And finaly an amp that works : http://www.audio-electronics.go.ro/nmos100.html 😀 (it's Nmos200, but i name them on 8 ohms 
)
This Nmos works well, even from the first time. 😕
I don't have any problems. Sounds great !
I used IRFP460 and +/-50V DC rails.
)This Nmos works well, even from the first time. 😕
I don't have any problems. Sounds great !
I used IRFP460 and +/-50V DC rails.
where is the credit to the designer? or a link to DIYaudio thread?marus said:And finaly an amp that works : http://www.audio-electronics.go.ro/nmos100.html 😀 (it's Nmos200, but i name them on 8 ohms
This Nmos works well, even from the first time. 😕
I don't have any problems. Sounds great !
I used IRFP460 and +/-50V DC rails.
Hi Sek,
go to his link.
There is no mention that the design is based on Quasi's work.
But equally, he does not give away Quasi's schematic.
Nor link to Quasi's site.
go to his link.
There is no mention that the design is based on Quasi's work.
But equally, he does not give away Quasi's schematic.
Nor link to Quasi's site.
marus said:And finaly an amp that works : http://www.audio-electronics.go.ro/nmos100.html 😀 (it's Nmos200, but i name them on 8 ohms
This Nmos works well, even from the first time. 😕
I don't have any problems. Sounds great !
I used IRFP460 and +/-50V DC rails.
Marus,
Excellent work on the PCB. Do you think the IRFP460s will be ok with the heatsink you chose to use? Definitely a creative use of CPU heatsinks? I am curious about the smaller "L" heatsink temperature. Warm or hot to touch?
Did you get your NMOS350s working yet? You were going to redo the L1 coil last time you posted about your NMOS350s problems.
Regards,
John L. Males
Willowdale, Ontario
Canada
26 September 2007 11:57/12:17
26 September 2007 12:19 Typo correction. jlm
Official Quasi Thread Researcher
Andrew,
I see your point, but he didn't do that with his other site either, and nobody seemed to care. That's why I wasn't assuming you've been referring to his website, sorry.
But here goes also from my side...
Marus,
please give credit where credit is due. You might not feel that this is relevant for your personal projects, but you're on the internet. People can see your site, and they will mistakenly assume those designs being your work. Especially as you present everything as the very best, even the one that you didn't get to work properly yet. 😎
Cheers,
Sebastian.
I see your point, but he didn't do that with his other site either, and nobody seemed to care. That's why I wasn't assuming you've been referring to his website, sorry.
But here goes also from my side...
Marus,
please give credit where credit is due. You might not feel that this is relevant for your personal projects, but you're on the internet. People can see your site, and they will mistakenly assume those designs being your work. Especially as you present everything as the very best, even the one that you didn't get to work properly yet. 😎
Cheers,
Sebastian.
Andrew,
🙂 ... I just uploaded the pictures there so it won't be needed to upload them on tinypic.com or put them here and make a mess.
I can't call "that" a site ....
Keypunch,
The heatsink i used is just for tests 😀 ... I don't have other one.
But it surprised me today... it stays warm... at about 70W output power (of course, with a fan). To bad that i don't have two heatsinks like this....
The "L" one stays warm too.
I will make more precise measurements these days. I can't remember exactly today ones ... i was very excited 😀 😀 😀
Thank you Quasi ! This amp is my favorite !
Nmos350 is in the same state: not working .... but he will !
(i will put more pictures on "my site" )
🙂 ... I just uploaded the pictures there so it won't be needed to upload them on tinypic.com or put them here and make a mess.
I can't call "that" a site ....
Keypunch,
The heatsink i used is just for tests 😀 ... I don't have other one.
But it surprised me today... it stays warm... at about 70W output power (of course, with a fan). To bad that i don't have two heatsinks like this....
The "L" one stays warm too.
I will make more precise measurements these days. I can't remember exactly today ones ... i was very excited 😀 😀 😀
Thank you Quasi ! This amp is my favorite !
Nmos350 is in the same state: not working .... but he will !
(i will put more pictures on "my site"
)
Marus,
I could not see a fan in your NMOS100 pics, but of course a CPU heatsink has or it is very easy to source a fan for such a common heatsink. Just bear in mind even with the fan on the heatsink that the fan by nature causes dust to build up on the heatsink in a short time. The dust will quickly reduce the effectiveness of the fan as well as the heatsink. One reason I really do not like active cooling as it adds extra, but important, maintenance to the amplifier. I know you will find a larger heatsink.
I was more curious about the temperature of the "L" heatsink. It seems from your comments of it being "warm" that that is great as opposed to hot or cannot keep fingers on the heatsink too long.
Just an FYI I would not let more than about 180W be handled by the pair of IRFP460's you are using at about a Tc of 60C. I am not sure what your 70W reference impedance was measured to. But the 180W @ Tc 60C would be the the most in terms of music P-P I would have your NMOS100 drive at 8 ohms imdedance. I think you would be ok at 4 ohms imdedance to about 90W @ Tc of 60C.
With regads to your pics not being a "site", given you posted some text related to the specifications of the amplifiers I think you would not take much effort to place a link to this thread or quasi's web project page that your wonderfully made amplifiers are a result of quasi and the contributors to this thread. I do not think that is asking much nor woud it take much effort.
Regards,
John L. Males
Willowdale, Ontario
Canada
27 September 2007 (21:10 -) 21:28/21:46
Official Quasi Thread Researcher
I could not see a fan in your NMOS100 pics, but of course a CPU heatsink has or it is very easy to source a fan for such a common heatsink. Just bear in mind even with the fan on the heatsink that the fan by nature causes dust to build up on the heatsink in a short time. The dust will quickly reduce the effectiveness of the fan as well as the heatsink. One reason I really do not like active cooling as it adds extra, but important, maintenance to the amplifier. I know you will find a larger heatsink.
I was more curious about the temperature of the "L" heatsink. It seems from your comments of it being "warm" that that is great as opposed to hot or cannot keep fingers on the heatsink too long.
Just an FYI I would not let more than about 180W be handled by the pair of IRFP460's you are using at about a Tc of 60C. I am not sure what your 70W reference impedance was measured to. But the 180W @ Tc 60C would be the the most in terms of music P-P I would have your NMOS100 drive at 8 ohms imdedance. I think you would be ok at 4 ohms imdedance to about 90W @ Tc of 60C.
With regads to your pics not being a "site", given you posted some text related to the specifications of the amplifiers I think you would not take much effort to place a link to this thread or quasi's web project page that your wonderfully made amplifiers are a result of quasi and the contributors to this thread. I do not think that is asking much nor woud it take much effort.
Regards,
John L. Males
Willowdale, Ontario
Canada
27 September 2007 (21:10 -) 21:28/21:46
Official Quasi Thread Researcher
Hi guys,
In the TO220 version of the NMos200, where should the T8 be mounted? Does it have to be between the L bracket for the IRFs and the PCB?
Thanks,
Vivek
In the TO220 version of the NMos200, where should the T8 be mounted? Does it have to be between the L bracket for the IRFs and the PCB?
Thanks,
Vivek
Vivek,
I am not quite sure what you are asking. That said, for the physical configuration of the NMOS100 (TO-220 version) PCB T8 will need to be placed in middle between the output driver MOSFETs. Some builders will mount a Vbe T8 like device ontop of one of the output drivers, but there is divided opinion in the DIY community doing so is appropriate. The NMOS100 T8 can either be mounted in a hole into the output heatsink or to the surface. Some builders have chosen to use a TO-126 type device for T8 on the NMOS350/500. You can use a TO-126 device for T8 if you wish, but I am not sure if any builders of the NMOS100 have done do.
Regards,
John L. Males
Willowdale, Ontario
Canada
30 September 2007 11:22
Official Quasi Thread Researcher
I am not quite sure what you are asking. That said, for the physical configuration of the NMOS100 (TO-220 version) PCB T8 will need to be placed in middle between the output driver MOSFETs. Some builders will mount a Vbe T8 like device ontop of one of the output drivers, but there is divided opinion in the DIY community doing so is appropriate. The NMOS100 T8 can either be mounted in a hole into the output heatsink or to the surface. Some builders have chosen to use a TO-126 type device for T8 on the NMOS350/500. You can use a TO-126 device for T8 if you wish, but I am not sure if any builders of the NMOS100 have done do.
Regards,
John L. Males
Willowdale, Ontario
Canada
30 September 2007 11:22
Official Quasi Thread Researcher
John, that is what I wanted to know. I thought T8 had to be sandwiched between the heatsink and the PCB. Thanks for that.
Vivek said:
Vivek said:
Vivek,
I found the link to Marus' NMOS100 still works. I noticed from Marus' NMOS100 pics why you may have suggested T8 needing to be sandwiched between heatsink and PCB. It appears Marus used a TO-126 (sandwiched between PCB and heatsink) for his NMOS100 and not a TO-92 per the attached image from Marus' web page.
Regards,
John L. Males
Willowdale, Ontario
Canada
01 October 2007 09:05
01 October 2007 23:59
02 October 2007 00:02 Added clarifying text. jlm
Official Quasi Thread Researcher
Yeah, I used MJE340 ... one like those used for T7 and T9 ... and it seems to work fine. (I'm not quite sure... today i think i'll test it at full load "100W" sinusoidal power 
to see what will happend).
I change the PCB a little to match the TO-126.
I want to be someting verry clear :
1. All powers that I'm referring to, in my posts, it's RMS power on 8 ohms. (unless specified)
2. All voltage rails I'm referring to, in my posts, it's DC voltage rails. (unless specified)
to see what will happend).I change the PCB a little to match the TO-126.
I want to be someting verry clear :
1. All powers that I'm referring to, in my posts, it's RMS power on 8 ohms. (unless specified)
2. All voltage rails I'm referring to, in my posts, it's DC voltage rails. (unless specified)
Vivek said:
You can for the second stage but not for the third, because with rails of 50v the Vce will be exceeded.
Cheers
Q
Hi Quasi,
The datasheet of BD139 says Vceo is 80V. I do not understand. Could you please explain this to me?
I could not find MJE340/350 in the local market. Are there any other tansistors you can suggest?
Thanks,
Vivek
The datasheet of BD139 says Vceo is 80V. I do not understand. Could you please explain this to me?
I could not find MJE340/350 in the local market. Are there any other tansistors you can suggest?
Thanks,
Vivek
