Time is due for another update :
Main Amp PCB & Regulator PCB
The Gerber files have been all checked and sent to Variac for prototyping. I do not have a date as to when they will arrive. The 10 sets of proto PCBs will go to the 3 test team members for testing when available.
Regulator MOSFET GB
I have heard from ZhouFang. He knows what needs sending to where. I do not have a date when that will happen. Patience required. Nothing much else I can do there.
Resistor GB
Is progressing well. We have ordered the resistors. They will arrive soon enough, and will be shipped to the matchers mid June. Full marks to the GB leader (Horio).
The match team has already received matching instructions from me, and are preapring for the required matching hardware. Many interesting discussions and inputs there.
Case GB
Mark is waiting for a few small parts before he can confirm total weight and hence bulk shipment cost. Because there are only 3 subscribers in Asian, they will receive their parts directly from us. Only when there is a cost advantage will we ship in bulk (to US and Austria).
We shall ask for the down payment only when all the info are available.
John has a quote on hand for the 25 pairs fully machined Conrad heatsinks. We still need to clarify a few points with Conrad. So I expect you would know more in the next week or two.
Test Team
The test team has already their test tasks distributed. Dave is busy preparing the bills of material for the many configurations. Once that is done, the test team will proceed with the test plan. We shall publish the results in stages, after each test stage has been fully completed and we are satisfied with the results.
So much for now,
Patrick
.
Main Amp PCB & Regulator PCB
The Gerber files have been all checked and sent to Variac for prototyping. I do not have a date as to when they will arrive. The 10 sets of proto PCBs will go to the 3 test team members for testing when available.
Regulator MOSFET GB
I have heard from ZhouFang. He knows what needs sending to where. I do not have a date when that will happen. Patience required. Nothing much else I can do there.
Resistor GB
Is progressing well. We have ordered the resistors. They will arrive soon enough, and will be shipped to the matchers mid June. Full marks to the GB leader (Horio).
The match team has already received matching instructions from me, and are preapring for the required matching hardware. Many interesting discussions and inputs there.
Case GB
Mark is waiting for a few small parts before he can confirm total weight and hence bulk shipment cost. Because there are only 3 subscribers in Asian, they will receive their parts directly from us. Only when there is a cost advantage will we ship in bulk (to US and Austria).
We shall ask for the down payment only when all the info are available.
John has a quote on hand for the 25 pairs fully machined Conrad heatsinks. We still need to clarify a few points with Conrad. So I expect you would know more in the next week or two.
Test Team
The test team has already their test tasks distributed. Dave is busy preparing the bills of material for the many configurations. Once that is done, the test team will proceed with the test plan. We shall publish the results in stages, after each test stage has been fully completed and we are satisfied with the results.
So much for now,
Patrick
.
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EUVL,
I'm on the "case list" for the U.S GB. I've ordered and paid for the resistor GB.
Will heatsinks be part of the "case list", or will that be a separate GB (or individual buy)?
I'm assuming there will be a PCB buy (from you?) after testing and prototyping, true?
WIll there be a GB for the matched semiconductors, other resistors, etc?
Now that I've risen to the lists to get a case, I just want to make certain I have not forgotten any other parts/materials/transformer lists I ought to be on, to get together most of my components.
Thanks, EUVL, for spearheading this overall effort. With everything else on your plate, I can imagine how busy you are.....
Ken
P.S. Curse you, Papa Pass--my completion of your outstanding "standard F5" has given me (and my wallet) the audiophile flu once again..... And thank you for that illness....it truly is contagious.....!!!!
I'm on the "case list" for the U.S GB. I've ordered and paid for the resistor GB.
Will heatsinks be part of the "case list", or will that be a separate GB (or individual buy)?
I'm assuming there will be a PCB buy (from you?) after testing and prototyping, true?
WIll there be a GB for the matched semiconductors, other resistors, etc?
Now that I've risen to the lists to get a case, I just want to make certain I have not forgotten any other parts/materials/transformer lists I ought to be on, to get together most of my components.
Thanks, EUVL, for spearheading this overall effort. With everything else on your plate, I can imagine how busy you are.....
Ken
P.S. Curse you, Papa Pass--my completion of your outstanding "standard F5" has given me (and my wallet) the audiophile flu once again..... And thank you for that illness....it truly is contagious.....!!!!
> Will heatsinks be part of the "case list", or will that be a separate GB (or individual buy)?
The people who have subscribed for the case will get a quote for the heat sink as well.
John is arranging that directly with Conrad, so that you get the best deal possible.
Only those subscribers will be taken care of by the GB action by John.
> I'm assuming there will be a PCB buy (from you?) after testing and prototyping, true?
No, the main amp PCB and the PSU PCB will be directly available from the DIYA shop in unlimited quantities, after testing.
> WIll there be a GB for the matched semiconductors, other resistors, etc?
That is up to you to organise.
> Now that I've risen to the lists to get a case, I just want to make certain I have not forgotten any other parts/materials/transformer lists I ought to be on, to get together most of my components.
These will follow as many of the 25 subscribers will have the same need.
And one tester will certainly show the way.
> With everything else on your plate, I can imagine how busy you are.....
You have no idea how busy I am at work, making a living to make this possible in the first place !!
And you also have no idea what I have in the pipe .....
Patrick
The people who have subscribed for the case will get a quote for the heat sink as well.
John is arranging that directly with Conrad, so that you get the best deal possible.
Only those subscribers will be taken care of by the GB action by John.
> I'm assuming there will be a PCB buy (from you?) after testing and prototyping, true?
No, the main amp PCB and the PSU PCB will be directly available from the DIYA shop in unlimited quantities, after testing.
> WIll there be a GB for the matched semiconductors, other resistors, etc?
That is up to you to organise.
> Now that I've risen to the lists to get a case, I just want to make certain I have not forgotten any other parts/materials/transformer lists I ought to be on, to get together most of my components.
These will follow as many of the 25 subscribers will have the same need.
And one tester will certainly show the way.
> With everything else on your plate, I can imagine how busy you are.....
You have no idea how busy I am at work, making a living to make this possible in the first place !!
And you also have no idea what I have in the pipe .....
Patrick
Sounds interesting...organic or crystalline?
I have 16 pair of Toshiba 2SK3497/2SJ618 in the US if I can be of assistance to your group.
Patrick
It Is a better way to collect parts for this project In many steps and not at one time because of the high price
still there are no official schematics
so can you please confirm that your F5X will use Toshiba 1530/201 as output devices and not some other pairs and 2SK3497/2SJ618 as regulator devices so I can purchase
It Is a better way to collect parts for this project In many steps and not at one time because of the high price
still there are no official schematics
so can you please confirm that your F5X will use Toshiba 1530/201 as output devices and not some other pairs and 2SK3497/2SJ618 as regulator devices so I can purchase
> so can you please confirm that your F5X will use Toshiba 1530/201 as output devices and not some other pairs
Yes. And frontend JFETs will be 2SK170BL (Idss about 7mA) and 2SJ74BL (about Idss 7.8mA).
> and 2SK3497/2SJ618 as regulator devices
Correct, if you choose to use a regulator of my design.
Patrick
Yes. And frontend JFETs will be 2SK170BL (Idss about 7mA) and 2SJ74BL (about Idss 7.8mA).
> and 2SK3497/2SJ618 as regulator devices
Correct, if you choose to use a regulator of my design.
Patrick
wow with Idss specs like that , many are going to be very disappointed . while i'm sure that the 25 or so initial will be able to come up with them ......
i'm trying to find some time tonite to sort , but out of 30 j74's only 2 are in that range . most are coming up in the 9's with some 8's and 10's .
i haven't even started with my k170's 'cept for a few which are in the 8's
cheers Woody
Is the difference in Idss for the "degeneration trick". If so, are you going to make the changes to resistors too?
I know I had a heck of a time finding an Octet with the "degeneration trick" match. Two Quads are more attainable.
I think somewhere back in the thread Patrick mentions the Idss should be about 10% higher for th P JFET. It is not that they need exactly 7mA and 7.8mA Idss, but that with typical devices the 10% ratio difference would be the typical "Trick" values.
Some experimenting could prove this to be slightly different with the devices you have, or end up with. But, you are no doubt closer to the designed targets using these values.
Some experimenting could prove this to be slightly different with the devices you have, or end up with. But, you are no doubt closer to the designed targets using these values.
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You can use any values of Idss for the JFETs as long as P-P and N-N are matched, and the P-JFET has the same bias current after the 5R degeneration.
It works out to be about 0.8mA more than the N-JFET. I have to publish a default value, so I choose the same as NP, at around 7mA.
So if you have 2SJ74s at say 9mA, you want to find a pair of 2SK170s with about 8.2mA.
The exact formula for calculating this has been published before.
I am in a rush to leave home now, so if someone could kindly dig it up for me please.
Patrick
It works out to be about 0.8mA more than the N-JFET. I have to publish a default value, so I choose the same as NP, at around 7mA.
So if you have 2SJ74s at say 9mA, you want to find a pair of 2SK170s with about 8.2mA.
The exact formula for calculating this has been published before.
I am in a rush to leave home now, so if someone could kindly dig it up for me please.
Patrick
Quoting from EUVL:
"If you use the 5R degeneration on the 2SJ74, as I recommended, then you can calculate the Idss of the 2SJ74's using the following equation :
Idss (2SJ74) = Id * (1 + Rs.Yfs)
where Id = Idss of the 2SK170 in this case; Rs =5.1R; Yfs = 0.033 S for 2SJ74 at that bias range.
It works out to roughly 1mA higher than the Idss of the 2SK170s.
Get matched quads for both K170s and J74s if you can, so that both left and right channels are the identical.
Guido
"If you use the 5R degeneration on the 2SJ74, as I recommended, then you can calculate the Idss of the 2SJ74's using the following equation :
Idss (2SJ74) = Id * (1 + Rs.Yfs)
where Id = Idss of the 2SK170 in this case; Rs =5.1R; Yfs = 0.033 S for 2SJ74 at that bias range.
It works out to roughly 1mA higher than the Idss of the 2SK170s.
Get matched quads for both K170s and J74s if you can, so that both left and right channels are the identical.
Guido
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