[rescue] Sun 3/50 scsi boot string

[John Hudak]

If you are serious about having a serviceable unit,  and minimize the risk
of the PS taking out critical components on the MB (or elsewhere) ust recap
the PS.  ESR caps have come a long way since the late 90s/early 2000's.
IMHO, if any gear has RIFAs that are more than20-25 yo, replace them before
turning it on. No sense screwing around with iffy old components.
J


On Wed, Dec 28, 2022 at 3:14 PM Jerry Weiss via rescue <rescue at sunhelp.org>
wrote:

>
> On 12/28/22 1:35 PM, Dave McGuire wrote:
>
> On 12/28/22 11:42, Kurt Nowak via rescue wrote:
>
> I have not yet taken the PS apart yet, so I haven'tB had a visual
> inspection yet and whether it has RIFAs. Either way,B I'm not going to fire
> it up withoutB my current limitingB dim-bulb tester, Variac and Isolation
> Xformer. Unfortunately the lettering on the PS is starting to disappearB
> and cleaning the input side will most likely erase it all. I think I saw a
> section in the FE manual that has a rough description of it. The unit is at
> another location for storage so I'll have to take sections of it apart to
> move it by myself without breaking my back. Too many other projects going
> on at the moment.
>
>
>   That's a switching power supply; it will not play nice with a Variac!
>
>              -Dave
>
>
> My own method for vintage electronics with switching power supplies is to
> turn on the device for less than one minute, then leave it alone for a 3-5
> multiple of the on-time.  Repeat the process a few times and slowing
> increase the on time.   The concept is to briefly charge the electrolytic
> capacitors, but don't stress them too long. This may give them chance to
> reform their insulating layer and endure longer on-times.  If the capacitor
> has dried out or doesn't survive the initial start-cycles then you are
> SOL.  Use at your own risk.
>
>   Jerry
>
> _______________________________________________
> rescue list - http://sunhelp.org/mailman/listinfo/rescue_sunhelp.org
>
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