Sansui AU-101 blown fuse

[MaartenVB]

Hi,

I got a Sansui 110v/220v switchable AU-101 with a blown wired in 2A fuse at the small power supply rail. I put in a new one to check but it blows. All transistors and caps are replaced and it worked fine but after I put a 0.01uf 275v x2 cap behind the power switch it blows. Could this be a problem?

thanks

 

[Hyperion]

but after I put a 0.01uf 275v x2 cap behind the power switch it blows. Could this be a problem?

Take the added capacitors out and check it again? - are you replacing 'original fit' capacitors or adding them for some reason?

BTW 275V isn't nearly enough voltage rating (if that is 275V DC?) for a capacitor in a 220/240V mains circuit - you need at least 600V DC (1000 is better) OR, AC rated capacitors in which case 275V AC rating is enough. Note there are special capacitors with an 'X' or 'Y' rating for use in mains circuitry - this is what you should be using.

 

[MaartenVB]

thanks,

I put in a 275 VAC x2 safety cap (0.01uf).
I just replaced all the old caps for new ones. It ran fine with them for weeks, I'll check the caps agian
edit: the x2 cap is a ECQ-U2A103MLA

 

[MaartenVB]

In the service manual there is 1 rectifier diode D001 (10 DC 1). I got 2 on the board and its says IR4G. 1 of them is faulty. Anyone know a replacement?

 

[Hyperion]

I got 2 on the board and its says IR4G

I can't find any reference to 'IR4G' online, guessing that's the problem you found.

I just realised the diode type number is actually '4G' made by IR = International Rectifier.

An alternative used in the AU-101 is the 10DC-1 (a dual rectifier) which seems like it might be 100V @ 1 Amp, however the fuses are 2 Amp.

A possible replacement might be a 1N4002, (100V, 1 Amp) but if it were me I would go with a pair of 1N5392 = 100V 1.5A (or 1N5393) or any in that series.

 

[MaartenVB]

Thanks! I only have a couple of UF4004GP which is 400v 1A. would this work?

 

[Hyperion]

Thanks! I only have a couple of UF4004GP which is 400v 1A. would this work?

It would probably be OK, but I have a suspicion that the '4G' diodes might be rated for higher current than the 1N4004's

 

[MaartenVB]

Ok i ordered some 1.5A diodes just in case

 

[playittwice]

Man I wish you the best getting this amp going! If you haven't heard one of these yet, I think you'll be pleasantly surprised. I have its bigger brother, the 505, and its a very nice sounding piece.
Good luck!