Lindell 506 lunchbox fuse trouble

[barbaroja]

Some slots god distorted sound as the analog allstars pultec. I figured out something should be wrong with the power delivery, so checked these orange thingies and well the bad slots were with a high resistance in those. They are marked JK6050. They go in line with the +16 and -16V rails, feeding power to each slot.

May I replace those with something else more reliable?
Any ideas about the cause of failure?

Right now I have 3 slots where modules distort, and I am suspecting of another slot where the fuse reads ok but I am not sure its working within spec. they are supposed to open when current gets higher than certain point.

I am attaching pics and the fuses datasheet.

 

[barbaroja]

Pic

 

[mitsos]

Looks like those PPTC are out of spec.  Those slots are probably getting a lot less voltage due to the voltage drop in the PPTC. You could remove them and stick a jumper in their place,  I don't think most racks use them.  API for example uses PTC thermistors on the modules, not the racks. 

 

[barbaroja]

Yep . Bypassing solved the issue. Still think its a good idea having some sort of overloading protection but, somehow, the differences between -16v rails was changing the output level in some modules. For example, the analog allstars EQP1S, sounded softer in one spot. So I am now debating if using them or not.

 

[mitsos]

Like I said, I haven't seen these in any other racks.  Not a bad idea to have them,I guess,  but it's one more thing that can go bad, so....

....just sayin'....

 

[barbaroja]

Further research showed these being generic switches.  Maybe using a lil better quality/brand name on those spots would solve it. I think will do. What eludes me is the reason for failure. Going out of spec on so many places seems shady to me.