PowerBook Duo Power Brick

[mitchW]

A friend got me a dead Duo Power Brick, it is completly dead and something shakes inside. Model: M7783

So I want to get it open, but with as least damage as possible.

Like something as I did with the PB 170 PSU last week.

Perhaps anyone already done that?

 

[mitchW]

I used the vise method and it worked. I was able to get it open without any visible marks

The brick is now repaired, as the only problem was the input filter choke that had detached and was shaking inside.

I resoldered it and now it works a treat. Also, there are only two electrolytics inside and both of them are Nichicons, so I belive that they won't need much of recaps in the years to come.

 

[techknight]

all fluid filled caps need changed regardless of brand, anything of that age will eventually deteriorate and start leaking. 

Food for thought: I was recapping a 57 chevy radio, and had a brand new sprauge electrolytic pop is its seal and start leaking. NEW... 

 

[mitchW]

I agree completely. Also I know that some brands are more prone to leakage, such as dreaded ELNAs, but I have yet to see a Nichicon to leak. But anything is possible, I also had a new Sanyo cap a few years ago that just bulged after few seconds.

A month ago I got an old tube radio from 1949 which saw almost no use since the 1955 or so, since all of the components were original and in almost brand new condition. After giving an hour or so for the electrolytics to revive, the radio played well. Actually that well and without any hum, that I decided to leave it all-original for now. I only needed to replace one tar sealed paper capacitor which got hot after few minutes and started to leak tar, others were perfectly fine. So sometimes even after 65 years, the capacitors work fine

 

[techknight]

Yea, and youll see cases of that. Radios are far less susceptible to performance loss from leaky caps. They tend to still work ok even though the caps are shot. 

Tube TVs from the 40s/50s on the other hand, are super sensitive to failing capacitors, especially in the scan circuitry.