Emu XL-7 & MP-7 User's Group

$152 does not seem like such a bargain when there is a reasonable chance that 
the main board is also damaged and that it would likely need replacement as 
well. Its all a question of risk that you're willing to sustain.




________________________________
From: Matt <somatt@...>
To: xl7@yahoogroups.com
Sent: Sun, November 14, 2010 7:36:49 AM
Subject: Re: [xl7] Re: my XL-7 does't start anymore !!!

   
New power supplies and new main boards are avail at epr. 
On Nov 13, 2010 1:33 PM, "Jack Pratt" <woodsworth1@...> wrote:
>
>
>  
>Fuse?
>
>My XL7 doesn't have a fuse. Unless there's one inside the power supply enclosure 
>(which I would doubt due to its inaccessibility - there might be a polyswitch 
>["ptc device" or "resettable (thermal) fuse"]). And there's no brown and/or 
>yellow wires.
>
>It has a 10-way single-in-line (molex type) connector on the main board [with 10 
>wires coming from the power supply] and next to the connector (on the main 
>board) there's a list of the voltage on each pin [+15, -15, GND, GND, +5V, +5V, 
>+3.3, +3.3 and two others]. Although there are individual wires from the power 
>supply to this connector there are no brown and/or yellow wires as it turns out 
>[purple, green, black red, orange...]
>
>It may be that you have a different variant XL7 than I have but I would be 
>surprised if  there were multiple revisions of the XL7 main board so radically 
>different. 
>
>
>In any case I would surmise that the most-likely problem is that your power 
>supply gave up and possibly the main board could have been damaged in the death 
>of the power supply. There is no value in turning the power on and risking 
>further damage to the main board. If you disconnect the power supply (from the 
>main board) you could check the no-load voltage on the power supply connector 
>and check what happens under load [if you put a 1K resistor across any two wires 
>the voltage should change not at all if the power supply is working properly, 
>even a 10ohm resistor should have little effect (except perhaps on the +15 and 
>-15 sources which would be unlikely to sustain 1.5A) if applied for a _very_ 
>short time]
>
>Solution:
>
>If you can verify that the power supply is defunct then get a new one [although 
>if you were sufficiently skilled in electronics you might be  able to fix it], 
>but the main board may also have suffered damage. The 'new' power supply will 
>probably have the same source as the 'new' main board - ebay.
>