Re: Sharp Microwave - no backlight
replacing all 10 was a wise move,
i found that if you replace an led in anything the brightness/colour usually doesnt match the old ones
Sharp Microwave - no backlight
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Re: Sharp Microwave - no backlight
So I found out what the problem was. 1 LED was blown, creating high resistance. Took a long time to desolder the LCD Screen. Got there in the end.
I ended up replacing ALL 10 Green LED's with Bright White LED's. LOL.
Works sweet.
Thanks for all who chipped in to help.Leave a comment:
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Re: Sharp Microwave - no backlight
Kool. Sorry I didn't read properly.Leave a comment:
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Re: Sharp Microwave - no backlight
Im aware of the dangers, but I wont be touching the megnetron. I only need the keypad/lcd pcb. I've opened it before, 2 years ago, but I didnt have time to fully examine it.Leave a comment:
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Re: Sharp Microwave - no backlight
the radiation is in the oven cavity, the only times you need to worry is if you mess with the magnetron or the door seal.
the back of microwaves is not sealed/screenedLeave a comment:
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Re: Sharp Microwave - no backlight
I don't mean the voltage.... i mean the housing... u'll never now if this thing is closed as it was before.... there is radiation inside... thats what i meant to say... take car...Leave a comment:
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Re: Sharp Microwave - no backlight
buy the guy a new oven then.
there are lots of things that fail in microwaves that arent related to the high voltage capacitor.
newer machines may not even have one if they are invertor-driven.Leave a comment:
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Re: Sharp Microwave - no backlight
... sorry folks... never mind... but in my oppinion a microwave oven is dangereous to fix and not worth to fix... take care of what u doin and think about what i said... i would never ever open such a thing... not worth riskin´yours and others health...Leave a comment:
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Re: Sharp Microwave - no backlight
Looks like the supply for the led circuit is around 18 volts, Q1 is the regulator transistor, C4 is the reg. output cap, R4 seems to be 51Ω1W then there is another C10? 47µf/16v so the actual voltage for the leds is likely around 10~12v, the schematic gets blurry when enlarged.
What about Q2 ? It's directly connected to the LED.Leave a comment:
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Re: Sharp Microwave - no backlight
Looks like the supply for the led circuit is around 18 volts, Q1 is the regulator transistor, C4 is the reg. output cap, R4 seems to be 51Ω1W then there is another C10? 47µf/16v so the actual voltage for the leds is likely around 10~12v, the schematic gets blurry when enlarged.
Yes I had that issue with blurriness too.Leave a comment:
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Re: Sharp Microwave - no backlight
Looks like the supply for the led circuit is around 18 volts, Q1 is the regulator transistor, C4 is the reg. output cap, R4 seems to be 51Ω1W then there is another C10? 47µf/16v so the actual voltage for the leds is likely around 10~12v, the schematic gets blurry when enlarged.Leave a comment:
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Re: Sharp Microwave - no backlight
Will update this post after some results.
Thank you guys.Leave a comment:
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Re: Sharp Microwave - no backlight
well if you can get to the transistor you can test that with a meter
10 leds in series is gonna need 20-30v so thats what needs to be seenLeave a comment:
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Re: Sharp Microwave - no backlight
no, but try reading the voltage across each led instead of just blindly changing stuff.
did you meter the transistor?Leave a comment:
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Re: Sharp Microwave - no backlight
Any idea what the tranny part number is, or equivalent?Leave a comment:
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Channel: Troubleshooting Computer Displays
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