The SLB (Smooth Like Butter) Active Rect/CRC/Cap Mx Class A Power Supply GB

[ppap64]

**** GB2 Interest List *****

analogdiy - 2 SLB - GB2
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Asuslover - 1 SLB - GB2
Morde - 1 SLB - GB2
ppap64 - 6 SLB - GB2

 

[slk23]

The Q10 transistor (Toshiba 2SA1943N(S1,E,S)) is out of stock at Mouser and Digikey. Is there an acceptable substitute? Would this work?

NJW0302G

The specs look similar although the "DC Current Gain hFE Max" is lower for the ON Semiconductor part.

And if changing Q10, would Q12 also be substituted?

 

[xrk971]

Try TTA1943Q, same part basically. 327 in stock.

TTA1943(Q) Toshiba | Mouser

Fairchild's NJW's can work well too as long as similar Hfe and current rating. If Hfe s a bit lower, that means the ripple control will be a little less but it will still work quite well.

Q12 can be TTC5200Q:

TTC5200(Q) Toshiba | Mouser

 

[asuslover]

can those transistors be replaced by mjl21193/94?or mjl4281/4302?

 

[slk23]

Try TTA1943Q, same part basically. 327 in stock.

TTA1943(Q) Toshiba | Mouser

Fairchild's NJW's can work well too as long as similar Hfe and current rating. If Hfe s a bit lower, that means the ripple control will be a little less but it will still work quite well.

Q12 can be TTC5200Q:

TTC5200(Q) Toshiba | Mouser

Thanks. Order placed and looking forward to putting the SLB PSU together this weekend.

 

[md_Stryker]

Here is a Mouser project based on the May 3 BOM with updates that can be used to create an order: Mouser Electronics

Enjoy,
-Michael

 

[Vunce]

Parts lists are always a great help
Thanks Michael!!

Happy Building

 

[xrk971]

md_Stryker,
Thanks for making the BOM/shopping cart for us. To folks wishing to use this BOM/shopping cart - please save as your own project before modifying it, else stuff gets deleted/changed for everyone clicking on this link.

For All,
As a validity check, the total BOM cost is $90.28. SO if that checksum doesn't pan out, you may need to review it carefully.

Thanks,
X

 

[yoaudio]

Boards received.

Thanks X

 

[xrk971]

Glad to see the packages arriving. Let’s see who gets one up and running fastest.

My bet is on Vunce.

 

[Vunce]

I received mine also X, thank you!
There was a bit of solder slinging going on last night
Just a few parts left to install. I still haven’t decided if I should socket the LT4320’s?

I have one request, PLEASE use blue painters tape when packing. The clear packing tape residue took forever to remove

Cheers,
Vunce

 

[xrk971]

Sorry about the tape, Vunce. Try mineral spirits paint thinner - comes off in a jiffy. I recently switched to a different brand of packing tape, and I think it probably leaves more residue vs the more expensive version that is silent upon unrolling. You know the screechy sound that comes when you apply packing tape?

Your build is looking good. Thanks for the update.

I soldered the 4320’s direct without using sockets. They are reliable chips not expected to burn out like an opamp.

 

[yoaudio]

Isopropyl alcohol works good for removing tape residue.

 

[Vunce]

Thanks for the residue removal tips guys.
Actually, I used WD40 and that works great for removing sticky stuff. Then cleaned the boards well.

I was thinking of socketing the chips not for fear of failure, but to limit the number of LT4320’s I’d have to buy. They can be removed from a unit not being used and re-installed in a currently used amplifier. At almost $10 per chip, they add up quickly.
You guys know how amplifiers seem to multiply like rabbits

Vunce

 

[xrk971]

Hi Vunce,
Very good point about moving the LT4320 around! That reason alone is totally worth it!
Thanks for the idea.
X

 

[Vunce]

Hi X,
Shouldn’t R17,18 on the SLB schematic and BoM be
reduced to a value between 1R-2.2R?

 

[xrk971]

Yes. 10R will ensure no oscillation but you get more ripple reduction at lower value and we have run st 1R and 1.5R. 2.2R should be very safe though.
Thanks.

 

[skunark]

Thanks X! The boards arrived today.

Next batch can you avoid the packaging tape, the heat can make it a sticky mess on the PCBs.

 

[md_Stryker]

Mine arrived as well. Thanks X!

-Michael

 

[Shawnstium]

I stayed late at work to start the build. The PCB is beefy! I had to put the big tip on my soldering iron to get the 15kuF caps on because of all the beefy thermal mass.