Cheap LED lantern upgrade

[concept0]

First LED mod project, need a little advice:

I've got a WeatherX emergency lantern (w/ weather radio) that runs off of 6-C cells. The 5mm LEDs it uses are not very bright and I would like to replace them. Assuming I can get to the board they are mounted on, what has to be done to replace them?

Is this just a straight remove and replace job on the LEDs using a soldering gun? What would be the best LEDs to replace with? I was thinking Nichia GS (2x) LEDs... what would be the best source for these?

Thanks for any advice!

 

[DM51]

I'll move this to the Lanterns sub-forum for you.

 

[Lynx_Arc]

if they are 5mm LEDs it probably would be just a straight swap. If you were to go to GS it would probably be twice as bright as it is now but how many LEDs are in this thing? 6C cells for 5mm LEDs and a radio sounds way overkill to me I would be tempted to try and install a buck circuit and put a cree or 3 in it to really brighten it up.

 

[flashlife]

First LED mod project, need a little advice:

I've got a WeatherX emergency lantern (w/ weather radio) that runs off of 6-C cells. The 5mm LEDs it uses are not very bright and I would like to replace them. Assuming I can get to the board they are mounted on, what has to be done to replace them?

Is this just a straight remove and replace job on the LEDs using a soldering gun? What would be the best LEDs to replace with? I was thinking Nichia GS (2x) LEDs... what would be the best source for these?

Thanks for any advice!

What Lynx said...

But a soldering gun is overkill (in a bad way). Get yourself a cheap Radio Shack iron, 40 watts max, with about a 1/16" to 1/8 wide tip, and some 63/37 tin/lead solder (not the plumbing stuff..it uses an acid core).
http://www.radioshack.com/product/index.jsp?productId=2062730

Personally, I'd just swap the stock 5mms for your brighter Nichias.

 

[concept0]

DM51: Thanks, I didn't know there was a lantern forum. Doesn't seem to get a lot of traffic, though...

Lynx_Arc: It's got two "wings" with 12 LEDs each (http://www.walmart.com/catalog/product.do?product_id=8111439). There's a 4-way switch on each wing (off, 4 LEDs, 8 LEDs, 12 LEDs).

I think it would be better to go with a straight swap. I was hoping that the newest GS LEDs would be more than twice as bright as whatever it uses, because I was under the impression that the new GS LEDs were twice as bright as the old GSs (or is that the DS?). This cheap sucker probably doesn't even have Nichia LEDs at all...

When I compare the lantern on 4-LED setting to my Photon ReX (4x GS) on high, the Photon is blinding while the lantern is basically just a pleasant glow.

flashlife: Maybe I'm using the term too generally. I thought the term "soldering gun" could refer to any soldering iron. Does it only refer to the high temperature gun-shaped ones?

 

[Lynx_Arc]

Ahhh, more information..... 24 LEDs with 2 4way switches? ugh.
I would consider two things:
1)selling this lantern or leaving it as is and buying another high power LED lantern.
2)taking apart the circuitry to see if it can be modified to replace the columns of LEDs with high power LEDS.

I say this because 24 nichias is going to cost you at LEAST $25 to get and you will have to wait for a group buy at that or you will have to pay closer to $30 or more to order less than 100 of them. Nichia GS are brighter but if you use this lantern a LOT they are listed as starting to fade after 1000 hours while the DS are ok to 10k. At $25-$30 or more you can BUY a better lantern or even two on the marketplace when the guy selling them for about $13 plus shipping gets more.

As for the iron term... soldering guns are typically high power irons with large tips 75 watts to 250+ watts and are unsuitable for electronics in general... like trying to put a picture frame together with a sledgehammer IMO.

 

[flashlife]

flashlife: Maybe I'm using the term too generally. I thought the term "soldering gun" could refer to any soldering iron. Does it only refer to the high temperature gun-shaped ones?

OK, Then.
Soldering guns are usually 100-150 watts...way too much for flashlight work...unless you've got a REALLY BIG flashlight.

Weller 100/140 Watt Soldering Gun.

 

[concept0]

Ahhh, more information..... 24 LEDs with 2 4way switches? ugh.
I would consider two things:
1)selling this lantern or leaving it as is and buying another high power LED lantern.
2)taking apart the circuitry to see if it can be modified to replace the columns of LEDs with high power LEDS.

I say this because 24 nichias is going to cost you at LEAST $25 to get and you will have to wait for a group buy at that or you will have to pay closer to $30 or more to order less than 100 of them. Nichia GS are brighter but if you use this lantern a LOT they are listed as starting to fade after 1000 hours while the DS are ok to 10k. At $25-$30 or more you can BUY a better lantern or even two on the marketplace when the guy selling them for about $13 plus shipping gets more.

I would like to keep this lantern. I like the fact that it gets AM/FM/Weather, has an AUX input for my iPod, can internally recharge NiMH batteries and run off of AC input. Oh, and it has a backlit clock.

I don't think the reflector design is going to be good for CREEs. I'm going to take a look into a Nichia group buy, though I have to say that I didn't realize that Nichias were so expensive!

 

[concept0]

OK, Then.
Soldering guns are usually 100-150 watts...way too much for flashlight work...unless you've got a REALLY BIG flashlight.

Weller 100/140 Watt Soldering Gun.

Good to know... It's always better to know what a term means when you use it!

 

[Lynx_Arc]

I would like to keep this lantern. I like the fact that it gets AM/FM/Weather, has an AUX input for my iPod, can internally recharge NiMH batteries and run off of AC input. Oh, and it has a backlit clock.

I don't think the reflector design is going to be good for CREEs. I'm going to take a look into a Nichia group buy, though I have to say that I didn't realize that Nichias were so expensive!

Nichia 5mm LEDs have always been expensive, that is why few lights have them as you can get a bag of 100 of the LEDs in your lantern for less than the price of a dozen nichia GS LEDs. I haven't seen a groupbuy for nichias in a few months I should have got a bunch of them at that time.

wish I could see how that is put together, I could give you my take on it. One thing you could do is try and check the current going to the LEDs, it is possible that they are underdriven and changing the resistors out to overdrive the LEDs slightly would make them considerably brighter. I would NOT recommend the GS if they are set to be driven at more than 20ma as it would shorten their lifetime.

 

[Lynx_Arc]

OK, Then.
Soldering guns are usually 100-150 watts...way too much for flashlight work...unless you've got a REALLY BIG flashlight.

Weller 100/140 Watt Soldering Gun.

I have seen 75 watt guns... they don't make them now and I have a weller 260/200 watt professional version of that one. :naughty:

 

[concept0]

wish I could see how that is put together, I could give you my take on it. One thing you could do is try and check the current going to the LEDs, it is possible that they are underdriven and changing the resistors out to overdrive the LEDs slightly would make them considerably brighter. I would NOT recommend the GS if they are set to be driven at more than 20ma as it would shorten their lifetime.

I'm in the middle of studying for law school exams right now (you can tell because I'm on CPF 24 hours/day), but I'll probably take it apart and do some tests at the end of the month...

As always, thanks for the great advice!

 

[Lynx_Arc]

well I am especially fond of lanterns. I have two torn apart I am trying to decide how to mod and parts I want to use to make a 6v 500ma remote control LED lantern. I have a tiny keychain remote about the size of my big toe that takes 4 AG3 batteries in it. I am just trying to get an idea of light dispersion or find a decent priced LED lantern to put the circuit into.

 

[concept0]

well I am especially fond of lanterns. I have two torn apart I am trying to decide how to mod and parts I want to use to make a 6v 500ma remote control LED lantern. I have a tiny keychain remote about the size of my big toe that takes 4 AG3 batteries in it. I am just trying to get an idea of light dispersion or find a decent priced LED lantern to put the circuit into.

Sounds sweet! :twothumbs

Man, I'd like to learn how to build circuits like that... I really should have paid better attention when my uncle tried to teach me all about electronics when I was like 12 years old. We made all kinds of cool stuff, including a time bomb (with flash cubes for an "explosion), and a numeric keypad for my bedroom door that retracted a solenoid when you entered the correct combination.

Let me know how your project goes!

 

[Lynx_Arc]

I didn't build the circuits.... they would probably cost me over $15 in parts and shipping to build. I bought remote controlled lights for cheap off of ebay to scavenge parts for. I have two 6v incan remote closet lights that cost me $4 each I plan on pulling the electronics out of and throwing the light away. My 12LED lantern I have to bypass a resistor to get more than 180ma out of the circuit but it is enough to run a luxeon at a decent level. The lights use 1ma on standby with the 12led using 4ma so running off nimh they should not need to be recharged for awhile. I may yank the circuit out of the 12 led and make it a CCFL lantern instead and use the guts in a tiny 4AA lantern.
HERE is one of my projects from long ago.... still works great I used it when we had a massive ice storm dec 2007 and over half the city had no power for almost a week.

 

[concept0]

I've got that same POS purple lantern! I can't see the ground in front of me when I walk with it... I'm glad yours made something of itself.

I guess that makes sense that you didn't build the circuit. I thought it was strange that you had decided the output of the power supply BEFORE deciding how to make the lights work with that amount of power... :duh2:

 

[concept0]

Okay!

I measured the amperage going to the LEDs and it was 18ma.

Can I run CREEs off this power source directly? If I'm going to need converters or light engines (not entirely sure what this term means) or something, I think it might be cheaper to get Nichias and just connect them directly.

I'm also worried about heat dissipation of CREEs in the plastic lantern "wings." What do you think?

 

[Lynx_Arc]

I've got that same POS purple lantern! I can't see the ground in front of me when I walk with it... I'm glad yours made something of itself.

I guess that makes sense that you didn't build the circuit. I thought it was strange that you had decided the output of the power supply BEFORE deciding how to make the lights work with that amount of power... :duh2:

not strange, my CCFL requires 300ma at 6V to work while a lux 1 requires less voltage to operate. I have tried hooking both up with an ammeter inline along with disconnecting the leds and checking the current. When you have a circuit inline with a light it usually hampers current flow so unless you know more about the circuit sometimes you just have to either calculate it or stick what you are using inline and testing how it works. At times when I am unsure I would put a variable resistor and crank the resistance down towards none while watching the current rise and when it hit too high I would measure that resistance and perhaps use that to add in the circuit.

 

[Lynx_Arc]

Okay!

I measured the amperage going to the LEDs and it was 18ma.

Can I run CREEs off this power source directly? If I'm going to need converters or light engines (not entirely sure what this term means) or something, I think it might be cheaper to get Nichias and just connect them directly.

I'm also worried about heat dissipation of CREEs in the plastic lantern "wings." What do you think?

It all depends on how things are wired.. IMO to get decent output from a high power LED you need at least 300ma through it but to match 24 LEDs you probably need either one cree driven at 700ma to 1 amp or more or two crees at 300-500ma or more. Your measurement may be on one led or on a string of 2-3 leds and the problem you have is your source is 9v which crees are not designed for they use about 3v-4v about so something has to throttle or regulate the excess voltage. 2 crees in serires may come close to the 9v but may still require resistance or a regulator circuit. Unless you have a good idea about electronics to figure out the power circuit and rewire it you may have to do a lot to implant a few crees... but IMO it would be worth it.

 

[concept0]

It all depends on how things are wired.. IMO to get decent output from a high power LED you need at least 300ma through it but to match 24 LEDs you probably need either one cree driven at 700ma to 1 amp or more or two crees at 300-500ma or more. Your measurement may be on one led or on a string of 2-3 leds and the problem you have is your source is 9v which crees are not designed for they use about 3v-4v about so something has to throttle or regulate the excess voltage. 2 crees in serires may come close to the 9v but may still require resistance or a regulator circuit. Unless you have a good idea about electronics to figure out the power circuit and rewire it you may have to do a lot to implant a few crees... but IMO it would be worth it.

I measured the amperage on the leads to a single LED in a string of 4. I'm thinking that I'm probably going to go the Nichia route, since I would lose my adjustability (by selecting the # of LEDs turned on) if I went to a single CREE on each side. I also think I'll have fewer heat issues with the Nichias.

Do you think that installing the Nichias would be a straight swap? Or do you need more information to make that determination?

Thanks for all the advice, BTW!