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Do I need to replace my flyback?


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Hi everyone,

 

I'm in the process of recapping the motherboard and analog board of my SE/30 and I've noticed that the "bracket" around the flyback is broken . I read somewhere that you can spot a bad flyback by running the computer in a completely dark room to see if any light or arcing can be seen from the flyback. I don't see anything when my SE/30 is running and all the lights are off. I've linked a couple pictures below, the first one is the computer running and the lights off (sorry for the blurriness but this was taken in complete darkness), the second is the computer off and the lights on, you can see the broken "bracket" in this much clearer picture.

 

I'm looking for any advice/thoughts on replacing this flyback, My machine is running fine although the sound is very very faint and sometimes the video goes jittery, but I suspect/hope I can resolve these issues by recapping both boards. Is replacing the flyback unavoidable? All my searches for a new flyback are very cost prohibitive.

 

I have a few other compact Macs that I could potentially "steal" a flyback from but I honestly really want to avoid killing a working computer. I'm also not even 100% sure that I can just swap the flyback from one of those machines, I'm not sure they're compatible with each other. My spares are a regular SE, a Classic and a Classic II, I'm guessing the flyback in the SE could be swapped into the SE/30, but probably not the Classic or Classic II.

 

Any advice/recommendations are greatly appreciated!

 

Thanks from Canada :)

Sal

 

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That flyback transformer looks like it has had a very difficult life. The brown glue around the center post started off as a light tan color, but it looks pretty burnt to me at this point. The brass-colored bracket probably needs to be connected for a reason (I think it has to do with grounding). I think that this is worth replacing, if you can find the parts to do so. I've read that spare transformers have become quite rare at this point, so you may have better luck buying an entire replacement analog board.

 

@JDW may have some additional thoughts on this topic, as I know he made a video about bad flyback transformers a couple of months ago.

Edited by davidg5678
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5 hours ago, davidg5678 said:

That flyback transformer looks like it has had a very difficult life. The brown glue around the center post started off as a light tan color, but it looks pretty burnt to me at this point. The brass-colored bracket probably needs to be connected for a reason (I think it has to do with grounding). I think that this is worth replacing, if you can find the parts to do so. I've read that spare transformers have become quite rare at this point, so you may have better luck buying an entire replacement analog board.

 

@JDW may have some additional thoughts on this topic, as I know he made a video about bad flyback transformers a couple of months ago.

 

Thanks for the advice, yes I'll keep searching for a replacement but hoping I can get by for a while with the one that's in there. I watched JDW's video from beginning to end (super helpful!), I sent him a private message a few days ago but haven't heard back yet so I figured I'd post something in the forums. Thanks every for all your help, much appreciated!

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4 hours ago, bibilit said:

To be honest, if it's still working fine, i will leave it that way.

 

never seen a bad flyback on an SE or SE/30.

 

If you find a spare you can swap parts in the future, many SEs can be found for cheap if the Logic Board has been destroyed by the battery.

 

Thanks! I'll see how it's running once I'm done with recapping it and keep my eyes peeled for a replacement parts-only SE/30 analog board.

 

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@netbeui Thank you for your question, and I am sorry I missed your PM.  That was sent at a time when email notifications were dead on this forum, so I never got alerted to it.  I do see your PM now though.  

 

I replaced a flyback with the same broken bar as yours, shown at 39:14 in my video below.  I experienced occasional jittery with that flyback just as you are reporting with yours.  I also made a separate video which shows a different bad flyback which has high voltage leaking out, but since you said you cannot see any blue light, there's probably no arcing.  Even so, if you smell ozone, there's definitely a voltage leak you are not seeing, which would require replacement of the flyback.

 

The big problem is that "new" (old stock) flyback are now being sold for about $150, which is crazy expensive in my opinion.  Most people try to salvage them from another Mac.  Since flyback do go bad, what we really need is a brand new production of flyback to keep our vintage Macs running well into the next century.  Without that, at some point, all our flyback will eventually fail.  Those parts don't have eternal life.  Then again, neither do CRTs as per screen burn-in.

 

 

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8 hours ago, JDW said:

@netbeui Thank you for your question, and I am sorry I missed your PM.  That was sent at a time when email notifications were dead on this forum, so I never got alerted to it.  I do see your PM now though.  

 

I replaced a flyback with the same broken bar as yours, shown at 39:14 in my video below.  I experienced occasional jittery with that flyback just as you are reporting with yours.  I also made a separate video which shows a different bad flyback which has high voltage leaking out, but since you said you cannot see any blue light, there's probably no arcing.  Even so, if you smell ozone, there's definitely a voltage leak you are not seeing, which would require replacement of the flyback.

 

The big problem is that "new" (old stock) flyback are now being sold for about $150, which is crazy expensive in my opinion.  Most people try to salvage them from another Mac.  Since flyback do go bad, what we really need is a brand new production of flyback to keep our vintage Macs running well into the next century.  Without that, at some point, all our flyback will eventually fail.  Those parts don't have eternal life.  Then again, neither do CRTs as per screen burn-in.

 

 


Thanks James, I appreciate it. I don’t smell anything so I’m hoping to get a bit more time out of this SE/30 before having to replace the flyback. I’ll keep searching for a replacement though, wish me luck! :)

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3 hours ago, netbeui said:


Thanks James, I appreciate it. I don’t smell anything so I’m hoping to get a bit more time out of this SE/30 before having to replace the flyback. I’ll keep searching for a replacement though, wish me luck! :)

 

Well, the only two compatible flybacks currently sold that I know of, which are most likely "new, old stock" (very old, probably), are these:

 

https://www.ebay.com/itm/157-026C-Flyback-157026C-Replaces-Apple-HR-42031/121655780759

 

https://www.donberg.ie/descript/h/hr_42031.htm

 

"Good luck" finding one for less than those prices though. :-)  And to think, these flyback used to sell brand new back in the day for around $30 or less.  With China copying nearly everything these days, you'd think someone would have copied a compatible flyback by now.  Oh well.  Maybe one day!

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@JDW I actually explored the idea of making new cheap flyback transformers in a low quantity of 100 units.  Here is a thread where it is discussed more in detailed: 

Long story short, it required too many custom parts that are no longer produced.  It could be done if additional parts were made by me but the target cost probably would have gone from $39 to $99 per unit.  I doubt more than a dozen people would have purchased such a unit.  Thus, an insufficient market and lack of parts causes issues again.  

 

I too would not use the OP's flyback, it should be replaced with a used or new one.  

 

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2 hours ago, maceffects said:

...$99 per unit.  I doubt more than a dozen people would have purchased such a unit.

 

Thanks for mentioning that, Mark.

 

In light of the current market charging $149 per unit, even a $99 per unit price tag would be a rich blessing indeed!  Another consideration is the fact that the current units being sold are no doubt "new, old stock." That means they are not being produced but rather being sold from old inventory.  Eventually, even at a whopping $149 each, that stock will sell out (and the price will probably break $200 before then too).  When that inventory is gone, the only recourse people will have is to salvage from another machine.  But if one's other machine is a functional machine, one cannot salvage a flyback from it.  Add to that the fact flybacks won't last forever, and you've technically got a market for such a flyback.  It's amazing all the vintage Mac buying and selling I see going on even during this horrible year of Coronavirus, lock downs and job loses!

 

I don't have time right now to read every post in that 3 page thread, but I did cast my vote just now, and I searched for the word "kick" on each of the 3 pages and got no results, so I guess KickStarter has not been considered, right?  Even if "now" is not the time for you to seriously consider it, I am quite certain that day will come in the next few years.

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As others have said, flyback replacements are expensive and hard to come by. The best way is to find a used, good condition analog board and pick the flyback off that (or just replace the board entirely if the replacement board works ok).

As has already been pointed out, look out for a flyback with a light-coloured seal (the original colour was yellow), darker colour indicates the flyback was used a lot.

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