I happen to agree
Not the perfect choise
But all we really need is a curcuit safe enough to power up
It just have to work without burning
THEN we can talk about perfecting it further
And we may have to realise it may still burn eventually
I wouldnt leave it out of my sight fore quite a while
I suppose its name of the game
Lets just build it, and talk later
Not the perfect choise
But all we really need is a curcuit safe enough to power up
It just have to work without burning
THEN we can talk about perfecting it further
And we may have to realise it may still burn eventually
I wouldnt leave it out of my sight fore quite a while
I suppose its name of the game
Lets just build it, and talk later
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Hello
For me it does not make sense to change the orig design JET to V fet .Even Juma first draw for the higher power rail with JET now when all design done why should I trow it out all on the window and start again something copletly different ?
Thank you any way .
I go with out cascode .
I have the layout for that to .
Thanks one more time guys , it was kind to read your advise ! I have no need more these type of help.
Greets
For me it does not make sense to change the orig design JET to V fet .Even Juma first draw for the higher power rail with JET now when all design done why should I trow it out all on the window and start again something copletly different ?
Thank you any way .
I go with out cascode .
I have the layout for that to .
Thanks one more time guys , it was kind to read your advise ! I have no need more these type of help.
Greets
Gab,
Your board does not make a lot of sense. You have these two rails coming out from center going left and right. They have two parallel lines connected by angles that look like mountains. If this is single sided... then you have simply created a plane going to the left and a plane to the right. So are the mountains just for looks or what is the point? Do you have any kind of silkscreen so we can see what you are trying to do? The schematic along with that board is not going to help a lot except that we can guess easily which are mosfets and which are resistors going to mosfets. Other than that its a bit confusing. Just to be clear I have no intention of diagnosing your FX-5 circuit as it is beyond me, but I am pretty sure that board is either designed for looks, making it confusing, or designed wrong.
Uriah
Your board does not make a lot of sense. You have these two rails coming out from center going left and right. They have two parallel lines connected by angles that look like mountains. If this is single sided... then you have simply created a plane going to the left and a plane to the right. So are the mountains just for looks or what is the point? Do you have any kind of silkscreen so we can see what you are trying to do? The schematic along with that board is not going to help a lot except that we can guess easily which are mosfets and which are resistors going to mosfets. Other than that its a bit confusing. Just to be clear I have no intention of diagnosing your FX-5 circuit as it is beyond me, but I am pretty sure that board is either designed for looks, making it confusing, or designed wrong.
Uriah
The fun of that story is that the regular F5 is a very good sounding proven design 100% warranted very simple to build without any headache.
Aren't you simply curious to listen to it?
Or are you smarter than Papa?
Not to forget that a distortion analyser should be helpfull to tweak the mods.
Aren't you simply curious to listen to it?
Or are you smarter than Papa?
Not to forget that a distortion analyser should be helpfull to tweak the mods.
What does concern me is that this whole matter regarding an up-rated F5 should have been split from the main F5 thread very early on.
To attempt to find anything regarding the F5 - as originally gifted by Nelson Pass - is like looking for a needle in a haystack....a haystack of almost 6000 postings!
To attempt to find anything regarding the F5 - as originally gifted by Nelson Pass - is like looking for a needle in a haystack....a haystack of almost 6000 postings!
Hello
The board was design by hand , there is no silkscreen unfortunately .
Sorry about that . The reason I wrote I want to stick the orig design !It take me hours to draw a layout like these by hand .
These is not a SECRET or something I just don't have any silkscreen .
You can find the schematic in the last couple page if you seriously interested .
For me it make sense , I DESIGN many working boards like these with out any software . And always work out fine .
I posted the cascoded the input before .But I will posted one more time and also the full schematic .
My orig question was : The cascode was design to 40V rail , now I go with lower voltage actually 24V rail .So if I want the cascode to work fine do I have to use lower value resistor to connect the cascode to the rail and to the ground or to the JET source.
Greets
The board was design by hand , there is no silkscreen unfortunately .
Sorry about that . The reason I wrote I want to stick the orig design !It take me hours to draw a layout like these by hand .
These is not a SECRET or something I just don't have any silkscreen .
You can find the schematic in the last couple page if you seriously interested .
For me it make sense , I DESIGN many working boards like these with out any software . And always work out fine .
I posted the cascoded the input before .But I will posted one more time and also the full schematic .
My orig question was : The cascode was design to 40V rail , now I go with lower voltage actually 24V rail .So if I want the cascode to work fine do I have to use lower value resistor to connect the cascode to the rail and to the ground or to the JET source.
Greets
Attachments
No I'm not smarter than Papa !!! No one said or think that !!!! Never ever , at least not ME!!
AL MY RESPECT TO Mr PASS!!!
I have a something similar design so now I would like to try to X-ed . Nothing wrong with the orig design .
Million thank to Mr Pass to share with us such a great amp .
Yes you right we who want high power F5 or XF5 we should start a new tread .
But you always find information about the original (well design and great amp) if you go back at least 100 page .
Sorry about that .
Greets
AL MY RESPECT TO Mr PASS!!!
I have a something similar design so now I would like to try to X-ed . Nothing wrong with the orig design .
Million thank to Mr Pass to share with us such a great amp .
Yes you right we who want high power F5 or XF5 we should start a new tread .
But you always find information about the original (well design and great amp) if you go back at least 100 page .
Sorry about that .
Greets
Udailey,
I don't think that was directed at you, others were much more harsh in their remanding than you!
Ron
learn to read.
The suggestion in the post said Vgrade jFET. It did not say Vfet nor JET.
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You may want to consider using V grade jFETs to give more current capability to drive the load capacitance and the lower Gm of the Laterals. This may require the cascode voltage to be altered to bring the Vgrade temp back down to acceptable levels.[/QUOTE]
Sorry about Andrew I didn't saw the "j" before the FET .
How Juma said your advise is great , I agree but if is JET or FET there is no base .
Probably he thought abut the original drawing were the cascode uses BJT .
A bit I got confused!
--------------------------------------------------------------------------
Posted by JUMA
Exactly! V grade JFETS are better solution here and resistors in voltage divider should be something like 4k7 from base to rail and 2k7 from base to ground.
--------------------------------------------------------------------------
Any way thank you very much , there is no hard feelings what so ever !
God bless you
I want to learn from you guys !
Greets
Sorry about Andrew I didn't saw the "j" before the FET .
How Juma said your advise is great , I agree but if is JET or FET there is no base .
Probably he thought abut the original drawing were the cascode uses BJT .
A bit I got confused!
--------------------------------------------------------------------------
Posted by JUMA
Exactly! V grade JFETS are better solution here and resistors in voltage divider should be something like 4k7 from base to rail and 2k7 from base to ground.
--------------------------------------------------------------------------
Any way thank you very much , there is no hard feelings what so ever !
God bless you
I want to learn from you guys !
Greets
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Thanks
Udailey, I first read your post AFTER my own post
My post wasnt really aimed at anyone in particular, not at all
Just a general heads up to keep a good tone
I think its important especially here
Too much to loose
Seperate threads, sure
But it wont make anything any easier at all
Probably just even more difficult to find information
Or there may not be any information to find
But sure, we have to control ourselves
Or it will be a mess
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Just a general heads up to keep a good tone
I think its important especially here
Too much to loose[/QUOTE]
I agree and support these .
We must learn from each-other and try to give our best or nothing in that "case".
There is not one person who know everything or was born with the F5 .
We should always ask from expert guys someone wrote these !
Greets
I think its important especially here
Too much to loose[/QUOTE]
I agree and support these .
We must learn from each-other and try to give our best or nothing in that "case".
There is not one person who know everything or was born with the F5 .
We should always ask from expert guys someone wrote these !
Greets
I think it is far too late now for anyone to separate these posts; however it is something to be borne in mind in the future.
Are you dyslexic ? What is JET ?
JFETs are amplifying devices, BJTs are cascoding devices and they have base.
I'm afraid you can not be helped further, you disregard good advices or you interpret them wrongly, so as far as I'm concerned, you are on your own.
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