Hi Mark
I posted some pictures with the differents configuration, could you please advice which is the correct one?
Thanks again!
I posted some pictures with the differents configuration, could you please advice which is the correct one?
Thanks again!
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Photo's 4 to 9 show the correct way to connect the transformers for 26-0-26 Volt.
Don't use the green/yellow wire to connect the transformers secondaries to the chassis (mains earth). Connect the 4 transformer leads to the inputs of the PSU with 2 of the wires connected to the PSU ground. Connect a wire between the PSU output ground and chassis.
Don't use the green/yellow wire to connect the transformers secondaries to the chassis (mains earth). Connect the 4 transformer leads to the inputs of the PSU with 2 of the wires connected to the PSU ground. Connect a wire between the PSU output ground and chassis.
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Hi Mark,
I tried the configuration but when I connected to the chip I heard a sparkling.
I dismount and reset in the previous configuration but now one of the two channels is not working anymore and on the audio out I can see 12-13 volt, what can I do to understand which component is failing?
Thanks
I tried the configuration but when I connected to the chip I heard a sparkling.
I dismount and reset in the previous configuration but now one of the two channels is not working anymore and on the audio out I can see 12-13 volt, what can I do to understand which component is failing?
Thanks
There are several suspect solder joints, try re-soldering.
I have had the feedback loop fail a few times and it did not damage the LM3886, it does damage/destroy the speaker though.
Good time to build a http://www.diyaudio.com/forums/power-supplies/167579-light-bulb-tester.html#post2200138.
I have had the feedback loop fail a few times and it did not damage the LM3886, it does damage/destroy the speaker though.
Good time to build a http://www.diyaudio.com/forums/power-supplies/167579-light-bulb-tester.html#post2200138.
Attachments
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these comments will not sort your problem.
That big input? capacitor has some odd marking that I don't understand.
It states:
4µ7K100 X2
That reads to me as:
4µ7 = 4µ7F
K = ±10% tolerance
100 = maximum voltage of 100Vdc
X2 = X rated capacitor for use on mains supplies upto 250Vac and usually rated for 275Vac maximum.
The 100 and the X2 contradict each other which makes me suspicious of what the capacitor is purported to be.
Why have you used a 4u7F input capacitor?
There does not appear to be any HF decoupling for the supply rails. Is it installed on the underside?
That big input? capacitor has some odd marking that I don't understand.
It states:
4µ7K100 X2
That reads to me as:
4µ7 = 4µ7F
K = ±10% tolerance
100 = maximum voltage of 100Vdc
X2 = X rated capacitor for use on mains supplies upto 250Vac and usually rated for 275Vac maximum.
The 100 and the X2 contradict each other which makes me suspicious of what the capacitor is purported to be.
Why have you used a 4u7F input capacitor?
There does not appear to be any HF decoupling for the supply rails. Is it installed on the underside?
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I getting crazy, yesterday while I was doing additional tests on the LM3886 suddenly it burnt itself..... I don't know if does it make sense to replace only the chip or to throw everything away and reorder the kit....
I am just thinking if it would be possible that all test weakened the chips and this is the reason to make it burn... but I am not really sure also if the rectifier is working properly...... I am getting in confusion....
I am just thinking if it would be possible that all test weakened the chips and this is the reason to make it burn... but I am not really sure also if the rectifier is working properly...... I am getting in confusion....
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- LM3886 works in a few seconds then it shut off.