Re: Gain login access to old CISC AS/400e

Hello Conrad,

Am 26.03.2020 um 01:53 schrieb Conrad Kostecki <ck+midrangel@xxxxxxxxxxx>:

just a current quick update. Unfortunately I have bad news. The AS/400 is starting since today to malfunction. After powered on and initiated IPL, it stopped during IPL and falled back into standby, just like, when you initally power on the AS/400. But worse, you could smell some sort of "fishy" (don't know, how to better describe that in english). I now that smell is typically, when caps or something seems to die in terms of electronic. That smell comes back, when IPL is initiated, but does not, if only powered on, but no IPL started. But for now, I leave the AS/400 offline.

I had the same once on my 150. Apparently one of the mains side caps exploded and thus wasn't available for removing mains ripple. Luckily, there were no other defects.

Replaced both (!) caps: In 115V mains, they're used in a voltage doubler circuit, in 230V main, they're simply put in series (because each one cap has just 200V nominal voltage). To keep that series cirquit balanced, it's important to replace both caps.

Afterwards, the box worked just fine again.

:wq! PoC

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