On Sunday, November 27, 2016 at 3:41:14 PM UTC-5, Michael J. Mahon wrote:
> D Finnigan <dog...@macgui.com> wrote:
> > In a tragic twist of irony, I powered on my Apple II Plus last evening after
> > a year in storage to test it. Didn't have it on much longer than 25 minutes
> > or so when I heard a sickening noise. A crinkling sound, then a column of
> > acrid smoke rose from the rear (switch end) of the power supply. Like a
> > flash I flipped off the switch and pulled the plug, but I fear the damage is
> > done.
> >
> > If you've read up to chapter 2 of The New Apple II User's Guide, or have
> > looked at the back cover of that book, then you have seen this Apple II
> > Plus, a fairly early model from spring 1979. And what I presume is its
> > original power supply is now up in smoke!
> >
> > Now I'm asking the Apple II community if someone can provide a replacement
> > supply, can fix this one, or can offer instructions for me to fix it.
> >
> > I'll be highly appreciative.
> Be of good cheer. ;-)
>
> The odds are excellent that the only failure is the mains filter capacitor,
> an "X1" type, that is easily replaced. (In fact, you can even run without
> it!)
>
> The downside, as you've observed, is the strong, disgusting odor, but that
> will slowly dissipate.
>
> You may also have blown the nearby fuse, also easily replaced.
>
> If the X1 capacitor (a box-like affair, about an inch square and 1/4"
> thick, mounted on its edge) isn't obviously blown, the problem may be
> elsewhere, but first, the most likely thing...
> --
> -michael - NadaNet 3.1 and AppleCrate II: http://michaeljmahon.com

Hey Micheal!,

I am really confused where to find the x1 filter capacitor

newt <drpooh16@icloud.com> wrote:
> On Sunday, November 27, 2016 at 3:41:14 PM UTC-5, Michael J. Mahon wrote:
>> D Finnigan <dog...@macgui.com> wrote:
>>> In a tragic twist of irony, I powered on my Apple II Plus last evening after
>>> a year in storage to test it. Didn't have it on much longer than 25 minutes
>>> or so when I heard a sickening noise. A crinkling sound, then a column of
>>> acrid smoke rose from the rear (switch end) of the power supply. Like a
>>> flash I flipped off the switch and pulled the plug, but I fear the damage is
>>> done.
>>>
>>> If you've read up to chapter 2 of The New Apple II User's Guide, or have
>>> looked at the back cover of that book, then you have seen this Apple II
>>> Plus, a fairly early model from spring 1979. And what I presume is its
>>> original power supply is now up in smoke!
>>>
>>> Now I'm asking the Apple II community if someone can provide a replacement
>>> supply, can fix this one, or can offer instructions for me to fix it.
>>>
>>> I'll be highly appreciative.
>> Be of good cheer. ;-)
>>
>> The odds are excellent that the only failure is the mains filter capacitor,
>> an "X1" type, that is easily replaced. (In fact, you can even run without
>> it!)
>>
>> The downside, as you've observed, is the strong, disgusting odor, but that
>> will slowly dissipate.
>>
>> You may also have blown the nearby fuse, also easily replaced.
>>
>> If the X1 capacitor (a box-like affair, about an inch square and 1/4"
>> thick, mounted on its edge) isn't obviously blown, the problem may be
>> elsewhere, but first, the most likely thing...
>> --
>> -michael - NadaNet 3.1 and AppleCrate II: http://michaeljmahon.com
>
> Hey Micheal!,
>
> I am really confused where to find the x1 filter capacitor
>

“X1” is a capacitor type designation, not a value. It means that the
capacitor is certified for direct connection across the AC line. They are
typically polypropylene dielectric capacitors which are “self-healing” in
the event of breakdown caused by voltage spikes well in excess of their
voltage rating.

You are looking for a capacitor in the 0.1 to 1.0 uF range with a voltage
rating of, typically, 250 VAC. They are pretty widely available and are
inexpensive.

I often see them advertised by the surplus store Electronic Goldmine,
usually in lots of five or ten for a couple of dollars. They are also
available from any electronic parts supplier.

If you’re having trouble locating a supplier, Google “X1 capacitor” and you
should get lots of possibilities.

The exact capacitance value is not too important, since its only purpose is
to attenuate fast spikes coming from the line and filter noise generated by
the power supply going back to the line. Physical fit is the other
important consideration.

I expect you’ll not have much trouble finding a replacement. Best of luck!

--
-michael - NadaNet 3.1 and AppleCrate II: http://michaeljmahon.com