Courui Big Head - loss of brightness

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G0OSE
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Courui Big Head - loss of brightness

Hi there, I bought a Courui Big head and all was fine – until I started to play with it.
The first thing I did was replace the thin tailcap wire with a nice thick one – all fine there.
Next I unscrewed the led on it’s base – tried to remove the pcb but its glued in ( I can see the white glue) anyway I decided I should be able to do what I wanted without removing it.
I wanted to just change the led driving wires to 22 guage, which I did all ok – put it back together and it has lost around 60% of it’s brightness, I thought oh well I’ll put it back to how it was originally (thin wires), which I did but it is exactly the same.
Has anyone any idea what I have done – i feel like screaming lol, first real mod first balls up! I was so careful to, I really can’t see what I could have done?
I would be so gratefu if anyone can help me out.

Hopback
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Hi Go0se,

not sure but could a solder bridge have damaged the driver? Or the reflector shorting out briefly on the freshly soldered star and damaging the driver?

If you want a Courui driver, I’ve got one you can have for free Smile

G0OSE
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I have no idea at all – I was very careful.
The thicker wires have touched the back of the reflector as you can see it on the solder (flattening), and the back of the reflector.
Looking at everyone elses mods, they upgraded the wire, so I copied them – surely theirs would have touched too?
If you wouldn’t mind I’d like that driver, I’ll happily pay for it Smile

Hopback
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The driver is worth nowt to me, I couldn’t charge you for it. PM me your address and I will stick it in the post for you monday.

Caleb-v
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That happened to me on a light and it was from a blown resistor. If you look at the resistors they may have a black dot in the middle that would indicate it’s blown. That would happen when it shorted out on the reflector maby? Try bridging the resistor with wire and eliminate any shorts

G0OSE
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You may be right there – it’s hard to see as the board is fixed in and deep, but it looks like the biggest one there is damaged (i cant read the value) looking at others it’s the R200
Update- I did bridge the resistor and it has made a difference but i’m still not sure it is quite as bright as it was, is it safe to leave it bridged?

Gj
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Never hurts to put a bit of Kapton tape on the back of the reflector.

Caleb-v
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When you bridge it you are essentially making it direct drive. The current wil only be restricted by other components and connections. You will lose any low voltage protection. That’s the only real danger I think correct me if I’m wrong.

Hopback
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It has been reported in the other Courui thread that bridging the resistor gives you permanent moonlight when ‘off’ on the electronic switch.

G0OSE
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Morning! Thanks for your inputs!
So basically, don’t let it run too low – check
and the moonlight mode – well I did read that too, but mine doesn’t do it! I didn’t remove the possibly blown r200, but I did literally solder a wire to each end of it (about 15mm long and around 24 awg).
Someone found a ‘selection’ pack of resistors ( afew different ones) at Fastech here I am very happy to solder, but my knowledge of such things like resistors is limited – I don’t suppose someone could tell me which of those packs has the correct R200 resistor in? Then I’ll order a pack and repair my board Smile That said it is glued in well – I’m not trying to remove it at all until my replacement board arrives from my new best friend Beer

Rod911
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Gj wrote:

Never hurts to put a bit of Kapton tape on the back of the reflector.


I do this all the time now instead of using centring rings. When possible, it gets the LED jammed into the reflector as close as possible without having to worry the reflector will short things.