Welcome Guest! To enable all features please Login or Register.

Notification

Icon
Error

Login


Options
View
Go to last post Go to first unread
dem626  
#1 Posted : Friday, March 7, 2014 3:30:30 PM(UTC)
dem626

Rank: Member

Groups: Member
Joined: 3/20/2012(UTC)
Posts: 2
Location: richmond, va

Working on a new BIII stereo build. I adjusted the LCPBS to 15v on both + and - rails but when I hooked up the Legato the R2 resistor on the negative rail of the LCBPS smoked!

I replaced the resistor and the LCPBS is still working.

I assume the problem is with the Legato since the LCBPS works standalone. Does anyone know how I can figure out what is wrong with it? Is there any obvious culprit (besides my craftsmanship!) involved here to focus on? I have reflowed the joints not knowing what else to try and don't see any obvious shorts.

I was thinking about putting two fuses holders between the two boards while troubleshooting, but other than that I don't really have any ideas. If anyone has any ideas, please let me know.
Thanks,
Doug
avr300  
#2 Posted : Friday, March 7, 2014 10:37:28 PM(UTC)
avr300

Rank: Member

Groups: Member
Joined: 6/17/2008(UTC)
Posts: 921
Denmark

Thanks: 1 times
Was thanked: 70 time(s) in 69 post(s)
What's the size of R2? (during time there has been a few values).

It might be 10R if it's an older LCBPS. The current version is using 2R7.

If it's a 10R, try shorting it (just place a wire link under the board)

I don't think there anything wrong with your Legato. It just demands current. A lot of it, especially when running at +-15v. Any series resistance will get hot.

Can you post a picture of the rig?
dem626  
#3 Posted : Sunday, March 9, 2014 5:05:42 PM(UTC)
dem626

Rank: Member

Groups: Member
Joined: 3/20/2012(UTC)
Posts: 2
Location: richmond, va

Thanks avr300 for the info, but as it turns out I left the 2R7 in place on the LCBPS. I discovered, kind of accidently, that there was continuity between ground and negative on the Legato. I went over the board again running my iron between solder joints to make sure there was space between them. Then the continuity problem was cleared up. When I plugged it back up to the LCBPS there was no smoke. Now I have music coming out of the Legato! Wow that made me smile.

I'll post pics eventually. Right now I just have parts connected on a piece of plywood while testing everything. Currently using an RPI/I2S straight to the BIII. Moving on to the Hifiduino next.

Thanks to everyone who posted info, otherwise I couldn't do any of this.
Rss Feed  Atom Feed
Users browsing this topic
GuestUser (3)
Forum Jump  
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.