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Haemogoblin
May 24th, 2011, 01:06 PM
Hi

I'm hoping there are some people on the board who will be able to follow this..

My old Plus finally gave up the ghost and i'm in the process of fixing it. I'm going to begin with replacing C1 with a 10uf 50v not polarized capacitor. Then check the voltage on via the floppy port.

I picked up the replacement cap from the electronics store today, however the replacement part is tiny. It's a 1/3 the size of the original. Cap replacement 10uf 50v (http://www.maplin.co.uk/non-polarised-electrolytic-capacitors-12777) I'm following a PDF guide i downloading. In which is says...

"Whether or not refreshing J1ís solder joints fixes your display problem, take a close look at capacitor C1. Depending on model and production date, it will be either a 3.9 or 4.7mF (microfarad) nonpolar electrolytic capacitor (the value is not terribly critical in this particular case). The top metal should be flat. If it bulges visibly, itís dead; no need to do any further checking at all. Also check for bulging on the bottom, where it touches the PC board (sometimes this is hard because of the massive amounts of hot glue often present). Replace it only with a nonpolar, low loss (low ESR -- thatís effective series resistance) unit rated at 50V or more. Do not replace this capacitor with the same type as the original."

Druid6900
May 24th, 2011, 02:56 PM
OK, what, exactly, is wrong with it? Is it totally dead or just no video?

Haemogoblin
May 24th, 2011, 03:24 PM
Well its began doing the random restarts and then finally died, it doesn't chime, it's simply dead. I'm assuming something has blown, perhaps the fuse or one of the capacitors. As C1 is apparently one of the first things to go, i thought i'd start there.

One of the reasons i posted, was just get a little confirmation on the replacement component i've purchased to replace the cap on C1. As i said earlier, the fact the replacement is less then half the size, concerns me. Wanted an expert opinion on whether i've bought the right part to do the job.

Cheers
James

Druid6900
May 24th, 2011, 06:43 PM
One of the reasons i posted, was just get a little confirmation on the replacement component i've purchased to replace the cap on C1. As i said earlier, the fact the replacement is less then half the size, concerns me. Wanted an expert opinion on whether i've bought the right part to do the job.

Well, from the description, the unit you bought replaces a much larger component, probably due to the fact that it's non-polar and isn't subjected to a massive voltage across it.

It can be smaller because it doesn't need the extra material to resist a high breakdown voltage between the layers.

Haemogoblin
May 25th, 2011, 02:20 AM
Cheers

I was just a little concerned, when the guy handed it over to me at the store. I was like "is that it??" lol as the original is much larger. I scared the thing will explode on me or something.

Cheers
James