it's another temu product not a sponsor
I've just been buying various things
from them just to take apart for our
entertainment this one is described as
one piece outdoor camping lamp with
tungsten filament LED bulb for emergency
Nate market and Street store use I think
the key things here are camping lamp
with tungsten filament and it's
available in three different shapes and
it is rechargeable the price varies
according to the shape and the price
does include shipping but there is a bit
of a thing there about abusing the
shipping system
it comes in a box like this with the
light itself and a USBC charging cable
and has helpful tax in the side that is
completely all just mushed together
they've removed a lot of the species and
it says products used to dim the lights
should be prohibited during charging
that doesn't make sense charging time is
approximately four to six hours with the
type C charger or a computer do not
leave the battery unattended while
charging when charging is complete
please also it move the power supply has
discharging function excellent this is
all good to know
in use it has what they call three gears
it's got the little USB charging port
the flap and a little red LED to show
its charging charges at 500 milliamps
and when you press the button it lights
at full intensity and you'll see a
slight posted modulation and then you
click again that goes down to the lower
intensity a bit more puzzle modulation
then click again it goes to the lowest
and maybe a bit more enhanced pulsive
moderation it's still useful levels of
light however the battery doesn't last
long I've tested it I left it for
several hours at the low level and uh it
seemed to go down to a lower intensity
quite quickly but that's okay we can
hack stuff like that it's worth
mentioning that by swiping it brows and
forwards while uh it was lit I showed
that the well I found out that the full
intensity is actually 50 pulse of
modulation duty cycle so theories it
could have gone to higher brightness the
middle setting is about 25 and the
lowest setting is about 10 ish percent
uh impulsive modulation okay let's try
and open this and it is a little that
just squeeze the button there oh it does
actually I thought this was glued this
is good it is unscrewing this is nice
this is what we want good access
uh is there glue in there I like the way
the filament is mounted on these uh
springy supports to give it stress
relief
however it's probably not designed for
the stress I'm about to expose it to by
getting a screwdriver screwdriver
and then just randomly Levering it out
is this going to come out
without a struggle or is there going to
be a struggle
it's kind of coming out
oh
this may be destroyed in the process I'm
not sure if there's something I should
know here
is there a hidden screw
it does have a carabiner in the top
which is the one that uses the
off-center pivot Points to actually
provide the springiness I don't know if
maybe hold on no I don't really see
what if I push down that no that's not
helping
I don't know what's holding this in if
it breaks it breaks
I got this for our exploration it does
feel like it's actually held in maybe
it's just
held in at the sides here
this circuit board does not want to move
that makes me wonder why what is holding
this in place has it been glued in I
don't see any sign of a screw so I'll
just keep prizing and you know what's
the worst could happen it'll break it
will break at some point won't it
okay
so
that was just a friction fit then where
here's the cell here's the oldest
circuitry oh it's a standard double A
sized lithium cell of unknown uh
specification the circuit board looks
very straightforward it looks as though
it's got the well let's take it apart
and well I'll take the picture and we'll
analyze it we'll take a look at the
circuitry and that will uh tell us all
we need to know one moment please
and resume isn't hindsight a wonderful
thing it would have been so much easier
getting the LEDs out of the base here if
I'd known that it kind of been a caps in
but at the factory they must have a tool
that bridges over the filaments and
there's a couple of pins that go down
into here and they basically put it down
and then rotate it and that locks into
position I could try that right now no I
can't because I got wires in it now but
it does I tried it earlier it goes in
and it rotates and that's what locks it
in place then they put a little sliver
of glue in it and this screw this bit in
and it locks it all in place
the lithium cell I've tested it 282
milliamp hour is not good capacity for
this but not to worry it's got loads of
hackability let me Zoom down on the at
circuit board and we'll explore it
very textbook as the classic eight pin
mystery microcontroller with the classic
pinout of the pic 12. and uh it's quite
interesting it's a nice enough design
it's interesting that they've just used
four pins in it and they've just chosen
the four corner pins power at one end
and an input and an output at the other
end
there is the classic lth charge chip
with a 2K resistor that programs account
about 500 milliamps there is a resistor
for the two charge indicate realities
there's a red one and a green one didn't
know at agreement as well
just like if patients not letting it
charge up fully there's a push button
and there's a standard npn transistor
but it could take a mosfet however
they've used an npn transistor and a
couple of 1 ohm resistors in parallel to
give half an OHM
um the coupling circuit for the
processor 10 Ohm resistor capacitor
let's take a look at the schematic
here is the schematic I shall Zoom down
even further in this no great surprises
it's very textbook
but that's okay it's a nice product it's
a nice design it just needs a few tweaks
it needs hacked and modified to suit
yourself
the USB is USBC unfortunately they've
Not Included the two resistors that let
it indicate to Modern intelligent USB
power supply that it should be put now
current so it doesn't uh Supply the 5
volts uh you're gonna have to plug this
into a dumb and charger if you wanted to
charge
there is a decoupling capacitor across
that which is good it's part of the
textbook thing for this there is the
classic one resistor going from that
incoming positive Supply so let's call
this plus 5 volts
I will call this
2.42 4.2 volts because that's actually
what it is and zero volt down here
so the resistor goes from the 5 volt
Supply to two LEDs the red LED is
switched to the zero volt rail by this
chip when it's charging but then it
switches off when it is fully charged so
what actually happens there is that one
is charging the current flows through
this resistor through the red LED that
pulls the voltage down to about two
volts across that which means that the
green LED can't light when the charge is
completed and it turns the red LED off
the voltage goes up higher and then the
green LED can lights very very simple
it's a a one pin two color one resistor
Arrangement very neat there's a 2K
resistor that programs the current
there's the output to the measurable
lithium cell that they'd actually
soldered onto the ends I wonder if this
is a recycled cell I wonder if it's
basically just a
bin re-sleeved just because it you know
it's an end of Life Cell because this
size should have a much higher capacity
but there is loads of options you could
there is space in here
it's kind of optimized for the size of
cell but there's also the position for
putting a rectangular cell in so you
could actually even cut some of the
plastic away and you could stuff this
with as much lithium cell as you could
fit in there loads of potential
there's a decoupled supply for the
microcontroller so it's not affected by
the switching the pulsive modulation of
the the LED which causes a slight
fluctuation so it's a ternal resistor I
measured there is the capacitor in
circuit is roughly 5.5 megafar closest
5.6 but that testing circuit that could
be affected by the microcontroller and
this one also tested roughly 100 Nano
which is about right for that but that
again that was in circuit
there's a button pulling to the zero
volt rail here is the transistor I
thought this was going to be a mosfet
it's not it's a standard npn transistor
it's a y1 but it does have the normal
component arrangement for a mosfet 10K
pull down resistor 1K control resistor
and it dropped 1.3 volts and used it was
dropping a higher voltage than these
resistors which is just odd there's a
two resistors too one ohm in series
although the transistor is doing all the
current limiting because it's being
pushed quite hard it go up to about 30
degrees Celsius which isn't dramatic but
it's not ideal
and there's the LEDs uh scope for
hacking aside from upgrading the lithium
cells greatly you could replace this
with an a2shb probably
a suitable mosfet if it's pin compatible
should be pin compatible let me just
check this out
uh get uh yes that would work emitter
and collect that uh gate Dimension
collector gate source and drain that
would work
yes interesting I wonder where my
a2shp's are a big strip of them and I've
lost them but loads of uh potential and
then of course you can change these
resistors if you wish you can increase
the capacity you can make it more
efficient or keep the existing
transistor Arrangement you could cut one
of these resistors off if you wanted it
to last longer or just adjust it to
whatever sort of intends to battery
versus uh lifespan run time you you
wanted
but there we go uh it's actually all
right it's a good starter project if you
will I mean that's quite a nice product
I do like this so probably going back
together again I may retrofit it with a
better self now another option you have
here if you're looking for something
more decorative lower current even you
could replace the filaments but there
you could actually just tack in some of
those uh copper wire LEDs the ones that
are just soldered along cover one you
could just fill it with those just to
create a cluster of little Points of
Light if they do that but the filament
itself looks quite nice and with enough
hacking this could actually be a very
useful camping light is the option of
just recharging it from a suitable five
volt solar panel so uh it's not bad I
quite like it it's a very nice little
device