Scopemeter 97 repair

From NURDspace
Scopemeter 97 repair
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Participants
Skills Soldering, Electronics, Hackery, Troubleshooting, 1337 Skillz
Status Getting parts
Niche Electronics
Purpose Infra
Tool No
Location Secret Base
Cost dead scopemeter and some capacitors
Tool category Electronics

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Let's document a project for a change :)

What

Found a dead scopemeter 97 on everyone's favorite auction site for a bargain and got it. But it's dead. Now what. Let's fix it :)

Status

It came with the original power supply so that was great. It was missing screw's and someone already had a go at fixing it. However nothing inside seemed to be bodged or fucked up inside so thank you the one trying to fix it for not making it worse :)

Plugging it in and pushing the on button. Nothing. Dead ... Or is it....

When pressing the power buttong I could hear a faint "Squeeeep" sound. This is an indication that part of the switched mode power supply circuitry is powering up, but failing somewhere along the way. Bingo

This also means the keyboard and on/off switching circuitry are still fine. (hopefully)

The appears to be nothing wrong at first glance but closer inspection of the SMD capacitors show discoloration of the solder pads show that that have been leaking. Old SMD capacitors are notorious for leaking and killing electronics.

One evening of nurding over schematic's, partlists, datasheets and a part suppliers site later. We have ordered ourselves some replacement caps.