think i will invest in a sot-23 test jig for my dca75
and see if i can get hold of a batch off the reel instead of individual ones hopefully consistent idss then
and see if i can get hold of a batch off the reel instead of individual ones hopefully consistent idss then
Why not. Since we saw they emulate a K170BL well for main parameters. About absolute noise profile and its level not sure but they should be close again.
the 2 fets i used for the double where picked at random
i wonder if you balance the 2 would that make a difference to the noise
i have noticed when you parallel the fets that get the exact sum of the 2 fets 2.4 + 3.2 = 5.6
i wonder if you balance the 2 would that make a difference to the noise
i have noticed when you parallel the fets that get the exact sum of the 2 fets 2.4 + 3.2 = 5.6
They should be sharing Id current and dissipation better equally when chosen more Idss balanced to pair.
P.S.
DCA tester only uses 3V VDS so expect little more IDSS and gfs when 10V tested as per Toshiba datasheets.
P.S.
DCA tester only uses 3V VDS so expect little more IDSS and gfs when 10V tested as per Toshiba datasheets.
To fully double gfs maybe you need four in parallel but that would be like trying to chase a 2SK369BL
Using the 4 matches i made up a B1 buffer with a Alps black beauty 20K pot,
regulated supply lm317 & lm337 @ 10v dc
playing radio on computer though Khadas tone board dac to 2x 50w ice power amp
sounds very good 😀 indeed
20201128_212134 by glenn jarrett, on Flickr
20201129_122045 by glenn jarrett, on Flickr
20201129_122053 by glenn jarrett, on Flickr
regulated supply lm317 & lm337 @ 10v dc
playing radio on computer though Khadas tone board dac to 2x 50w ice power amp
sounds very good 😀 indeed
20201128_212134 by glenn jarrett, on Flickr20201129_122045 by glenn jarrett, on Flickr20201129_122053 by glenn jarrett, on Flickr
Hi.Does not it need cooler on 2sk209gr jfets? It is because aluminium smd jfet cooler is suggested by people.Could you measure temperature on jfets with IR thermometer? Regards
Hi
my bench is 22c and the fets the highest reading i could get was 30c
if dissipation is a problem can we not just encapsulate both fets with miliput as in pic
its that hard when dry you can drill and tap it !
20201129_135825 by glenn jarrett, on Flickr
my bench is 22c and the fets the highest reading i could get was 30c
if dissipation is a problem can we not just encapsulate both fets with miliput as in pic
its that hard when dry you can drill and tap it !
20201129_135825 by glenn jarrett, on Flickr
Hi.Milliput is an interesting idea! It prevents the chips and also helps cooling too? I was thinking wrapping multi wire thin copper around fets but 30C is not a problem IMHO.I do not know why people put smd coolers on them.(it sometimes reaches 38C here in Istanbul in summer and we should consider putting them in a box and it will be hotter than free air then)
I also ordered same pcbs from Aliexp and will try as soon as i get pcbs.Now i need a sot23 adapter to match them.(yours seems a good choice but it seems a bit expensive) Regards Umit
I also ordered same pcbs from Aliexp and will try as soon as i get pcbs.Now i need a sot23 adapter to match them.(yours seems a good choice but it seems a bit expensive) Regards Umit
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