So after about an hour of operation my Apple /// power supply blew one film capacitor. There was a previous thread about this but I am a bit confused on the cap in question. Apparently these caps are a common problem. One of my Vulcan II power supplies also burned out a similar film capacitor.
Holy crap does it stink when these things go.
Here are a few pics of the blown cap in the Apple ///;
On 8 Nov, 04:46, "atfphotogra...@gmail.com" <atfphotogra...@gmail.com> wrote:
> Hello, > I'm also confused as to the settings on the caps? What does the > 40/085/56 mean?
The only important things are:
Capacitance (0,22uF) and tolerance (I can't see it) Working voltage (250V) Polarized or not (nonpolarized) Distance between the two pin (you had to put in it the PCB)
I think you can find this kind of capacitor from a TV repair.
atfphotogra...@gmail.com wrote: > Anyone have a good place to get the replacement cap for the 0.22 uF?
They're not hard to find, any place selling capacitors should have them. They're mains EMI filter caps, and try not to get any residue on your fingers - they'll stink for days. Oil and paper - and they have been known to occasionally catch fire when they go. I just replaced two in the last few weeks myself, one from a Sord M23 and another from an Apple IIe. I bought them from Dick Smith Electronics here in Australia. IIRC, about AUD$2 each.
>> I'm also confused as to the settings on the caps? What does the >> 40/085/56 mean?
> The only important things are:
> Capacitance (0,22uF) and tolerance (I can't see it) > Working voltage (250V) > Polarized or not (nonpolarized) > Distance between the two pin (you had to put in it the PCB)
> I think you can find this kind of capacitor from a TV repair.
Actually, the capacitance is not at all critical (though if it is too high, it will lower the effective rating of any fuse because of additional reactive current). A 0.1uF replacement for a 0.22uF capacitor will work fine.
The highest working voltage you can find (that is at least as large as the original rating) and will still fit is the best bet. These caps are directly across the AC line, and see any spikes on the line.
All non-electrolytic capacitors are nonpolarized, so no trouble there.
If a replacement will physically fit (not touching anything that gets hot), it will work. You can always bend the leads a bit to get the spacing right. (Use needlenose pliers to avoid high bending stresses.)
The critical thing about any replacement is that it be X2 rated, as the one you show is. These capacitors are designed to sit across the AC line. They are "self-healing" in the event of minor shorts (for most of their life), and so are safe in this application. The downside is that their dielectric impregnant is really smelly. ;-)
- my IIe PSU: http://www.brutal-deluxe.fr/public/CAP_IIE_PSU.JPG Remember the blinking LED on the motherboard! I was wondering whether this could be due to the capacitor, they are all full of "craquelures", oh! a French word.
> - my IIe PSU: http://www.brutal-deluxe.fr/public/CAP_IIE_PSU.JPG > Remember the blinking LED on the motherboard! I was wondering whether > this could be due to the capacitor, they are all full of > "craquelures", oh! a French word.
Don't know about the blinking LED (very improbable), but these are both examples of "X2" capacitors. Replacing them as described earlier should fix any problems related to them (except the residual odor ;-).
> > - my IIe PSU:http://www.brutal-deluxe.fr/public/CAP_IIE_PSU.JPG > > Remember the blinking LED on the motherboard! I was wondering whether > > this could be due to the capacitor, they are all full of > > "craquelures", oh! a French word.
> Don't know about the blinking LED (very improbable), but these are both > examples of "X2" capacitors. Replacing them as described earlier should > fix any problems related to them (except the residual odor ;-).
Sweet! I'll replace the caps tonight and see how it responds.
They sure do stink when they burn. WOW. Right up there with the smell of burnt hair.
I'm thinking of drilling a few holes in an open section of the power supply base on the Apple /// and installing a small 5v or 12v fan that would push the air out the bottom. It just seems that the internals would get so hot without some active cooling. I read the article claiming that the design takes care of the heat properly but it still seems to be quite warm in there.
Toinet wrote: > On 8 nov, 22:32, "Michael J. Mahon" <mjma...@aol.com> wrote: >> Toinet wrote: >>> On 8 nov, 04:46, "atfphotogra...@gmail.com" <atfphotogra...@gmail.com> >>> wrote: >>>> Hello, >>>> I'm also confused as to the settings on the caps? What does the >>>> 40/085/56 mean? >>> I'd like to help you but I can't. >>> I would to share two pictures: >>> - my IIc dead capacitor:http://www.brutal-deluxe.fr/public/CAP_IIC_MONITOR.JPG >>> - my IIe PSU:http://www.brutal-deluxe.fr/public/CAP_IIE_PSU.JPG >>> Remember the blinking LED on the motherboard! I was wondering whether >>> this could be due to the capacitor, they are all full of >>> "craquelures", oh! a French word. >> Don't know about the blinking LED (very improbable), but these are both >> examples of "X2" capacitors. Replacing them as described earlier should >> fix any problems related to them (except the residual odor ;-).
I didn't mean that the blinking itself is improbable (though it is quite unusual!), but that the failed line filter capacitor would not cause the LED to blink.
I can't view your video as I'm writing this, since the computer must be restarted to complete the Quicktime upgrade, but it sounds like a case of the power supply being *just barely* overloaded, so that it goes into shutdown after a short time, then attempts to restart and repeats this cycle endlessly.
Most likely culprits are the electrolytic capacitors just after the bridge rectifier--the only big electrolytics on the line side of the supply. When they age, they become less effective due to both a loss of capacitance and an increase in equivalent series resistance. This erodes the supply's margin until it usually just stops working. Yours is a special case, where it is working for a short time, to blink the LED, then shuts down.
I was working with the supply and went to turn it off. However I hadn't screwed down the supply on the original base, bumped it and shorted it out causing quite a spark and a bit of electrocution.
Sigh..
The fuse blew and one transistor blew its top off. A D467 C 2C 1.
Visually I don't see any other damage but I suppose it will all be tested again if I can find a replacement for the transistor.
I tried the code at Digikey and Jameco with no luck. Any suggestions for somewhere in the U.S.?
> I was working with the supply and went to turn it off. However I > hadn't screwed down the supply on the original base, bumped it and > shorted it out causing quite a spark and a bit of electrocution.
> Sigh..
> The fuse blew and one transistor blew its top off. A D467 C 2C 1.
> Visually I don't see any other damage but I suppose it will all be > tested again if I can find a replacement for the transistor.
> I tried the code at Digikey and Jameco with no luck. Any suggestions > for somewhere in the U.S.?
> I think this Apple /// and I are cursed.
> Thanks!
> ATF
And it looks like on the Apple /// Power Supply schematic that it's transistor Q1 which reads MJ8503.
> I was working with the supply and went to turn it off. However I > hadn't screwed down the supply on the original base, bumped it and > shorted it out causing quite a spark and a bit of electrocution.
> Sigh..
> The fuse blew and one transistor blew its top off. A D467 C 2C 1.
> Visually I don't see any other damage but I suppose it will all be > tested again if I can find a replacement for the transistor.
> I tried the code at Digikey and Jameco with no luck. Any suggestions > for somewhere in the U.S.?
> I think this Apple /// and I are cursed.
> Thanks!
> ATF
D467 is most likely a 2SD467 as is the naming convention for 2S series transistors
There is 2sd467 x 2 pieces on ebay at the moment for $1.78
> > I was working with the supply and went to turn it off. However I > > hadn't screwed down the supply on the original base, bumped it and > > shorted it out causing quite a spark and a bit of electrocution.
> > Sigh..
> > The fuse blew and one transistor blew its top off. A D467 C 2C 1.
> > Visually I don't see any other damage but I suppose it will all be > > tested again if I can find a replacement for the transistor.
> > I tried the code at Digikey and Jameco with no luck. Any suggestions > > for somewhere in the U.S.?
> > I think this Apple /// and I are cursed.
> > Thanks!
> > ATF
> D467 is most likely a 2SD467 as is the naming convention for 2S series > transistors
> There is 2sd467 x 2 pieces on ebay at the moment for $1.78
> Geoff
Heya!
Thanks for info! I almost missed your message. I'll go see what I can find there.
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