Entirely missing the point
No degree of execution will allow for proper control of ground currents if the pcb utilises a ground plane instead of a proper star ground. Even companies like Sony resist the lazy approach in their slightly more upmarket products as can be seen from the attached picture. There is a thick copper bar connecting the two stars on the component side.
Similar attention to PS distribution also yields sonic benefits. This may not be so important in Sony's dac, but in a high gain phono pre can make or break the circuit.
No degree of execution will allow for proper control of ground currents if the pcb utilises a ground plane instead of a proper star ground. Even companies like Sony resist the lazy approach in their slightly more upmarket products as can be seen from the attached picture. There is a thick copper bar connecting the two stars on the component side.
Similar attention to PS distribution also yields sonic benefits. This may not be so important in Sony's dac, but in a high gain phono pre can make or break the circuit.
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Just stile of post that criticize the paradise and came up with no alternatives
this is missing the point
Please don't quote me any more you are not the kind of person I like to have any sort of dialog especialy after your tantrums of earlier on in the tread.
You are back in ignore bin till you post your PCB version.
this is missing the point
Please don't quote me any more you are not the kind of person I like to have any sort of dialog especialy after your tantrums of earlier on in the tread.
You are back in ignore bin till you post your PCB version.
About to start transistor testing with the circuit from Hesener. Does the power supply need to be shut off when removing and installing the transistor under test, or is "hot swapping" safe?
Lads
Just I have changed Q 90 and Q 99 no difference ,
previously I have measured 2SK 170 as Bksabath has suggested
K 170= 10,5 mA / J 310 not possible to measure so.
what for a fu..... is that, whatever for now I must pick up my son
from Dublin airport, tomorrow is a new day
So long Werner
K170 at 10.5 mA seems way too high.... please try with 7mA
Measure J310 Idss and choose the highest you can get.
Measure J310 Idss and choose the highest you can get.
Hi Ricardo
I have only one K 170 with 8,5 mA I try tomorrow morning
And how I can measure J310 ????? I have to drive, sorry for that
Werner
J310 Data sheet pdf - JFET VHF/UHF Amplifiers - ON Semiconductor
Cek pin out and IDss on data sheets
More details about testing
Transistor matching
If you touch the J fet the current will go up as the J fet get warmer
If your socks sparkle in the dark when you take them off
Wenn Ihre Socken funkeln in der Dunkelheit, wenn Sie sie ausziehen you are in bad troubles😀
Sound like a joke but is not as that is sign of electrostatic charge which kill the Jfets use same precautions
Cek pin out and IDss on data sheets
More details about testing
Transistor matching
If you touch the J fet the current will go up as the J fet get warmer
If your socks sparkle in the dark when you take them off
Wenn Ihre Socken funkeln in der Dunkelheit, wenn Sie sie ausziehen you are in bad troubles😀
Sound like a joke but is not as that is sign of electrostatic charge which kill the Jfets use same precautions
😀
Believe me,
he's aware of that.
B.T.W.:
You're really multifunctional in terms of foreign languages. 😎
Goggle translate helps when is not Italian basic Spanish and English with spelling mistakes for later.
Yes most probably but don't forget there are 200 + builds out there and that joke is best way to make it stick especially when dealing with precious 2SK170 or 2SJ74.
Mea Culpa mea maxima culpa...
Yes most probably but don't forget there are 200 + builds out there and that joke is best way to make it stick especially when dealing with precious 2SK170 or 2SJ74.
Mea Culpa mea maxima culpa...
Any thing more than 10 🙂 More seriously, any normal function 327/337 will do (Hfe 250 ... and up). One of the things I am concerned about is to much gain in there, not to little ...
If you AC couple/10us on scope probing +V input connector to GND in and -V input connector to GND in what do you see? If you then put 10nF across +Vin to GND what you see again?
I was thinking and (maybe is way out I know and sorry) wuld it be posiisble to trim either R13 or R15 to reduce the ofset and take same of the work load of the servo.
And also what level of matcing is required on the Jfets both interstage and between stages.
Never ever going to go near one of those again...😉
Just sintetic materials and wool + walking on floor boards can give you nasty Zap
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Hi Ungie,
one of the wise guys told us, some posts ago,
the input doublequad should be rather high (~450?)
those mediocres just have to be matched as long as
they reach >200.
Right ?
