Those fets sure look like good ol' TO247 to me🙂 Not like those Lovoltechs in a weird house. But I guess they could be the ones underneath the flange?
Steen.
BTW Very nicely build😎
Steen.
BTW Very nicely build😎
steenoe said:
I think the good ol' TO247 IS good ol' IRFP240 - but look just above the RCA input socket in the top-down picture - three small legs going in under the heatsink, and a small nut on top......mabye it's the Jfet ??
Cheers !
Buhl
Yep, I think they are irfp240's too. If that is the case, the reviewer at 6 moons had it all wrong. Here is quoting from 6moons:
Steen🙂
The picture he reffers to is attached below😉 Either that, or NP did have them custom made😀 Those suspicious 3 legs underneath the flange is more likely the Jfet🙂
Steen🙂
Attachments
SMathews said:One Mosfet for CCS, one Mosfet for the Cascode, so what's the 3rd mosfet for
SMathews
The 3rd Mosfet is for Voltage Regulation like I said in another thread. Yes I'm 100% those 3 legs sticking out is that of the Jfet sandwiched between the pcb and the flange with the heatsink surface facing up of course.😎
I may be wrong, but doesn't the JFET sit under the PCB, not sandwiched between the heatsink and the PCB? I can see a cutout or hole in the PCB where the three legs are visible.
reviewer doesn't know the difference between a MOSFET and a JFET!
i suppose we can cut some slack to a non-DIYer 🙂
i suppose we can cut some slack to a non-DIYer 🙂
Trust me...these things are much, much smaller than a TO-247. They're about the size of your pinky fingernail. I haven't looked at these pictures, but from pictures I saw before I seem to recall that the JFET appeared to be sandwiched between the PC board and the heatsink flange--a stealth part.
Grey
Grey
Hi nice review,who did it, first off this product is pure class-a,
no doubt about!,i was expecting to hear good words about it
there has been no mention of how it sounded at all, i am disappointed because my pure class-a s sound like super sonics
I wish Mr Pass good luck in the field of pure A it would be a tough
field to compete in in the future
regards
no doubt about!,i was expecting to hear good words about it
there has been no mention of how it sounded at all, i am disappointed because my pure class-a s sound like super sonics
I wish Mr Pass good luck in the field of pure A it would be a tough
field to compete in in the future
regards
I guess we can😀 Especially one from 6Moons, who always puts up nice pic's of NP's amps and furthermore speaks nice about them🙂 For a second, I thought everybody is a DIY'er😀
Any chance to have e peek at those pic's?
Steen🙂
So Nelson just began producing class A amps? Hmmm...I guess all those class A Thresholds and Alephs and Volksamps and First Watts didn't count.
Grey
Grey
I dont think, thats what the fellow meant. After reading the post a couple of times, I think he expresses himself in a way thats a bit difficult to follow.
Steen🙂
I don't think it will be a tough field for Nelson to compete in at all. Last I saw, he pretty much owns the field!🙂
Hi
GRollins ---
So Nelson just began producing class A amps? Hmmm...I guess all those class A Thresholds and Alephs and Volksamps and First Watts didn't count.
Grey
------------------------------------------
so what, what is that supposed to mean?he can do whatever he
likes class-a has been around since the inventions of devices, mr
rollins is again amusing the forum with his oldtimer technology
i could comment on Pass's designs but that would mean i disclose
stuff even the so-called master doesnt know about but i wont do
it because as everyone knows our mr pass is a kind old man who
we find pleasure to talk to and his generocity and support of this
forum and diy community is larger than 100cm stereo tv
and mr rollins who always trys to explain to us pass's technologies has seen those little issues that make the masters
designs far from ideal class-as
we all know that this is not an attack at anyone in particular, mr rollins who has a wild imagination should know better than most
of us that i am not a product of his imagination
tell mr rollins why dont you ask mr pass who i really am, i am the
guy who sent him a technological invention for his opinion, have
you ever done that, i dont think you know what you talk about
most of the time you are an amusement park to me, have you ever identify issues with pass's designs if you have i urge you
to tell us about it, such an oltimer youare you should have spoted
them by now i think you will be stuck with that label the oldtimer
who got stuck and can not advance to bigger and better technologies
GRollins ---
So Nelson just began producing class A amps? Hmmm...I guess all those class A Thresholds and Alephs and Volksamps and First Watts didn't count.
Grey
------------------------------------------
so what, what is that supposed to mean?he can do whatever he
likes class-a has been around since the inventions of devices, mr
rollins is again amusing the forum with his oldtimer technology
i could comment on Pass's designs but that would mean i disclose
stuff even the so-called master doesnt know about but i wont do
it because as everyone knows our mr pass is a kind old man who
we find pleasure to talk to and his generocity and support of this
forum and diy community is larger than 100cm stereo tv
and mr rollins who always trys to explain to us pass's technologies has seen those little issues that make the masters
designs far from ideal class-as
we all know that this is not an attack at anyone in particular, mr rollins who has a wild imagination should know better than most
of us that i am not a product of his imagination
tell mr rollins why dont you ask mr pass who i really am, i am the
guy who sent him a technological invention for his opinion, have
you ever done that, i dont think you know what you talk about
most of the time you are an amusement park to me, have you ever identify issues with pass's designs if you have i urge you
to tell us about it, such an oltimer youare you should have spoted
them by now i think you will be stuck with that label the oldtimer
who got stuck and can not advance to bigger and better technologies
I remember those old Sony JFet amps 30 years ago, their flaw was losing gate bias causing an expensive accident. They did sound nice.
steenoes picture has a 96 date code so it cannot be a lovoltech part
The Lovoltech D-pak and SOT-89 parts can carry plenty of current, D-Pak in cascode would dissipate enough power to get 15W out
steenoes picture has a 96 date code so it cannot be a lovoltech part
The Lovoltech D-pak and SOT-89 parts can carry plenty of current, D-Pak in cascode would dissipate enough power to get 15W out
kilometer meter decimeter centimetermoe29 said:
km, m, dm, cm
it is units to define lenght, used in some countries
100cm TV, might be a television device with a screen 1 meter wide
I think this is what mastertech means to compare with
🙂
mr pass is a kind old man
who we find pleasure to talk to
and his generocity and support of this forum and diy community
is larger than 100cm stereo tv
Do these lovoltech jfets follow the usual zero temperature coefficient at Vp + 0.65 rule for njfets? Borbely used to bias his preamps for the zero temp co point, so there was no need to chase constant power.
Looking at the data sheets Vp is about zero for thes devices and they appear to be operated +ve Vgs ~ 0.6V
Looking at the data sheets Vp is about zero for thes devices and they appear to be operated +ve Vgs ~ 0.6V
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