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homestar_kevin
Copper Member
USA
34 Posts |
 Posted - 05/15/2008 : 04:06:33
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So last summer I bought a broken dd-5 for 20 bucks( )
What was wrong with it?
Someone had plugged the wrong power supply into it and fried it
so after cracking it open and with the help of many people here I pulled a resistor that was right next to the power jack that was burnt up.
after I did that the pedal worked perfectly! I was excited and loved it, I never got around to replacing that resistor because I'm dumb, i'm lazy and because I wasn't sure what kind of resistor it was.
fast forward 8 months later, the pedal still worked fine but what I did because again I'm dumb.... I plugged my onespot daisy chain into my whammy's ac adapter( ) so that's 12 ac volts into the dd5 and we're back to it not working
do you guys have any advice where to start?
I think I'm going to go to this mom and pop electronics store by my house that have a great reputation for being good and having lots of knowledge and seeing if they can help me out any but If anyone has a full schematic for it? I've seen some that are incomplete but blehhhh. enough rambling.
what do you guys think? |
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Laurie
Double Platinum Member
Canada
4854 Posts |
Posted - 05/15/2008 : 05:13:24
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quote:
Originally posted by homestar_kevin
So last summer I bought a broken dd-5 for 20 bucks()
What was wrong with it?
Someone had plugged the wrong power supply into it and fried it
so after cracking it open and with the help of many people here I pulled a resistor that was right next to the power jack that was burnt up.
after I did that the pedal worked perfectly! I was excited and loved it, I never got around to replacing that resistor because I'm dumb, i'm lazy and because I wasn't sure what kind of resistor it was.
fast forward 8 months later, the pedal still worked fine but what I did because again I'm dumb.... I plugged my onespot daisy chain into my whammy's ac adapter() so that's 12 ac volts into the dd5 and we're back to it not working
do you guys have any advice where to start?
I think I'm going to go to this mom and pop electronics store by my house that have a great reputation for being good and having lots of knowledge and seeing if they can help me out any but If anyone has a full schematic for it? I've seen some that are incomplete but blehhhh. enough rambling.
what do you guys think?
Post some close-up pics of the area around the resistor that failed, plus around the part labelled "78L05". Also pics of the copper side of the board.
Let's have a look and see what we can see. |
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stinkfoot
Silver Member
Sweden
181 Posts |
Posted - 05/15/2008 : 22:52:38
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My guess is that the 'resistor' you took out actually were the polarity protection diode. It sits across the power input, and its job is to limit the amount of reverse voltage allowed to about 1 volt. Sometimes, when reverse (or AC) voltage is applied, it will fry, shorting the power out completely. This is a good thing, as it stops any further damage being done.
When removing the diode, you took out the short, letting the pedal work again. Of course, now without polarity protection... which is ok until you actually need it  
Indeed, check the 78L05 - it's the voltage regulator for the delay circuit, and if you're lucky it failed before the delay chip did.
/Andreas |
Edited by - stinkfoot on 05/15/2008 22:53:52 |
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homestar_kevin
Copper Member
USA
34 Posts |
Posted - 05/16/2008 : 01:27:19
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hey guys, I just cracked it open and the resistor I removed was labeled D1
I'm going to go take pics right now, Andreas, where is the 78L05 located on the board, do you have any Idea?
Thanks
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Laurie
Double Platinum Member
Canada
4854 Posts |
Posted - 05/16/2008 : 01:29:24
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| D1 will be the protection diode. 78L05 is a "transistor" shaped component - black with 3 legs. |
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homestar_kevin
Copper Member
USA
34 Posts |
Posted - 05/16/2008 : 02:03:02
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lets hope these help |
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Laurie
Double Platinum Member
Canada
4854 Posts |
Posted - 05/16/2008 : 14:01:58
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Hi Kevin! Pics kinda help (nice camera btw) - really need to see more of the board though, plus the solder side of the board.
As stinkfoot mentioned, this will be what happened - "When removing the diode, you took out the short, letting the pedal work again. Of course, now without polarity protection... which is ok until you actually need it".
My guess is that either the 78L05 is gone, or the main processor is gone. If it's the main processor, it's going to be a pain in the bum to fix...
Do you have a multi-meter you can use to check voltages?
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homestar_kevin
Copper Member
USA
34 Posts |
Posted - 05/17/2008 : 04:29:13
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Hey everyone,
I'm going to florida tomorrow until next thursday, So I'll post more pictures from different view points then!
Thanks for the help so far! |
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Topic |
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hmm dd-5 troubles(again)
