3rd list
Have the emails gone out to the people on the list for the 3rd release? I've not had an email and worried something has gone wrong.
Have the emails gone out to the people on the list for the 3rd release? I've not had an email and worried something has gone wrong.
same question here - it was Feb 6th in the announcement. Anyone have any update?
C1,2 are 470 uF ah ok 🙂
I do not build Vfet part2 with Diy Sony Vfet article components values 😀
Have fun
Sorry to bother with a question that I know has been handled, I just can't find it.
Which pairs of semiconductors, in this amp, need to be matched?
I just started assembling my 6 channels and no mistakes with resistors and trimmers were found 🙂
I was at first a bit disappointed with the boards. First one I looked like it had an offset in the solder resist. But the other 5 were quite fine and the layout is very clear!
No big risk of making mistakes, also the boards are of good quality.
I will make one amp with the expensive Italian brackets and the rest with own brackets.
If anyone needs some 50x50x5mm aluminium L profile I have a few meters extra 🙂
Anyway I will soon solder in the JFETs and drivers and see what happens 🙂
Which pairs of semiconductors, in this amp, need to be matched?
I just started assembling my 6 channels and no mistakes with resistors and trimmers were found 🙂
I was at first a bit disappointed with the boards. First one I looked like it had an offset in the solder resist. But the other 5 were quite fine and the layout is very clear!
No big risk of making mistakes, also the boards are of good quality.
I will make one amp with the expensive Italian brackets and the rest with own brackets.
If anyone needs some 50x50x5mm aluminium L profile I have a few meters extra 🙂
Anyway I will soon solder in the JFETs and drivers and see what happens 🙂
Is it normal after setting the offset at T18 to aprox 30mv for it to rise back to 1.7v after sitting off over night? No Vfets yet.
I think it's quite normal.
You can reset it to normal value, when Q5-Q6 reach its temperature equilibrium.
If you have about +-50mV at T18 it is O.K.
You can reset it to normal value, when Q5-Q6 reach its temperature equilibrium.
If you have about +-50mV at T18 it is O.K.
Are your 2SK170/2SJ74 genuine Toshiba or Linear Systems parts?
If not, it can be terrible sucks.
If not, it can be terrible sucks.
Basically none. We did match parts in the kits where possible to keep
people happy, but unless you are paralleling the VFETs, there are adjustments
to accommodate differences between parts.
It's done. She's a beauty. But it's too late o'clock, so I'll have to wait until tomorrow to fire her up. A great man once said "Check everything twice, once in the evening and once in the morning.", and that's what I'll do. I don't wanna to let out that magic VFET smoke due to some silly wiring mistake tired me couldn't spot 🙂
Attachments
@ Rodeodave
If start up with variac voltage slide time not more 5s.
Amazing Goood Work
Greetings
If start up with variac voltage slide time not more 5s.
Amazing Goood Work
Greetings
Mr Pass,
The following quote was taken from your Burning Amp part 3 article:
"The 2SJ313 and 2SK2013 are still available, and you can use them or substitute other Mosfets, such as the Fairchild FQP3N30 and FQP3P20. The Vgs of the Toshibas is about 2
volts. Some of the alternatives will be in the region of 4 volts or so, requiring a higher value for P1 and P2, probably 1K ohm."
Your schematics of the VFET amps show the 2SK2013/2SJ313, but the Suplemental Kit from the diyaudio store includes the Fairchilds.
If one uses the KIT's Fairchilds would you advice (as you did with the Burning amp) changing the values of any other components?
The following quote was taken from your Burning Amp part 3 article:
"The 2SJ313 and 2SK2013 are still available, and you can use them or substitute other Mosfets, such as the Fairchild FQP3N30 and FQP3P20. The Vgs of the Toshibas is about 2
volts. Some of the alternatives will be in the region of 4 volts or so, requiring a higher value for P1 and P2, probably 1K ohm."
Your schematics of the VFET amps show the 2SK2013/2SJ313, but the Suplemental Kit from the diyaudio store includes the Fairchilds.
If one uses the KIT's Fairchilds would you advice (as you did with the Burning amp) changing the values of any other components?
Very nice build Rodeodave! Nice and compact.🙂
What are the 2 twisted pairs running over the transformer? Can't you hide those?
What are the 2 twisted pairs running over the transformer? Can't you hide those?
Thank you sir!
I was just thinking that nothing looks critical except for the input JFET pair maybe. But it is good if I do not need to match those, as I have pretty limited quantities of them.
I will, at this point, not parallel VFETs.
I think the best I have is some triplet that is matched, and for stereo I would need 2+2 triplets. Hmm...maybe double output devices would anyway be feasible 😀
Those of you who have built the amp with Fairchild driver FETs, have you actually needed to replace the 500ohm trimmer with a 1k one?
If so then I better not solder in anymore 500ohm. One pair of boards already has them.
