let's just take
a look through this guy so this is the schematic as it was originally created not uh including my
little add-on resistor there let's pretend that doesn't exist so ac line comes in here over there
goes through that big chunky 100 100 ohm resistor through a 0.1 microfarad capacitor
and then to one side of
this little trigger transformer here which is this little three-wire dude
the other side of the line goes through a bunch of different paths
goes through the resistor and the end 330 k resistor so the variable in another 3.3 here 330k
that's that guy there and that goes up to the gate of the triac
sorry that's not a triac it's an scr and i'm a little confused by that because
there should be some kind of a threshold there so i'm not quite sure what's going on
but that is where it goes anyway um the uh the big ass capacitor down here is charged
through this diode and uh this capacitor in this capacitor here back to the line um
when this scr gets triggered and i'm still not clear on on this exactly
it basically dumps the capacitor through one side of this transformer the primary the secondary has
got a much higher number of windings and that goes out and hits the the trigger
where is it there it is hits this this trigger here and puts a very high voltage spike across
there which allows this guy to conduct briefly and that is essentially the tube
is essentially across the ac means so it's got a 120-ish volts ac so whenever
this guy triggers it just conducts briefly i mean that's mostly what's going on here um
it doesn't match with with a lot of the schematics that i found online a lot of them will use
either a uh either a neon bulb or a diac or something as the threshold to trigger this
but this scr silicon controlled rectifier is a little odd it's not one that i've seen before
it's capable of passing 1.6 amps through it which is reasonable enough for a t05
device which is that package that metal can there but its gate voltage is if i'm reading the data
sheet well it's not really a data sheet it's just a product listing but if i'm reading it right
it's like 0.8 volts to trigger it and like 3 milliamps so that's nothing but i am guessing
that that voltage is relative to the uh one of the the mean terminals which has a dc path
actually no it's not even a dc path there's an ac path through there ah there it is
uh i i still don't quite understand this circuit i'm just trying to figure it out on the go here
so as i said there's a bunch of different ways to do this circuit and i haven't been able to
find one that looks like what i've drawn up on mine anywhere online many of these use
various different types of triggering this particular one's got an external trigger
through an optical or to trigger the scr this one uses a 555 to create the timing
this one uses a neon bulb which is very very traditional way of doing it
um as voltage on the across this neon gets up to about 90 to 100 volts or thereabouts
it will conduct which allows voltage to be on the gate of this scr and allow it to conduct um
allowing voltage to pass through the primary side inducing a large in this case it says
4kv spike into the trigger which allows the voltage to pass through which excites the gas
and allows this to conduct the spark which you see as the strobe light there's another slightly more
simple simplified one but again with a neon this one's using a scidac this one's using two diax
this one's using a diacon triac the the thing that they all have in common is the flash tube with its
trigger input and this transformer which converts a you know few hundred volts spike on this side
into the kilovolts spike that it needs to trigger the flash tube
so it seems that there's as many different ways to do this as there are people designing the circuits
and and this triggering section still confuses me a little bit but i'm willing to be okay with
that at this point because this is instead of decades and decades old circuit and the
majority of strobing unless you need really really powerful ones seems to be increasingly
done by leds like this little thing these days it is kind of fun to play around with but it's
also kind of scary because you've got this 100 microfarad capacitor charged up to the full line
with the full rectified line voltage anyways i'm uh i'm just going to put this thing back together
but in the meantime i'd like to thank you for stopping by and
watching any questions and comments down below as usual i'll talk to you later