nicely sounding with J271
scarce, sorta easier to find in SMD ........ (from top of my head) MMBF271, or something as that
@Mark
J105 is nch, but J175 is pch..i am not sure how related they are, but both are indeed designed for switching aplication. Even this j175 one has not so great transconductance etc compared to j74, it is no replacement for sure.
@Zen
I looked into getting it, but even that becomes a game of chasing sketchy sources so it is not that much more convenient than just getting j74. Plus, isn't it a pretty noisy one?
J105 is nch, but J175 is pch..i am not sure how related they are, but both are indeed designed for switching aplication. Even this j175 one has not so great transconductance etc compared to j74, it is no replacement for sure.
@Zen
I looked into getting it, but even that becomes a game of chasing sketchy sources so it is not that much more convenient than just getting j74. Plus, isn't it a pretty noisy one?
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That's alright Mark, it really happens 
In related news im making a PCB (for personal use).
Comments are welcome, since I plan to publish gerbers later once its all revised and tested (of course, also for non-commercial use only), I have an interest to get it right.
J74 conveniently has the same pinout as J175, so board can also be used by people with greenies for j74's.
Edit: i wanted to just note that the design seems a bit schizo (for example, why aren't the 4 output resistors all conveniently next to each other?) because i have a strict design requirement of no side being more than 10cm. PCB manufacturing cost goes way up above that.
Here's what i have so far. (attachment)
In related news im making a PCB (for personal use).
Comments are welcome, since I plan to publish gerbers later once its all revised and tested (of course, also for non-commercial use only), I have an interest to get it right.
J74 conveniently has the same pinout as J175, so board can also be used by people with greenies for j74's.
Edit: i wanted to just note that the design seems a bit schizo (for example, why aren't the 4 output resistors all conveniently next to each other?) because i have a strict design requirement of no side being more than 10cm. PCB manufacturing cost goes way up above that.
Here's what i have so far. (attachment)
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noise is not a problem in this particular case
why you just don't pony up for Store LSJ?
yes, feels expensive comparing to situation from 10yrs ago, but you're not building J every day
Very true, but i enjoy maximal DIY, feels nice to go off the beaten path even for a little bit. J175 has same pinout as lsj74, so i can always splurge and pop them im later.
But on a serious note, im on a rather silly quest to build the whole thing under 100usd (this is actually almost a third of my whole monthly income, so imagine for an American this would be 1-3k$ equivalent). Such is life sometimes, just gotta roll with it and see what you can do.
Actually as crazy as it sounds i already did this, my current Aleph 3 (with one output stage, so mini) was around 100€. Most of the components are not expensive, PCB's i get made myself, and heatsinks i bought from a Serbian guy for 25€ a pop (4.5kg each, used for industrial use, even have fan mounts). Works like a charm. I will reuse the heatsinks. I'll even throw in a cap multiplier juma style
Pics come after it's all said and done (hopefully), but for now just imagine something very janky.
Dalmatia
I used to have a flag but i realised there is not many of us here. So then when i say something stupid, and people see the flag, i embarass the whole country. Now i only embarass whole EU.
If you're not nice to me, i will set it to Serbia and tarnish the years of the reputation you and juma built
just joking of course you can be not nice all you want
Second amp board up and running, also zeroes offset really nice. Reduced R23 to 27K on this one, a bit lower initial IQ so maybe I’ll make the same change to the other side.
Lovely build so far. Approx 5-7 hours work per side from start of stuffing to up and running. But maybe I am slow, dunno. Very happy so far.
Regards.
Andy
Lovely build so far. Approx 5-7 hours work per side from start of stuffing to up and running. But maybe I am slow, dunno. Very happy so far.
Regards.
Andy
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Dalmatia
I used to have a flag but i realised there is not many of us here. So then when i say something stupid, and people see the flag, i embarass the whole country. Now i only embarass whole EU.
If you're not nice to me, i will set it to Serbia and tarnish the years of the reputation you and juma built
I like Dalmatia ....... spending week or two for most of my kid years in Vodice with sisters and Aunt, while rest of summer being in Zrmanja Vrelo,at my GrandMa's
Dalmatians are terrible people ......... so send me your snail mail addy in PM, and I'll send you small envelope with enough matched J271 for 2 Aleph J
plenty of Babelfish J (both early and later scalable iteration) are made with J271; I couldn't differentiate them singing with original Toshiba and these, even if there is some difference in measurements
in any case - substantially better than with 175 or 176
damngreenhorns
they took all my tricks
It’s important to know who you are stealing from, and if they mind being ripped off or not
Thank you! A Zardoz outfit is in the mail
Something like this: https://m.aliexpress.com/item/32909...7d18bb121ce60b5c38c63f27f15f7055fd21f7&gclid=
Wow, very generous!
I agree, i am the most terrible one of them all so i will shamelessly take you up on your offer
Looks like i owe you a beer or two next time you're in the area
Andy, for the outputs, just wondering how warm @ your preferred bias with those sinks. Of course when your able to reach complete closure. Thanks