Link audio SL4k-e01 smoking when turned on! Need help

[Esppse]

I am building 2 of these. The first one I turned on, I saw smoke come out. I immediately shut down the rack.

SL4K-E01 | Link Audio Design

Features:Jensen Input Transformator JT-115K-EPCGain - 16-68 dB Gain Stepped recallable with Grayhill Switch48V - For Phantom Power MicrophonesPol - Switches the Polarity of the InputPad - Enables - 20dB Pad at the InputLow-Cut filter - 10-250 Hz (24dB/oct)High-Cut filter - 3.5-20 kHz...

www.linkaudiodesign.de

I found the burned area, it is this 5532 chip, pin7.

I am not familiar with routine troubleshooting, I have only followed kit instructions and built many preamps successfully.

What should I do here?

 

[Esppse]

I thought I there was a short on the chassis, so I tried turning it on, a different 5532 blew.

 

[Esppse]

The voltages coming in were both proper at +15 and -15.

 

[Brian Roth]

You mentioned 5532, but the pix also show some 5534 opamps. They are NOT interchangeable.

Bri

 

[Esppse]

Omg.... thanks for the info. I thought they were all the same 5532s. There are 3 5532s, and 4 5534. Looking at some pictures before i plucked them off the sockets, i have mixed up nearly all on the board. This is I'm assuming why they blew... should I replace them all or just the 2 that smoked?

 

[Brian Roth]

Look at the spec sheets for the two opamps and you'll see the BIG differences in the pinouts! <g>

I think you'll probably be OK just replacing the smoked opamps...and the related carnage on the PCB (sockets in particular). But without seeing the entire circuit diagram, it is *possible* there could be some collateral damage elsewhere.

Bri

 

[Esppse]

Look at the spec sheets for the two opamps and you'll see the BIG differences in the pinouts! <g>

I think you'll probably be OK just replacing the smoked opamps...and the related carnage on the PCB (sockets in particular). But without seeing the entire circuit diagram, it is *possible* there could be some collateral damage elsewhere.

Bri

Here is the schematic at the end of the PDF.

SLPREGUIDE4KE01.pdf

SL4K-E01 Introduction. TABLE OF CONTENTS. Let me Introduce this nice Preamp in the Style of a British Console Preamp. I have designed this familiar Preamp in 500 API compatible Format. It works in 500 VPR or 51X Lunchboxes on the +16V and -16V rails. I mainly used the schematic of the 4000E-E01...

www.docdroid.net

Ill purchase enough chips to replace all the 5532 and 5534s. Is it likely the TL072, LM339, and THAT1646, and electrolytics are ok? These were all oriented correctly. Would the 5532s/5534 have any destructive effect on those other chips?

The LM339s are just for LED control I think. Its the THAT1646 thats a little pricier to replace.

 

[Brian Roth]

I didn't "drill down" through the schemos, but I suspect the only casualties would be opamp misplatements....5532 in 5534 sockets and vice versa. That error will most likely only result in smoked opamps (and sockets) in those positions.

No harm to have the other chips in inventory...they can be used in future projects! <g>

Bri

 

[Khron]

There's a (good) reason why different components have different part numbers...

 

[Esppse]

thanks guys, it was a late night, idiotic mistake on my part... should've had more coffee in me heh.

 

[andYz00m]

Ive done this before early in my DIY adventures. Was doing a gar2520 and didnt realize there were different part numbers for the identical looking TO126 packages.

Havent smoked many parts since!

The lesson here is to mind your BOM and schematic!