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Thread

Advice for a broken Emax !

2014-09-11 by johnny@...

Everyone,

I had an Emax SE rack I wanted to upgrade to SCSI, but the CPU board was Rev 2, Ver C. I was unsure if the SCSI kit was going to support it, if I could get one, or if it was worth the effort. I found a 2nd Emax SE on ebay that "had SCSI and a HD" already installed. It was was being sold for parts - the seller said the power supply was bad. The price was right, so I bought it. I had asked all the appropriate questions beforehand, but when I received it, not only did the unit not have SCSI or an HD (the seller mistook the very large original internal floppy for an HD), but the CPU was a PC333 Rev A... and it was broken. So I was no closer to getting SCSI installed than I was before the purchase.

I contacted the seller, and he was very understanding. He refunded my money, and let me keep the unit as well, since neither of us wanted to deal with or pay for return shipping (I ended up buying another proper CPU board rev, with SCSI actually installed a short time later. It's now installed in my Emax SE and is working perfectly...). I was glad to keep it, since I needed it's rack ears, and I thought I might be able to resurrect it, somehow.

While installing the new motherboard in my Emax SE, I attached my working power supply to the dead Emax and tested it. It still would not power up, so the problem must lie elsewhere.
But that's the extent of the testing I could do. I can swap parts, install new backlights, sliders, knobs and buttons, but I've never traced circuits, re-capped power supplies or installed new ICs, etc.

So my question is: What should I do with this non-functioning Emax SE (and the original CPU board from my working Emax SE)?

I don't need a second Emax, so I don't really want to spend the money to repair it, and whatever's wrong with it is beyond my present experience to repair myself.
I hadn't felt comfortable selling it, since I can't really say what's wrong with it. I also don't want to trash it (actually, recycle...), unless I have to.
I thought, at least, there would be some parts I should pull before I did, but I'm not sure which those would be (the SE chip? Can that be re-used in another Emax? The filter chips?).

I'd be grateful for any opinions.

Thank you for a great community.

Johnny.

Re: [emax] Advice for a broken Emax !

2014-09-11 by Ted Summers

Johnny-

I still sell SCSI kits, SE update disks (although you can make them for free from the group files section).

I do look at boards (I've fixed 5 out of 6 sent to me), and Jammie (here on the group) is an authorized tech in the UK.

As far as just keeping it for parts- you could do a couple of things- many of the relevant items are socketed and you would want to keep the Scanner CPU, the NS32000, the Echip itself, etc - basically if it';s socketed keep it.

With that said- if you are in the US, where you have a potentially bad board and are just going to throw it away I would be happy to see if I can fix it for a spare.

Contact me directly off group and I can send you some money for shipping via paypal.

Regards,
Ted Summers

Yahoo! Emax User's Group Co-Moderator

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On Thu, Sep 11, 2014 at 8:21 AM, johnny@... [emax] <emax@yahoogroups.com> wrote:

Everyone,

I had an Emax SE rack I wanted to upgrade to SCSI, but the CPU board was Rev 2, Ver C. I was unsure if the SCSI kit was going to support it, if I could get one, or if it was worth the effort. I found a 2nd Emax SE on ebay that "had SCSI and a HD" already installed. It was was being sold for parts - the seller said the power supply was bad. The price was right, so I bought it. I had asked all the appropriate questions beforehand, but when I received it, not only did the unit not have SCSI or an HD (the seller mistook the very large original internal floppy for an HD), but the CPU was a PC333 Rev A... and it was broken. So I was no closer to getting SCSI installed than I was before the purchase.

I contacted the seller, and he was very understanding. He refunded my money, and let me keep the unit as well, since neither of us wanted to deal with or pay for return shipping (I ended up buying another proper CPU board rev, with SCSI actually installed a short time later. It's now installed in my Emax SE and is working perfectly...). I was glad to keep it, since I needed it's rack ears, and I thought I might be able to resurrect it, somehow.

While installing the new motherboard in my Emax SE, I attached my working power supply to the dead Emax and tested it. It still would not power up, so the problem must lie elsewhere.
But that's the extent of the testing I could do. I can swap parts, install new backlights, sliders, knobs and buttons, but I've never traced circuits, re-capped power supplies or installed new ICs, etc.

So my question is: What should I do with this non-functioning Emax SE (and the original CPU board from my working Emax SE)?

I don't need a second Emax, so I don't really want to spend the money to repair it, and whatever's wrong with it is beyond my present experience to repair myself.
I hadn't felt comfortable selling it, since I can't really say what's wrong with it. I also don't want to trash it (actually, recycle...), unless I have to.
I thought, at least, there would be some parts I should pull before I did, but I'm not sure which those would be (the SE chip? Can that be re-used in another Emax? The filter chips?).

I'd be grateful for any opinions.

Thank you for a great community.

Johnny.

Re: Advice for a broken Emax !

2014-09-11 by Lorne Hammond

and since you have two and one works, why not open them both, disconnect the
power supply in each and with a VOM measure the Powersupply of the "bad" one
against what the VOm shows for ther good one.  It maybe that as you said,
the problem is elsewhere but both power supplies maybe good.  If so that
would be useful to know in terms of parts.  Lorne

Re: [emax] Re: Advice for a broken Emax !

2014-09-11 by JAMIE logan

echips are ok if socketed but most are socketed but have extra connections on because of faulty pins so they had to add extra circuits and trimmers to get them to spec

as a lot of the echips voltage reference was not to spec so they had to do these mods to get it with in the specified region

you will find on the ref333 boards that these mods are incorporated into the pcb and the chip

also if you are getting nothing when putting a good supply on it

check the power connector on the digi board for cold solder joints as they can crack and no voltage gets through youy can check this by testing the 5v pins on the logic circuits and the cpu and ram as if the 5v is not getting through you have a dead board

chips to definitely keep is the scanner cpu at £50 a pop and epr does not have any more

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On 11 September 2014 16:38, 'Lorne Hammond' lhammond@... [emax] <emax@yahoogroups.com> wrote:

and since you have two and one works, why not open them both, disconnect the power supply in each and with a VOM measure the Powersupply of the "bad" one against what the VOm shows for ther good one. It maybe that as you said, the problem is elsewhere but both power supplies maybe good. If so that would be useful to know in terms of parts. Lorne