Neve 1290 in 2U rack draw

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Spencerleehorton

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Thought I’d share a bit on this build as I looked at the £39 2U rack draw and thought, I know what to do with one of them!!!
 

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Spencerleehorton

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No smoke but a few adjustments needed, the gnd scheme always catches me out!!
This case isnt ideal but I’ve drilled 3 holes in the front so the two parts of the case are grounded together.
Will sort the polarity switch just before the output.
 

Spencerleehorton

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I suspect a short on B from the txf, I will disconnect the txf at B and see, check continuity, it’s either that or the R3 68k resistor!!
I was getting 24v on all primaries of output txf and meant to get less on B as it should be dropping the voltage down to about 20v?
 

Spencerleehorton

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Both channels working now, cold solder joint on txf of ch1, just need to adjust gain setup now by tweaking the 91R resistor on U/V of the b284 pcb to level match both channels. Less resistance more gain obviously, R10 390R + 100R trimmer then I’ll just dial it down to level match both channels.
 

Spencerleehorton

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Couple of issues, one with channel B not having the same gain as channel A and I don’t seem to be able to adjust the gain with adjusting the 91R down in resistance?
Also on one channel on pin2 I’m getting 5.2v and pin 3 only 1.2v? Again could be a txf issue need to trace and find out where it’s going wrong.
48v all working fine.
Another little gnd issue I need to sort as well, so not quite home and dry!!
 
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