C1 (3.9µF NP high-frequency horizontal deflection capacitor)
C1 (3.9µF NP high-frequency horizontal deflection capacitor)
WOW! TOO GOOD TO BE TRUE!?
Sounds like you're talking about "C1", the Mac's high-frequency 3.9µF NP horizontal deflection capacitor. Thanks for posting that link; I was just looking for one. At 1/6th the price, that's a great deal! (Hmmm... AllElectronics says I need to add
"Only $74.50 more" to my cart to get free shipping. :D )
You wouldn't happen to know a similarly good source of Classic Mac flyback transformers, would you?
VOLTAGE
By the way, you are right about the datasheet. All Electronics is underselling the part by claiming 225V, but even so, that would still be way more than what Classic Macs came with: 25V for the original Mac and 35V for the SE, both at 85°C.
FREQUENCY
My main concern wasn't the voltage but the
frequency which All Electronics doesn't even mention. The
datasheet has a chart showing max current for all frequencies up to 100kHz, which would be way more than the 22.25kHz frequency it'd be switching as C1. I had been concerned about that because I had been going by advice in
Macintosh Repair and Upgrade Secrets which says,
...the physical size of a replacement capacitor is a good indicator of whether or not it's going to work in the C1 application. [...] The tiny 100-V cap on the right is a firecracker waiting to explode. It's completely unsuitable, even though its ratings (4 mfd 100 V) suggest that it might be OK. Use common sense. Don't rely on ratings.
This looks like a teensy-tiny part, so I would have passed this one up. (You already tested this in your Macintosh, right?) Did you see the note in the datasheet that says,
※Please contact us in case pulse cycle exceed 10,000 times
That sounds to me like Taitsu would rather you buy a different part if you're going to be switching faster than 10kHz. (For example, the
PMS395J 2E which does appear to be rated for 22.5kHz instead of 10kHz, presuming the "F" column in the chart means "Frequency in kHz").
HEAT
My next concern would have been heat. According to that same book, C1 failed often in hot weather resulting in a single vertical line. The SE's 35V @85°C capacitor could handle the heat better than the 25V part but, interestingly, it is simply because the capacitor is larger so it can dissipate a little more heat. The Taitsu capacitor, being tiny might have some difficulty with that, but maybe it won't matter as much given its much higher working temperature rating of 105°C.