So you have Blown it ?

[colinh]

To the greatroberto .Let's know what 's blown

[thegreatroberto]

This thing is driving me NUTS !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

All was well,bigger caps,heatsinks,new pot..............and it even sounded good !

then I decided to "refine" a few things.

SIL pads and bushes for the heatsinks.
Adding some solder to the tracks of the TIP trannys.( the heat over the years had lifted the tracks).

So when i put it all back together , there was a bad smell.........to be fair the smell was there when i stripped it down,but not to the same extent.And the smell brought with it some smoke.......quite a bit in fact !
Anyway, the TIP 110 tranny under the PSU was black so were the 2 10R resistors..............Not to worry i thought,as I have some spares.Spares were fitted, but it made no difference.Well, no smoke this time though!

I then discovered that I had a small blob of solder accross the TIP115 and the other tranny its connected to.Fixed that, but still dead !

And there it is .All was working well,until I decided to refine it just too far !
Anyway i enjoy a challenge,but this is reaching my limits of expertise now !

I thought that all that extra resistor burning current may have taken out the diodes in the PSU.But they are fine.Oh and another thing. Those 3300 FC caps I've fitted.Those bastards hold a significant charge for over a week ! I bit of prodding with my meter the other night and I made a few sparks !

Next step is to remove the heatsinks.Whatever is killing the X-can, it's doing it to both channels.
Watch this space !

[colinh]

That sucks ! I have to admit that when I opened the X Can I noticed that the 110's and whatever
it's mated to had two pins joined .{my eyes now not always good enough to read ic's ect.
however I assumed that the solder join was how it was made. but I did put insulating pads on
both sides of the heat sink . I will send you a pm with my contact details cheers for now.

[thegreatroberto]

Just checked.It's definately teh TIP 110 tranny (under the psu board) that smoked.I had started to convince myself it was the TIP 115...............Two of the legs are nicely black.However I think what actually burnt was the board rather than the componants.Either way, the X-can is still dead.

The more you think about it, this thing really is crying out for ventilation.Maybe not Pink Floyds two drilled holes in the top, but something better than what it gets.

In its factory state I can't believe that you can leave it on 24/7 ( like is says in the "manual")............

And there's another thing.MF "manuals"...........Aren't they crap !It doesn't matter if its a £129 X-Can or a £2300 power amp.A bit of photocopied paper........ ( and Jamicon caps !).I suppose they claim you hardley need a manual for many of their products (and you don't) but really.............................

Actually what they could give you is...........
A circuit diagram, the original design intent, the areas where they have skimped and the areas where money should be spent (by you in an attempt to get to to sound better).........There's an idea !


Rant over !

[colinh]

I have to admit that you have a point re MF the trouble is that like any other maker these days everything is made down to a price. I can actually remember at one time you used to get circuit diagrams when you bought a radio.
That shows how old I am ?. Back to the amp , It might be worth while checking for continuity of the tracks. Also Id check that the Valve heaters have not blown . in case they went
over voltage ?

[thegreatroberto]

The funny thing is with this dead X-can,is that there is small amount of life somewhere in it.
The LED lights up as do the the valves.However the darlington transistors don't warm up.There's a simple answer to this, but i can't find it !

[colinh]

So if led ok and heaters ok that looks like they use the same
power transistor . If it was mine that had blown the next thing would be to get a spec sheet for the Darlington's and
then check the pins with a diode tester {on your multimeter}
if you have one with this feature. Also check for dry joints.
Sorry this is a puzzle when I cant see the unit. As you say will
be something or nothing when you crack it.

[thegreatroberto]

Thanks.The bit that is confusing me is that it's both channels that are duff.It's as if the source is not connected to the amp ! Even when you psuh/pull the 'phones in/out.
Anyway,It's being dispatched to the guru !!

[themystical]

My recently modded x-canv2 has done the same! The 2 10R resistors look charred as the general area below the two transistors. When I measured the resistors, they still seem to measure around 8 ohms so they have not blown.
It looks like exactly the same issue as the Great Roberto's x-can so it would be good to understand how that was repaired.

[thegreatroberto]

Ah..............the v2.I'd almost forgotten about that one !
I contacted MF to see if they had any ideas,but no luck.In fact they were not intrested.As soon as I said it was modded................Even it it was not, I was looking at about £150 from MF.
In the end it drove me nuts so went into the loft, and I bought a V1.
Whatever it was , the original fault took out the psu section.(well the small trannies).I replaced these,but still no luck.
I bought the V1 as i reckoned these have a longer life.No big trannies kicking out heat.Forget what the MF blurb says, these things should not be left on 24/7.............well not if you want them to last a lifetime !