Ok, I've made a few more changes to accomodate the good suggestions.
- I have inserted a resistor (82R or whatever final value it will be)
- I have moved D5 away from the FET so that it is less affected by heat from the FET. D5 can also be a zener or a link I imagine.
- for D5 I have added an extra solder PAD to potentially accomodate a LED.
- a couple of spare pads across D5 for something else....
This board will give me a few options as I play around.
Cheers Folks
Quasi
- I have inserted a resistor (82R or whatever final value it will be)
- I have moved D5 away from the FET so that it is less affected by heat from the FET. D5 can also be a zener or a link I imagine.
- for D5 I have added an extra solder PAD to potentially accomodate a LED.
- a couple of spare pads across D5 for something else....
This board will give me a few options as I play around.
Cheers Folks
Quasi
Attachments
Hi,
Actually, both kelvin and degree Celsius are alright...
But the SI recommendation is to use kelvin(s) with lower case spelling...
Other dictionaries state similarly.
That was fun to research, because I always wanted to get this sorted (and stop mixing em up myself). 😉
Cheers.
Actually, both kelvin and degree Celsius are alright...
But the SI recommendation is to use kelvin(s) with lower case spelling...
Other dictionaries state similarly.
That was fun to research, because I always wanted to get this sorted (and stop mixing em up myself). 😉
Cheers.
Hi Sek,
I think wiki is wrong.
Kelvin are K and describe an absolute temperature.
Centigrade = Celcius are degC and describe an absolute temperature.
k is the multiplier and should be upper case but to avoid confusion with kelvin was made lower case and the only multiplier that is lower case
All the dividers are lower case.
If you want to describe a difference in temperature then K will not do. C on it's own can be confusing. degC is a temperature so I and many others were taught to swap the order to Cdeg to indicate that temperature is not what is being used.
I think wiki is wrong.
Kelvin are K and describe an absolute temperature.
Centigrade = Celcius are degC and describe an absolute temperature.
k is the multiplier and should be upper case but to avoid confusion with kelvin was made lower case and the only multiplier that is lower case
All the dividers are lower case.
If you want to describe a difference in temperature then K will not do. C on it's own can be confusing. degC is a temperature so I and many others were taught to swap the order to Cdeg to indicate that temperature is not what is being used.
Hey Andrew,
I agree that wikipedia might be inaccurate, but I don't think they are plain wrong.
The notable news for me (not only from wikipedia) was that the standard usage of K, k and °C changed multiple times - and that even scientists regularly do it wrong.
One thing is for sure I'd say: the common misconception of °C being an absolute and K being a relative measure is in fact wrong since 1969. But it still persists in literarure and textbooks because it feels so convenient. 😉
My take is that everyone stands to what they adopted back in school and how their respective teachers had learned it.
Sebastian 😎
I agree that wikipedia might be inaccurate, but I don't think they are plain wrong.
The notable news for me (not only from wikipedia) was that the standard usage of K, k and °C changed multiple times - and that even scientists regularly do it wrong.
One thing is for sure I'd say: the common misconception of °C being an absolute and K being a relative measure is in fact wrong since 1969. But it still persists in literarure and textbooks because it feels so convenient. 😉
My take is that everyone stands to what they adopted back in school and how their respective teachers had learned it.
Sebastian 😎
If you are prepared to accept my changes then your observation is very true.sek said:
That's why I as a teacher abhor the British practice of teaching solely SI units in a metricated country, this being done in ignorance due to the predominance of Scientists on the pratical staff roll. In case some of you don't see the significance of that, the Scientists rightly use the CGS system where cm is the common length measurement, but when we went metric we adopted the MKS system where m rules. We should teach mm & m wh ich are the length units used throughout our industries.
How did you get °C where I have to use degC?
A little off topic now, but... 😀
I just saw this mentioned. This looks odd to me: C°
There is disagreement on wether it should be 'x° C' or 'x °C', but I'm afraid there is no such thing as 'x C°'... 😀
The confusion between 'stand to' and 'stand by' might be due to my lack of fluent English. 😉
Regarding the everyone-many difference, I was intentionally exaggerating. 😉
Your last change alters the meaning a little: I was referring to the fact that, when you get taught, you somehow depend on the character and will of your teacher. My experience is that many of them don't want to adopt some of the changes scientific advancement brings to them, thus they go on teaching what the are used to.
It's [Shift + ^] on any German keyboard. 😎
Your Mac 😀 allows you to enter it via [Option + Shift + 8] on English keyboards. I have no idea where it sits on keyboards in other countries, but the keyboard viewer helper application will tell you on any Mac.
On Windows systems it can be typed by [Alt + 0176] on the numeric keypad (simply hitting the four number keys one after another while holding down the Alt key).
Linux and some Unices allow it by typing [AltGr + Shift + 0].
There might be other ways to type it (depending on the software you have installed) and you can never be sure that it gets through correctly just because one can see it on the own screen...
Cheers,
Sebastian.
I just saw this mentioned. This looks odd to me: C°
There is disagreement on wether it should be 'x° C' or 'x °C', but I'm afraid there is no such thing as 'x C°'... 😀
The confusion between 'stand to' and 'stand by' might be due to my lack of fluent English. 😉
Regarding the everyone-many difference, I was intentionally exaggerating. 😉
Your last change alters the meaning a little: I was referring to the fact that, when you get taught, you somehow depend on the character and will of your teacher. My experience is that many of them don't want to adopt some of the changes scientific advancement brings to them, thus they go on teaching what the are used to.
It's [Shift + ^] on any German keyboard. 😎
Your Mac 😀 allows you to enter it via [Option + Shift + 8] on English keyboards. I have no idea where it sits on keyboards in other countries, but the keyboard viewer helper application will tell you on any Mac.
On Windows systems it can be typed by [Alt + 0176] on the numeric keypad (simply hitting the four number keys one after another while holding down the Alt key).
Linux and some Unices allow it by typing [AltGr + Shift + 0].
There might be other ways to type it (depending on the software you have installed) and you can never be sure that it gets through correctly just because one can see it on the own screen...
Cheers,
Sebastian.
ltspice simulation
I am planning to make a couple of actrk600 modules so have simulated it in Ltspice just to have a understanding of its working. I am posting the files here. Pls post your reviews whether the schematic is ok or not..as this is my first simulation project.
Thanks in advance.
I am planning to make a couple of actrk600 modules so have simulated it in Ltspice just to have a understanding of its working. I am posting the files here. Pls post your reviews whether the schematic is ok or not..as this is my first simulation project.
Thanks in advance.
Just had alook at your simulation QFX98,
You have doen some really good work !
sim seems to work fine when i run it
-Dan
You have doen some really good work !
sim seems to work fine when i run it
-Dan
danieljw said:
Thanks Danieljw for looking into the simulation. I have tried my best as per my knowledge to simulate it but still havn't figured out how to simulate the thermal coupling and check the thermal effects on the schematic. It would be very helpful if someone experienced in this can throw some light on it or its very possibility of it.
Thanks again in advance.
Biren.
Hi Quasi,
First of all I would like to thank and congatulate you for creating such a beautiful amp. (Havn't made it yet, but looking at everyone's response to it...it sure is.)
You seem to have made some changes in the schematic for the betterment.
So ultimately what are your findings (I am curious) and also would you suggest the changes to be included in your final schematic?
Thanks once again.
Biren.
First of all I would like to thank and congatulate you for creating such a beautiful amp. (Havn't made it yet, but looking at everyone's response to it...it sure is.)
quasi said:
You seem to have made some changes in the schematic for the betterment.
So ultimately what are your findings (I am curious) and also would you suggest the changes to be included in your final schematic?
Thanks once again.
Biren.
Hi Biren,
I will post an updated schematic plus an updated layout here and on the website shortly.
Cheers
Quasi
I will post an updated schematic plus an updated layout here and on the website shortly.
Cheers
Quasi
Hi Quasi,
I realy enjoy this schematic and I want to make the Aktrk600 but I want to use it as a stable and a good amplifier for PA.
Have you ever measured the THD of this amplifier ? Why I am asking this? Because I simulated it in NI Multisim and it have some problems whit frequences over 10KHz.
Greetings and Happy new year.
I realy enjoy this schematic and I want to make the Aktrk600 but I want to use it as a stable and a good amplifier for PA.
Have you ever measured the THD of this amplifier ? Why I am asking this? Because I simulated it in NI Multisim and it have some problems whit frequences over 10KHz.
Greetings and Happy new year.
Bogdantogo said:
Hi Bogdantogo,
I haven't built the Aktrk600 but Danieljw has. You should ask him what it's like.
http://www.diyaudio.com/forums/showthread.php?postid=1303252#post1303252
Cheers
Q
Construction Guide
I have added a construction and set up guide for this amp on my web site.
Cheers
Q
I have added a construction and set up guide for this amp on my web site.
Cheers
Q
Allthough a little bit of topic but then again it's not.
Have a look here:
http://www.diyaudio.com/forums/showthread.php?postid=1422436#post1422436
Let's get armed against counterfeit transistors who can create havoc with such a beatyfull amp as Quassie's.
Cheers,
Tarzan
Have a look here:
http://www.diyaudio.com/forums/showthread.php?postid=1422436#post1422436
Let's get armed against counterfeit transistors who can create havoc with such a beatyfull amp as Quassie's.
Cheers,
Tarzan
Hi,
After some playing in spice, i've come to conclude that this design delivers tremendous power even at 8R load compared to super leach. But, super leach has wide bandwidth and superior linearity. Actrk600 best suited for subwoofer amp while super leach for full range.
regards,
Roland
After some playing in spice, i've come to conclude that this design delivers tremendous power even at 8R load compared to super leach. But, super leach has wide bandwidth and superior linearity. Actrk600 best suited for subwoofer amp while super leach for full range.
regards,
Roland
Hi Rolandong
This amp is intended to be used as a high quality and high power PA amp or musical instrument amplifier. It does have good bandwidth extending to beyond 40Khz and for PA applications is more than adequate (maybe too much).
In any case the bandwidth can easily be improved by changing a few components but this is not recommended for this design.
I have not looked at the Leach at all so I can't comment there.
Cheers
Quasi
This amp is intended to be used as a high quality and high power PA amp or musical instrument amplifier. It does have good bandwidth extending to beyond 40Khz and for PA applications is more than adequate (maybe too much).
In any case the bandwidth can easily be improved by changing a few components but this is not recommended for this design.
I have not looked at the Leach at all so I can't comment there.
Cheers
Quasi
Quasi,
It occurs to me that a modification to the Aktrk topology amp's second stage CCS could provide nearly perfect thermal tracking. You could make it a 'ring of two' CCS, the trick being that the transistor being used as the current sense element should be a MOSFET instead of a BJT. Normally, in such a CCS the BJT senses current by having it's B-E junction across the emitter resistor of the main BJT. In this case, it would be the G-S of a HEXFET such as the IRF510/610/520 and the like (actually many types could be used). The HEXFET would of course be mounted onto the heatsink. Since it has a nice metal tab for heat transfer, it should have a lot less thermal inertia than a plastic TO92. The source and drain terminals should b bypassed by a small capacitor to insure the ring of two CCS stability and enable the HEXFET to be placed a fair distance away from the CCS should the layout require it. Vgs thermal characteristics will then track the output MOSFETs.
It occurs to me that a modification to the Aktrk topology amp's second stage CCS could provide nearly perfect thermal tracking. You could make it a 'ring of two' CCS, the trick being that the transistor being used as the current sense element should be a MOSFET instead of a BJT. Normally, in such a CCS the BJT senses current by having it's B-E junction across the emitter resistor of the main BJT. In this case, it would be the G-S of a HEXFET such as the IRF510/610/520 and the like (actually many types could be used). The HEXFET would of course be mounted onto the heatsink. Since it has a nice metal tab for heat transfer, it should have a lot less thermal inertia than a plastic TO92. The source and drain terminals should b bypassed by a small capacitor to insure the ring of two CCS stability and enable the HEXFET to be placed a fair distance away from the CCS should the layout require it. Vgs thermal characteristics will then track the output MOSFETs.
Hi Ilimzn,
As you can see I've been thinking about the theraml tracking for quite some time. I wonder if you could provide a rough sketch so that I could be clear about what you mean by "ring ccs". I read it as a double ended ccs so a drawing would remove any confusion.
Everything else you say of course makes sense.
Cheers and thanks for your input.
Q
As you can see I've been thinking about the theraml tracking for quite some time. I wonder if you could provide a rough sketch so that I could be clear about what you mean by "ring ccs". I read it as a double ended ccs so a drawing would remove any confusion.
Everything else you say of course makes sense.
Cheers and thanks for your input.
Q
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