Challenge of Repairing vs Trashing
Robert Macy
long. During use on a cold night [40F], it suddenly started
flickering, rather than constantly on. After putting in a new battery,
the same.
Now no matter where even warm office, LED flashlight flickers.
Rate 'appears' to be 8-12/sec with a 70-30/80-20 ON cycle.
Any ideas if it's possible to fix?
Dave M
Therese things are so simple, it's almost embarrassing to ask how to fix
them. Temperature isn't the cause of the problem.
Most likely the on-off switch has pitted contacts. Disassemble the switch
and burnish of file the contacts until the pitting is gone.
Another possibility is that the switch contacts have lost "springiness" and
are barely making contact. Dissasemble the switch and bend them until there
is sufficient force to make firm contact.
If there is no switch (the head and the tube are screwed together to turn
the flashlight on), disassemble the flashlight and clean the dirt or other
stuff that's keeping the pieces from making good contact.
Last, see if the button of solder in the head that contacts the battery, has
taken a depression so that it's not making contact with the battery. If so,
put another good blob of solder on it to make vetter contact.
--
David
dgminala at mediacombb dot net
nesesu
Not so sure about that. I have noticed that my cheap 3 LED flashlight
puts out a moderate RFI when on. Presumably there is a switcher of
some sort that ups the 1.4V from a single AA cell to run the 3 LEDs.
If the OP's one has asimilar switcher, it could have failed in the
cold [poor Pb free solder joint?] and remained faulty when warmed back
up again.
Neil S.
Arfa Daily
"nesesu" <neil_su...@telus.net> wrote in message
news:9d55d6fb-31b4-45de...@k3g2000prl.googlegroups.com...
That would be my thoughts, too. These flashlights are often not quite as
simple as the other poster seems to believe, and it's common to have an
inverter chip built in which, in conjunction with a small external choke,
produces the required voltage at a constant current, to run the LED(s) until
the battery or single cell has reached way below where it would normally
power anything, let alone one or more white LEDs. There are many examples of
how this all works on the 'net. A couple of years ago, Elektor magazine gave
away a little board with one of these ICs and a choke on it, free on the
front of every copy, for readers to play with. I still have mine connected
to a white LED set in the end of an old ball pen tube to use as a light
'probe' when looking for problems deep in CD or tape mechanisms where the
normal bench light won't reach. It runs from a single NiCd cell and remains
at full brightness until the cell just falls over and dies.
Just an additional thought. The problem could also be the LED itself. I have
seen them go intermittent, and if this one is being pulse driven from an IC,
then it might well be that a faulty LED would flicker as the chip tries to
keep it supplied with a constant pulse current.
Arfa
N_Cook
news:sibtp.35070$KZ7....@newsfe08.ams2...
I like the inadvertent buit-in charge meter of multi-LED torch lamps where
they are all in parallel (plus a bit of pcb trace drop). You can tell the
state of battery charge as one or more fail to illuminate, more "failing"
with less charge/voltage .
Wild_Bill
upgrade kits, which extend the battery life of 2 alkaline AA cells to about
20 hours, driving 3 high brightness (not high power) white LEDs.
The circuit board is only about 15mm in diameter, smaller than a dime/US 10
cent piece, populated with components on both sides.
http://www.niteize.com/collections/flashlights/products/led-upgrade-kits
I've found these to be very reliable and worthwhile, although they don't
"throw" much light.. which is common with many LED devices without
exceptionally good reflectors and/or lenses.
--
Cheers,
WB
.............
"Arfa Daily" <arfa....@ntlworld.com> wrote in message
news:sibtp.35070$KZ7....@newsfe08.ams2...
>
>
Wild_Bill
indicators or another compact product that would work well with rechargeable
battery packs of 6 to 12V with a push-to-test button.
--
Cheers,
WB
.............
"N_Cook" <div...@tcp.co.uk> wrote in message
news:ip3jtr$isb$1...@dont-email.me...
Robert Macy
> There are only a few components on the inverter-type board for the Nite-Ize
> upgrade kits, which extend the battery life of 2 alkaline AA cells to about
> 20 hours, driving 3 high brightness (not high power) white LEDs.
> The circuit board is only about 15mm in diameter, smaller than a dime/US 10
> cent piece, populated with components on both sides.
>
> http://www.niteize.com/collections/flashlights/products/led-upgrade-kits
>
> I've found these to be very reliable and worthwhile, although they don't
> "throw" much light.. which is common with many LED devices without
> exceptionally good reflectors and/or lenses.
>
> --
> Cheers,
> WB
> .............
>
>
> news:sibtp.35070$KZ7....@newsfe08.ams2...
>
>
>
>
>
> > That would be my thoughts, too. These flashlights are often not quite as
> > simple as the other poster seems to believe, and it's common to have an
> > inverter chip built in which, in conjunction with a small external choke,
> > produces the required voltage at a constant current, to run the LED(s)
> > until the battery or single cell has reached way below where it would
> > normally power anything, let alone one or more white LEDs. There are many
> > examples of how this all works on the 'net. A couple of years ago, Elektor
> > magazine gave away a little board with one of these ICs and a choke on it,
> > free on the front of every copy, for readers to play with. I still have
> > mine connected to a white LED set in the end of an old ball pen tube to
> > use as a light 'probe' when looking for problems deep in CD or tape
> > mechanisms where the normal bench light won't reach. It runs from a single
> > NiCd cell and remains at full brightness until the cell just falls over
> > and dies.
>
> > Just an additional thought. The problem could also be the LED itself. I
> > have seen them go intermittent, and if this one is being pulse driven from
> > an IC, then it might well be that a faulty LED would flicker as the chip
> > tries to keep it supplied with a constant pulse current.
>
>
> - Show quoted text -
Interesting. This torch is a 'fat' mag-like lite and has six LED's
with the small 'dime' size PCB and a 3 battery pack plastic
assembly.
Closer examination shows that 3 LED's stay lit, but the others are
OFF, except one or two [of the three on one side] flicker as though
trying to come ON. Flicker rate is more like ON for 20 OFF for 80.
Eye retention gives the impression that the LED(s) is on longer.
Earlier comments about connection are interesting in that unscrewing
the front end with the LED assembly - the LED's pretty much stay lit.
BUT! even the slightest unscrewing the tail end [where switch is
located] causes LED's to either go out or substantially change flicker
patterns.
Regards,
Wild_Bill
anything but reliable.
I generally take most things apart to see the (lack of) quality of
work/production methods.
One package of extremely low cost 3-AAA cell F-Ls were made to very low
quality standards.. the LED leads were just twisted together to form the (+)
battery contact, and the (-) leads-to-case were just jammed between the
plastic "reflector" and case.
Apparently, these were all hand assembled, and had no soldered connections
in them.
In general, the heavier the case and the more machining that's required to
make the case parts, the better the quality of production, as far as I've
seen.
Some of the better quality 1W single LED models ($4-8) that I use regularly
have been very reliable.
While I have them apart, I'll apply a little DeoxIT paste to contacts, seals
and threads.
--
Cheers,
WB
.............
"Robert Macy" <ma...@california.com> wrote in message
news:a8f73527-5ba6-41af...@hd10g2000vbb.googlegroups.com...
hrho...@att.net
> There are some very poorly made LED flashlights around, and some of them are
> anything but reliable.
>
> I generally take most things apart to see the (lack of) quality of
> work/production methods.
> One package of extremely low cost 3-AAA cell F-Ls were made to very low
> quality standards.. the LED leads were just twisted together to form the (+)
> battery contact, and the (-) leads-to-case were just jammed between the
> plastic "reflector" and case.
> Apparently, these were all hand assembled, and had no soldered connections
> in them.
>
> In general, the heavier the case and the more machining that's required to
> make the case parts, the better the quality of production, as far as I've
> seen.
>
> Some of the better quality 1W single LED models ($4-8) that I use regularly
> have been very reliable.
>
> While I have them apart, I'll apply a little DeoxIT paste to contacts, seals
> and threads.
>
> --
> Cheers,
> WB
> .............
>
>
> news:a8f73527-5ba6-41af...@hd10g2000vbb.googlegroups.com...
>
> Interesting. This torch is a 'fat' mag-like lite and has six LED's
> with the small 'dime' size PCB and a 3 battery pack plastic
> assembly.
>
> Closer examination shows that 3 LED's stay lit, but the others are
> OFF, except one or two [of the three on one side] flicker as though
> trying to come ON. Flicker rate is more like ON for 20 OFF for 80.
> Eye retention gives the impression that the LED(s) is on longer.
>
> Earlier comments about connection are interesting in that unscrewing
> the front end with the LED assembly - the LED's pretty much stay lit.
> BUT! even the slightest unscrewing the tail end [where switch is
> located] causes LED's to either go out or substantially change flicker
> patterns.
>
> Regards,
Is this a Harbor Freight lite, of one very similar? The switch is a
rubber button in the screw-on base, and is marginally usable for 500
pushes.
Michael A. Terrell
You can find several different types of replacment pushbutton
switches and the flexible covers for LED flashlights on
http://www.amazon.com
--
You can't fix stupid. You can't even put a Band-Aid™ on it, because it's
Teflon coated.
Wild_Bill
which came from an eBag seller.. but generally the quality of much of
Harbor-F merchandise.
The switch is in the end cap.. and another characteristic of low quality
units, is the shiney plastic flexible vinyl covers on the switches, not the
softer, flat black more rubbery-like stuff.
The case is 7/8 to 15/16" in diameter, and 3-1/4" length overall.. very thin
tubing without many deep features.
The value may be to salvage the LEDs (since the leads are long and not
soldered) and the battery holder for use in other, better lights.
These cheap units aren't even good gifts, IMO.. probably better as give-away
trinkets but not to friends.
--
Cheers,
WB
.............
<hrho...@att.net> wrote in message
news:c50578f0-234d-4469...@m13g2000yqb.googlegroups.com...
On Apr 26, 2:13 pm, "Wild_Bill" <wb_wildb...@XSPAMyahoo.com> wrote:
> There are some very poorly made LED flashlights around, and some of them
> are
> anything but reliable.
>
> I generally take most things apart to see the (lack of) quality of
> work/production methods.
> One package of extremely low cost 3-AAA cell F-Ls were made to very low
> quality standards.. the LED leads were just twisted together to form the
> (+)
> battery contact, and the (-) leads-to-case were just jammed between the
> plastic "reflector" and case.
> Apparently, these were all hand assembled, and had no soldered connections
> in them.
>
>
Is this a Harbor Freight lite, of one very similar? The switch is a