Hello,
on the circuit on page 2 here:
http://www.firstwatt.com/pdf/art_diy_sony_vfet_1st_draft.pdf
r13 is 2.21k but r14 is 2.2k, should they have same value? 2.21k?
Q7 is irf "no p" 240 and Q8 is irfp9240, both with "p" right?
can r1 be 2.21k? Easier shopping list..
Thank`s
on the circuit on page 2 here:
http://www.firstwatt.com/pdf/art_diy_sony_vfet_1st_draft.pdf
r13 is 2.21k but r14 is 2.2k, should they have same value? 2.21k?
Q7 is irf "no p" 240 and Q8 is irfp9240, both with "p" right?
can r1 be 2.21k? Easier shopping list..
Thank`s
To confirm for other Canadian's. UPS ground may hide USPS Priority because the system thinks they are the same "class", and will only suggest the cheaper one. If you would ever like USPS Priority please email contact@diyaudiostore.com and we'll be able to access it for you.
I ordered both the 2.21K and the 2.2K but the difference is so slight I would not fret using a 2.21K for the 2.2K. A 5% 2.21K could easily be 2.2K even though I use 1% resistors but 5% would do I am sure.
IRFP240 is the other answer I am almost positive. It is what I am using.
I see that in the bom posted the "B" type of the TL431 were used..
In the AL-boards GB that TeaBag ran earlier, he wrote:
"TL431ACLPR - Buy extra, if something will short, it will likely be these that die. The TL431B were found not to work well. Use "A" type."
I don`t know if this applies here as well, or what the problem was..just thought i would give notice..
In the AL-boards GB that TeaBag ran earlier, he wrote:
"TL431ACLPR - Buy extra, if something will short, it will likely be these that die. The TL431B were found not to work well. Use "A" type."
I don`t know if this applies here as well, or what the problem was..just thought i would give notice..
That was me, We had issues with oscillations with the B grade. The A worked fine. In hindsight it may be that since we had increased the capacitance to 470uF, to slow down the turn on surge, that is the issue. I see that Nelson took it the other way and reduced the bias capacitance to make it come up faster.
Anyway, I have been running this for over 6 months and it sounds wonderful.
No, but they will starting tomorrow. I was waiting to see how many kits were left after the dust had settled, before deciding how to handle allocating them properly.
Most people took their full allocation for Group 1, and there are now only 20 kits left for 60 people left the wait list. I'm going to start contacting people in Group 2 in order of their signup date, starting tomorrow.
Apologies to anyone who missed out on this batch. I believe there will be enough in batch 2 to go around to everyone who missed out.
As soon as we know the total number of VFETs available we'll offer them for immediately pre-sale. Preference will go to those in Group 1 who gave up their spots, and then those in Group 2 who missed out. Batch 2 should go on sale in about a week from now, and will ship in around 3 months time.
Now that we know all the prices (kit and shipping), we can do an easy and simple pre-sale of the next batch. This can happen immediately once we know the total number of matched VFETs Nelson can make available.
We learned a lot from this experience, and the next one will be better planned with less nail biting. Thanks for your patience with the process.
Appreciated! However I'm just facilitating
All thanks should really just go to Nelson who is heart and soul of this operation.I'm sure I'm missing more than a few things here but - Nelson had the insight to buy the VFETs, designed and prototyped the circuits, wrote the articles, designed and tested the bracket, designed the board especially for DIYers to make it easy to test, prototyped the whole thing using the readily available Deluxe 4U chassis/UMS heatsink so it would be that much easier for DIYers to complete, wrote the build notes, painstakingly hand-matched and sequentially arranged over 1,000 VFETS, and last but not least made these rare parts available at both a very economical price, and in a way that would ensure the most DIYers possible would have a chance to (successfully) build it. Calling that a legendary effort would be an understatement
Appreciated! However I'm just facilitating
I'm sure I'm missing more than a few things here but - Nelson had the insight to buy the VFETs, designed and prototyped the circuits, wrote the articles, designed and tested the bracket, designed the board especially for DIYers to make it easy to test, prototyped the whole thing using the readily available Deluxe 4U chassis/UMS heatsink so it would be that much easier for DIYers to complete, wrote the build notes, painstakingly hand-matched and sequentially arranged over 1,000 VFETS, and last but not least made these rare parts available at both a very economical price, and in a way that would ensure the most DIYers possible would have a chance to (successfully) build it. Calling that a legendary effort would be an understatement
I suppose that after a few decades of comercial success it is much more rewarding to do such endeavors!
Thank you Mr. Nelson Pass for giving so much to the community!!!
Currently preparing more tested pairs using biological neural networks in
meditation mode with Thievery Corp playing in background.
Drives 2005 Freestyle.
Still trying to decide allowance for blown up devices.
Any finished builds yet? How about pictures?
I am building. I worked on my case last week. I bought the heatsinks almost a year ago for this build. It is what is called redneck engineering in the deep south but it will be functional. I should start stuffing boards next week.
I am putting the V-fets on top of the brace per the V-fet #1 article with the board on the underside of the brace. I believe this is the correct way. The brace is wider on one side that the the other. Does anyone know which side goes up. I figured I will figure it out from the pinouts of the V-fets and traces on the boards if no one speaks up. Being that the pins of the V-fets only line up one way it should be easy enough figuring it out. But advice and experience is always welcome.
I am putting the V-fets on top of the brace per the V-fet #1 article with the board on the underside of the brace. I believe this is the correct way. The brace is wider on one side that the the other. Does anyone know which side goes up. I figured I will figure it out from the pinouts of the V-fets and traces on the boards if no one speaks up. Being that the pins of the V-fets only line up one way it should be easy enough figuring it out. But advice and experience is always welcome.