SX-Amp and NX-Amp

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Regrettably, a lot of these great small signal TO-92 devices are going EOL and will only live on in SOT23 form. Once the kx2 is done, I doubt I will be doing anymore DIY amps using small signal TO-92 (all my commercial designs have sued SOT23 since 2016). The situation will only get tighter for the older packages.

TO-126 will probably be around a bit longer because of creepage and power dissipation benefits - but SOT223 is a pretty nice package IMV - although not as easy to heatsink - great for VAS duty through.
 
www.hifisonix.com
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Looks like a very long lead time for 771-BZX585-B4V7135. Closest potential sub I noticed at Mouser is 621-BZT585B4V7T-7 , but the zener current is much higher than the specified part.

That will still work - just make sure the package size will fit on the board.

Looks like I should revisit the nx-Amp BOM - it’s 9 yrs old this year! Some of the stuff has clearly gone EOL and were in the middle of a semiconductor shortage as well.
 
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Andrew, thanks. I'll sit down tonight and review the footprints to make sure nothing is askew with this potential replacement.

Yeah, thanks to the latest projects, I'm comfy with the surface mount stuff, but I know there are some on the forum that are really bothered that the old favs have gone into the thin air.
 
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Good news/not-so-good news on the 22mF caps that I ordered from Digi-Key. The cap diameter is fine. But the snap-in leads are slightly wider than Panasonic caps. I attempted to seat the caps but they are digging into the solder pads and I am a few mm from getting them seated properly. My thought is to file the leads down so they will seat properly.
 
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Update - I pulled out one of my saw files and went to work. I could only get down so far to the body of the cap, but the cap sits about 1/2 mm from seating perfectly. I guess I can lay down some electronic safe silicone adhesive and call it a day.

The Tiger Toroid arrived - a big, smelly, ugly beast that I expect to play fine music soon. I put it in my hot garage to bake some more as the family will be put off by the smell. I'm jazzed to have it and will plug away bit by bit on the amp as a Summer project with completion by the Fall. I have two other projects slated for completion this Summer, plus our privacy fence blew down and the wife made it clear that she needs me to repair it asap.

Andrew, as always, thanks for the help!
 
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Andrew, distributors have 0 stock on the Kemet 1000 uF 16V electrolytic. I see it's a general type but available alternates fall short in some parameter compared to the Kemet (life, operating temp, are low ESR, or ripple current is lower than the specified part). Is there any give/flexibility in any of these parameters that would fit the bill?