I already made Babelfish M25, with Hall chips
Babelfish M25 R.2 - exactly what you are asking about, already been tested and measured, soon to have pcbs fabricated and verified on T-Bed
yes, no need for level shifter, in that case
though, there is also upcoming SET amp, practically Schaded M25, which is using small source follower level shifter to bias and drive Schaded mosfet
Babelfish M25 R.2 - exactly what you are asking about, already been tested and measured, soon to have pcbs fabricated and verified on T-Bed
yes, no need for level shifter, in that case
though, there is also upcoming SET amp, practically Schaded M25, which is using small source follower level shifter to bias and drive Schaded mosfet
Great projects as always ZM! Is it possible to post schemas of M25 R2 and schaded and SET Amp?
Is it mandatory to measure the current on both +and - rail? Couldn't it work with only one opto coupler in the positive or negative rail?
Is it mandatory to measure the current on both +and - rail? Couldn't it work with only one opto coupler in the positive or negative rail?
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I bet the answers would be two No, No.
But for this particular LuDEF, the answers could be Yes, No.
But for this particular LuDEF, the answers could be Yes, No.
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How do you like this output stage? Spice predict neg phase H2 with H2/H3 >20dB.
Code:
Harmonic Frequency Fourier Normalized Phase Normalized
Number [Hz] Component Component [degree] Phase [deg]
1 1.000e+03 4.000e+00 1.000e+00 0.33° 0.00°
2 2.000e+03 5.050e-03 1.262e-03 92.85° 92.52°
3 3.000e+03 4.206e-04 1.051e-04 1.99° 1.66°
4 4.000e+03 9.427e-05 2.357e-05 -140.21° -140.53°
5 5.000e+03 6.728e-05 1.682e-05 -179.65° -179.98°
6 6.000e+03 4.960e-05 1.240e-05 178.80° 178.47°
7 7.000e+03 4.230e-05 1.057e-05 -179.94° -180.27°
8 8.000e+03 3.716e-05 9.289e-06 -179.90° -180.22°
9 9.000e+03 3.304e-05 8.261e-06 -179.95° -180.27°
Total Harmonic Distortion: 0.126718%(0.132002%)Attachments
all in time, as acquiring final pcbs and puttin them to life on T-Bed
so, soon
of course possible, but better having same "additional" resistors in both rails; when having that, lets make everything else symmetrical, not just for sake of powering up/down cycles but for all phases in operation
do not forget that some of these wakoo amps are having unequal loading of rails in AC domain, especially SissySIT and future SET amp - up to clipping levels, two output parts are working one against other, speaker getting difference of currents, not sum, as in "normal" amps
as always when Mighty Indra is devising something, I like it 🙂
edit: I see that Pa spoiled you with his later time mischiefs - single rail, coupling caps everywhere
how's offset stability, temp/rail change?
Iq must be stable, huge reference
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I am keeping an eye on this thread. I was about to resurrect the old SissySIT thread in the trade forum. I was about to request a set of SissySIT PCBs in Option 1, then everything hit the fan and international shipping was stopped for many months.
One supposes the Ox carts in Serbia could have made it to the local post, but the trouble was crossing the Big Splash after that. 😉
I have several sets of parts for building something SIT-like: both Cinemag and Jensen iron, roughly matched and not so matched THF-51S pairs, well matched 2SK182ES, and even well matched 2SK180 D rank pucks.
Need to build something. Waiting for Pa to find a good use for the unmatched THF-51S pair, but the others are (mostly) unspoken for at this time.
One supposes the Ox carts in Serbia could have made it to the local post, but the trouble was crossing the Big Splash after that. 😉
I have several sets of parts for building something SIT-like: both Cinemag and Jensen iron, roughly matched and not so matched THF-51S pairs, well matched 2SK182ES, and even well matched 2SK180 D rank pucks.
Need to build something. Waiting for Pa to find a good use for the unmatched THF-51S pair, but the others are (mostly) unspoken for at this time.
<3% Iq change @ 10% rail variation. Basically it's an ACA gain stage configured as a follower mated to a P-channel.
believe it or not, delivery is functioning, even to States, even if little slower and even without any trace in US Post, once when it's landed on JFK
though, having some obstacles these days to cut through/wait enough in line in front of PO ..... end of month, older ppl paying bills, Covid rules not allowing more than x customers inside .....
it'll pass, as everything does
pc817 is of common variety, same as 4N25
I did found them being of decent current transfer ratio, decent uniformity, cheap
didn't tried any other in this prototyping, even if I have them
I did found them being of decent current transfer ratio, decent uniformity, cheap
didn't tried any other in this prototyping, even if I have them
that's good 🙂
while we at it (anything
) have a question for you:know for some decent P channel mosfet, preferably through hole T0-220-ish case, with Ugs in range of 1V5 to max 2V?
I did found TP2640 as best candidate, but taking care of T092 dissipation too much, never been my favorite activity....
logic level N channel everywhere, but P channel ones are hiding of me .....
That is very cool work - and - same approach as Papa when explaining, i.e. start with simple drawings and gradually step up, so even I have a chance to understand what goes on. Thank you.
Now we "only" need to find LU.
Now we "only" need to find LU.
eBay sellers have genuine LU. I have curved traced over 100 pcs and they are all genuine triode curves.
That is mostly Japanese 2SJ300-400 series, all obsolete. Still available are Toshiba J349, J438 (they use these to fake the J313), J338, J412, Hitachi J327, NEC J329 and a few others not as easily found, probably you like the 2SJ438 best. 🙂
@woofertester: Thanks for heads up. There is actually one seller that seems to have original parts, and they are reasonable in price. I will order some and see if I get BC547 🙂......I'll let you know.
Hopefully, I will then be a little prepared if ZM ends up being satisfied and perhaps says OK that we can try it out.
Hopefully, I will then be a little prepared if ZM ends up being satisfied and perhaps says OK that we can try it out.
whatever I throw on it in last few days, I like what I hear
though, having a problem now - I hear it is good, but can't find anything I don't like 🙂
tomorrow I'll get LuDEF to my friend Woland , to whom ears and brain I always trust ......... after all, his brain confirmed with fact that his entire amplification chain and speakers are my brainchildren (IP, SissySIT, few Tannoy boxes, Sonido boxes)
whatever, I'm expecting confirmation that this is a Monster, as I'm hearing it ....... even if I'm unable to devise satisfactory logical explanation of process resulting in so low THD
though, having a problem now - I hear it is good, but can't find anything I don't like 🙂
tomorrow I'll get LuDEF to my friend Woland , to whom ears and brain I always trust ......... after all, his brain confirmed with fact that his entire amplification chain and speakers are my brainchildren (IP, SissySIT, few Tannoy boxes, Sonido boxes)
whatever, I'm expecting confirmation that this is a Monster, as I'm hearing it ....... even if I'm unable to devise satisfactory logical explanation of process resulting in so low THD
my Buddy Zeljkor just sent me links for these .....
https://eu.mouser.com/datasheet/2/698/D16332EJ1V0DS00-1090103.pdf
https://eu.mouser.com/datasheet/2/308/2SJ652-D-1801598.pdf
though, TP2640 , which I already have in quantity enough to play with (same as cousin TN2640, great pair) is most probably final candidate
I'm certainly just hysterical thinking that 200mW for 1W declared T092 is problematic in any way
Will crank it to 300mW and put small heatsink
(Papa is abusing JFets regularly, 8mA at more than 24V, ZM is Chicken)
300mW is 24V 12mA, borderline linear for TO220 mosfets. TO92 part will likely perform much better and those Supertex part is rated 1W @ 25C ambient. The higher Rds(on) such as the VP0550 would be more linear at sub 10ma current but comes with correspondingly lower gm.
Datasheet of J438 still downloadable from Digikey Access Denied
Datasheet of J438 still downloadable from Digikey Access Denied
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