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Linn Classik Movie Di - DOA

DonaldStott

Donald
Just took delivery of a Linn Classik Movie Di which was completely Dead On Arrival (DOA)!

On the assumption that it may be a power supply problem I removed the cover with the expectation of doing some investigative work with my DMM. Didn't get very far though as I quickly noticed that this was all that was left of the fuse:-



From the debris I was able to ascertain that this was a Bussman T6.3AL250V so have placed an Order for some of those. A bit surprised at the 6.3A and 250V - seemed a bit low to me?

In the meantime I carried on with the usual visual inspection but nothing out of the ordinary that I could see?

Did notice some scorching on C102 and inside the top of the fuse holder:-



Once the new fuse arrives and is fitted I'll update the Thread but conscious of the fact that I need to know what caused the fuse to blow on the first place!?

I'm also hopeful that someone can point me in the direction of a circuit diagram or other technical details for this Linn Classik Media Di.
 
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Probably worth replacing the two caps on the mains input with such an explosive fuse failure.

Hints at likely failure further into the psu, they're notorious for it
 
Thanks sq225917 - I had already assumed that it would never be as a simple as a new fuse!

Should be able to determine the cap values and types although a circuit diagram would be beneficial, especially further down the line ...

(I note that my images have only appeared as links as opposed to images visible in the Post - can't remember how to do that but hope someone can help?)
 
2n2 film caps, 250v, if they're across live they're class x ( or used as class x), if they're live to ground they're class y, and the 250v rating implies they're class y3 caps. The lowest class x voltage rating is 1250v

Confusingly you can use class y in place of class x, but not vice versa.

The actual difference is that class y are used where electrocution can result, class x where only fire can result.

I'd assume they're y3 used as class x, but a check on the pcb trace will clarify.
 
On Flickr, on bottom right of page there's a show all sizes icon, click this, select the size image you want, then right click that image to open in new tab, copy that url, it'll end in .jpg and paste it using the image button in the menu above the post.
 
Thanks sq225917 for the clarification regarding Class X and Class Y capacitors.

I'll hold off on any Order meantime until such times as I have a complete list of required components - I feel some SMD work approaching!

I've sorted out the image problem (see above) as I remembered that you need to use the BBCode to insert an image.

A circuit diagram would be beneficial.
 
While waiting on some parts to arrive I did some more visual checking and online searching regarding this Linn PSU - still unable to find a circuit diagram. My board says PCB254/L4.

In the interim I noticed that there are three two pin connectors at the mains input:-

P103 MAINS INPUT
P102 POWER SWITCH
P104 VOLTAGE SWITCH

Whereas P104 is connected to the mains input (CONN 624) and P102 is just a simple loop connecting both pins (CONN 707) I'm a bit confused as to why nothing is connected to P103? Can someone enlighten me and confirm that this is the correct configuration - thanks?



I've also managed to locate the 47uF electrolytic that seems to be suspect from reading other Posts. This will be tested and replaced if required.
 
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Apologies for the confusing Post yesterday which, amongst other things, said: -

"Whereas P104 is connected to the mains input (CONN 624) and P102 is just a simple loop connecting both pins (CONN 707) I'm a bit confused as to why nothing is connected to P103? Can someone enlighten me and confirm that this is the correct configuration - thanks?"

Of course it should have said: -

"Whereas P104 is connected to the voltage selector at the back of the chassis (CONN 624) and P102 is just a simple loop connecting both pins (CONN 707) I'm a bit confused as to why nothing is connected to P103 MAINS INPUT? Can someone enlighten me and confirm that this is the correct configuration - thanks?"

Apologies - but still confused?
 
The voltage switch connection may have been for a model with a 120/240v switch on the iec input. Possibly to a multi region smps.

They're just they're for flexibility and because the chassis and potentially psu board may be shared between different models.
 
Thanks, this model has a 230/115 switch on the IEC input.

Of course I have it on the 230V setting - so just wondering if those connectors are indeed in the right locations?

But possibly I'm just over-thinking the whole thing!
 
Maybe the voltage switch is for an internal only voltage change option. Without knowing the pcb and iec inlet I really can't say.

I have a Classik at home but am pretty sure it's quite different in terms of iec wiring
 
Got a bit impatient and decided to liberate the SMPS from the case as I need to get to the underside of that PCB to find out what is going on , or not going on!

A number of bolts of different sizes to locate and undo along with a hex pillar joining this PCB with the one below. After that it took a bit of wiggling to extract the SMPS PCB.

Here are some images: -

SMPS_1

SMPS_2

SMPS_3

SMPS_4

And here is a close-up of the back of the IEC socket/voltage selector: -

SMPS_CLOSE-UP

Now my next question is how to separate the PCB from the metal enclosure - you can see from the rear view (SMPS_3 above) that there are no further bolts to undo??
 
Afraid I'm not going to be any help here, I've never pulled a linn smps out of a unit before. I'm sure a suitably experienced fishing will be along soon.
 
Understood sq225917 but thanks for your help so far - much appreciated.

Meantime I'm still confused by the voltage selector and what all those pins are doing at the back??

Is there any way to identify the make and type?
 
The PCB may be stick down to the metal chassis with that nasty white gum the Chinese seem to use on everything?

I've never had much success getting it to give up it's hold....even with a heat gun on the back, you usually do more harm than good

Last one I did (a SMPS in a lipo charger a few weeks ago) I simply threw the old one away..got on eBay and bought another one of the right voltage/wattage ...and took the case off that and put it into the charger.
Repaired and Working perfectly and cost £9.90 delivered
 
Thanks Mynamemynaim but as you probably know Linn Products is an engineering company that manufactures hi-fi and audio equipment at their factory in Waterfoot just outside Glasgow. So no Chinese using nasty white gum here although I'm sure there must be something similar.

If you can find me a Linn Brilliant SMPS for sale then you are a better person than me!

Just to keep the Thread ticking along while I contemplate various strategies to separate the PCB from the metal enclosure, I've done a bit more prodding with my DMM and am measuring 127V AC coming out the back of the voltage selector. Does that sound about right to anyone?
 
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You'll get whatever goes in the front coming out the back, it's just an inlet with a switch.
 


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