Well, there was a first fired up.
Now I put in IRFP250, because of peace.
As I slowly raised PSU voltages, there were some smoke, I think from one of the source resistors. Of course I have switched off immediately.
Nothing bad happened, there were remained enough magical smoke in parts.
Lesson learned:
It is quite easy to emerge the quiscent current to the blody hell, espacially with 0.1 Ohm source resistors.
Now I put in IRFP250, because of peace.
As I slowly raised PSU voltages, there were some smoke, I think from one of the source resistors. Of course I have switched off immediately.
Nothing bad happened, there were remained enough magical smoke in parts.
Lesson learned:
It is quite easy to emerge the quiscent current to the blody hell, espacially with 0.1 Ohm source resistors.
They don't speak about MP821 series:
"Without a Heat Sink: When in free air at +25°C the MP Series have the following power ratings: MP915: 1.25W MP916, MP925, MP930: 2.25W; MP2060: 2.5W MP9100: 3.5W"
However it seems to me, heatsink is a must in this case.
(It is enough to touch them.)
"Without a Heat Sink: When in free air at +25°C the MP Series have the following power ratings: MP915: 1.25W MP916, MP925, MP930: 2.25W; MP2060: 2.5W MP9100: 3.5W"
However it seems to me, heatsink is a must in this case.
(It is enough to touch them.)
It is difficult to me because of English.
Apart from this, it is difficult to describe.
Here is a picture:
https://onedrive.live.com/redir?res...74&authkey=!9!rkr!r0TZw$&v=3&ithint=photo,jpg
Apart from this, it is difficult to describe.
Here is a picture:
https://onedrive.live.com/redir?res...74&authkey=!9!rkr!r0TZw$&v=3&ithint=photo,jpg
Attachments
Well, I will try.
First of all, it seems to me as if the musicians would playing slower, as I listen this F6.
This is obviously an illusion.
Perhaps because there are more little details, and as they lined up on the time axis, it seems will be longer.
Secondly, sounds are more rounded, it does not mean that there are less treble, but somehow more reassuring.
Now I compared it to my DIY J2.
F6 now playing with Fairchild IRFP250s.
There was an accident.
On one of the channels hasn't been possible to set up quiescent current. It turned out, it was because source leg of Q2 hasn't connected securely. And as I measured voltage on it, because pressure of measuring pin suddenly connect it to its place. Of course quiescent current trimmer was set on maximum, so there were some smoke. And I was lose two excellent IRFP250s and one Caddock 821. Sigh...
But, if it happens with Semis, so I certainly executed myself by seppuku.
First of all, it seems to me as if the musicians would playing slower, as I listen this F6.
This is obviously an illusion.
Perhaps because there are more little details, and as they lined up on the time axis, it seems will be longer.
Secondly, sounds are more rounded, it does not mean that there are less treble, but somehow more reassuring.
Now I compared it to my DIY J2.
F6 now playing with Fairchild IRFP250s.
There was an accident.
On one of the channels hasn't been possible to set up quiescent current. It turned out, it was because source leg of Q2 hasn't connected securely. And as I measured voltage on it, because pressure of measuring pin suddenly connect it to its place. Of course quiescent current trimmer was set on maximum, so there were some smoke. And I was lose two excellent IRFP250s and one Caddock 821. Sigh...
But, if it happens with Semis, so I certainly executed myself by seppuku.
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