ZM, In the iteration I got from you, J101, J102, J103 and J104 are stuffed, 4 SMD per channel.
Can you please confirm that I have to add R114 and R110 ? I'm also building with IRFP150 at M102 and M103.
I was confused by the markings for the test above to mattattnet's question (he says 4 jfets. I don't know if that means 2 devices or 4 devices)
Thanks
Can you please confirm that I have to add R114 and R110 ? I'm also building with IRFP150 at M102 and M103.
I was confused by the markings for the test above to mattattnet's question (he says 4 jfets. I don't know if that means 2 devices or 4 devices)
Thanks
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Time to start building!
Have fun codyt! I'm about to start mine as well now that my Pearl 2 is finished. Just waiting on my Semisouths from jama via South America.
ZM, I may have gone too far. The Semisouths are SEJP120R063 or double die 120's. I've read through other posts they should behave as 120's just better dissipation. Any thoughts on changes needed for the circuit with these or just bang em in?
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frankly, I never look in data enough to compare these two, and get same conclusion as you .....
if claimed xconductance is double , comparing to 100 , then 60 is doubled
in any case, both are working swell in Babelfish
in fact , I can say - whichever SJEP you have, just toss it in - only don't mix them
if claimed xconductance is double , comparing to 100 , then 60 is doubled
in any case, both are working swell in Babelfish
in fact , I can say - whichever SJEP you have, just toss it in - only don't mix them
Time to start matching. I made up some 5x5mm pcbs from the very generous EUVL’s (Patrick) gerber files for miniature 2sk2145 breakout boards. I soldered one up with gate and source connected to a 100ohm RN55. 9 volt battery is ready to go, although I may try a 12v switcher I have laying around.
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you must wait for temp equilibrium - when reading is steady..... do not count time, look at display
no free lunch
I have fast socket thingie ........ and even with that , how fast you think that I'm doing batch of 50?
(having handy plate of Styrofoam , with 50 small holes in it)
ignore taster on thingie pic, later I put nice small relay and switch, so I can do other things while JFet is cooking, instead of keeping my finger on taster
edit- I'm testing proper Idss, no resistors in source or drain....... DMM connected as mAmeter in drain
no free lunch
I have fast socket thingie ........ and even with that , how fast you think that I'm doing batch of 50?
(having handy plate of Styrofoam , with 50 small holes in it)
ignore taster on thingie pic, later I put nice small relay and switch, so I can do other things while JFet is cooking, instead of keeping my finger on taster
edit- I'm testing proper Idss, no resistors in source or drain....... DMM connected as mAmeter in drain
Attachments
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If you've got good equipment of know quality (eg Fluke, Keysight Lab Bench Meters) it's easier just using the meter, and the accuracy is good enough.
If you've got a cheap crap multimeter of unknown quality then use a good current sense resistor.
I have decent tools, so I use a meter, same as ZM.
If you've got a cheap crap multimeter of unknown quality then use a good current sense resistor.
I have decent tools, so I use a meter, same as ZM.