Please justify recapping?

[rikbliz]

(deleted)

[cosmiq]

Originally Posted by ajk

@cosmiq

I think AmigaKit offers or at least has offered a recapping service. It's probably the only company that does it, but there are lots of us users who can also help. I'll be happy to have a look if there isn't anyone closer by.

I already found someone who is willing to help. But still - Much thanks for the offer.

[amigakit.com]

Of course we also do track repair as well as Capacitor Replacement and IC replacement.

[Stedy]

If it ain't broke and is in regular use, don't fix it.

If your Amiga is in constant use or has been used at least once in the last two years and once every two years previously, the risk of failure is low. The occasional power up will supply a reforming charge to the electrolytics, thus prolonging their life. I have 25 year old equipment with electrolytics (designed by myself) that still works fine, it is in constant use.

If the Amiga has been in storage for a long time, greater than 2 years, do some checks. An ESR meter can measure the ESR of all capacitors installed, on my A1200, it was 0.050 ohms on the +5V supply but can not detect a high ESR capacitor on the supply. It can check the audio capacitors as they are in series and are more problematic (have had to replace 2 audio caps to date).

If the Amiga has been 'found' again, dragged out of an attic, found at a car boot sale or thrift/charity shop, be wary. It is at higher risk. I apply a soldering iron to the caps, reheat the joint, if a fishy smell escapes, it is suspect.

I use the Peak Electronics LCR and ESR meters for my tests. They will do some measurements in circuit but like all meters, have limitations. The Keysight/Agilent U1733C is great, it also measures dissipation factor (DF) a better means to identify defective capacitors. It's not cheap though. You need to understand some of the complex maths involved with capacitors to understand this http://conradhoffman.com/capchecktut.htm.

Going back to my original comment, If it ain't broke and is in regular use, don't fix it. I've had half a dozen emails from Amiga users, their system was a bit flaky, they re-capped the system, without diagnosing it hoping it would fix their machine. In the process, they wrote off their Amiga. I don't change components without some basic diagnostic first to understand the fault. I work on electronic equipment that costs as much as the average UK house, I can't go round changing parts on the off chance they may fix problems as every re-work/soldering operation has a risk of failure.

Electrolytics are not perfect, no capacitor is but they are not as bad as the Amiga community paint them. A lot of 'bad caps' issues are related to bad design. I acknowledge there was a bad batch many years ago, this does not mean all parts are bad. Common failures I see are capacitors running too hot and at too high a voltage (Netgear SoHo Routers). A 16V capacitor with 15V supply and 1.5V ripple running at 60C will not last too long in the Netgear example, maybe 4000-5000 hours, assuming 85C parts.

I have an A500, A600, A1200 and CD32 with mostly original capacitors. Had to replace two in the A600 on the audio circuit. The A600 had been in storage for 3-4 years when the capacitors failed. I measured the others, they were fine. CD32 has had the two incorrectly fitted PSU capacitors replaced.

I'm an Electronic Engineer, my day job involves developing high reliability systems that fly aircraft, so I'm experienced with component reliability and selection issues

[Arnie]

Originally Posted by stedy

if it ain't broke and is in regular use, don't fix it.

+1

[Jope]

And how. Stedy puts it more eloquently than I could ever hope to.

[toddbailey]

Originally Posted by rikbliz

It's preventative maintenance. If you spend a lot of time and money upgrading/modding your Amiga, you might as well invest a little extra time/money in making sure no leaky caps are going to wreck your system and have it last a good decade or two more.

yes agree 100 % and fyI company's seldom use best quality parts.
My advice is replace before they short and take the system board with it
Hit Mouser or Digikey, find caps rated at 105c and 8000 hrs+ life span.

My moto is when I repair a customers -fill-in-blank- I don't ever want to see it in my shop ever again. caps are cheap insurance, motherboards, custom chips not so much

[toddbailey]

Originally Posted by stedy

if it ain't broke and is in regular use, don't fix it.

yeah, right, I made that mistake once with a vintage McIntosh amp.
Caps shorted and took out a no longer available and very spendy transformer.
The simple truth is these parts have a finite life span, electrolytic caps (espc the cheap ones) are notorious for failing with little to no warning.
It's cheap insurance, besides it's not overly spendy and a relatively easy task to do.

If you don't want the task, send the job to me, I do good work and don't cost a small fortune