Coco BTJ-9000

Pete is, as always, being humble.

The Matching SUT for this phono stage is equally substantial

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Still enough room for the kitchen basin :smile:

Heat sink???

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So do I fire it up this weekend?

:cold_sweat:

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:+1:

Not the best terminology, granted :joy:

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Lol, I see what I did there now. Freud wound have a field day.

Letā€™s get drunk tonight and you can set up your turntable :+1:

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Thereā€™s a seduction technique you donā€™t often see.

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Whack it on with a broom just in case.

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It looks fantastic, and Iā€™m sure itā€™ll sound the same. Good to see that craftsmanship is not dead !

VB

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Thank you! Not sure I could be called a craftsman, but I aspire to it and am learning all the time. (Mainly about how much I donā€™t know)

You and me alike ! I fear I may have to learn how to desolder a 14-pin TSSOP without frying the hair-thin pcb tracks underneath it later today :-(.

VB

Oh boy. :frowning:

The SMD stuff is a nightmare.

Hot air rework station is your friend.

Thought they were platinum :smile:

True, although they can risk loosening a lot of other stuff. I have a mate who has a fitting for his Metcal iron and I might arrange to go over to him.

The annoying thing is that there are five chips all wired to the same 5V Vcc line and one (I think) is duff (trying to pull way too much current). I can only find out which one it is by disconnecting them. I canā€™t even slit the individual Vcc tracks (not that Iā€™d do that with a customerā€™s pcb in any case) because at least some of the chips are supplied by a track which runs from the Vcc pin back under the chip body and is then viaed down into the 5V rail on the pcbā€™s underside.

My last trick will be to see if I can detect one of the chips running hotter than all of the others.

VB

good luckā€¦

If you donā€™t need the chip snip itā€™s legs off first. Or make an attachment that will heat all the legs up.

I could (with care) but theyā€™re not pennies each http://uk.farnell.com/maxim-integrated-products/max5437eud/digital-pot-50k-single-tssop-14/dp/2516224. Furthermore the manufacturer (allegedly) characterises each one and programs their individual properties into the microcontroller which manages the volume and balance settings. So it would be best not to trash any that I donā€™t have to.

VB