A piece of trace which connects a base of MJE15035 TP6 with emitter of BC560.
White + shows the limits of the layout.
I made it little different.
Last edited:
Trust me, Loek is way better at layout design than you.
(me had several classes, including pcb layout, at the tech-U electronics building where Loekie works)
2d hint, white + in the cap C13 on the opposite side of C14
(me had several classes, including pcb layout, at the tech-U electronics building where Loekie works)
2d hint, white + in the cap C13 on the opposite side of C14
Last edited:
AndriyOL
Just to clarify things.
The layout is single sided.
The blue traces are wire connections.
And a freindly tone is what I prefer.
Just to clarify things.
The layout is single sided.
The blue traces are wire connections.
And a freindly tone is what I prefer.
wires
The blue wires are not touching the pcb, they are in the air. So no short at the cap.
If you follow the schematic you will find out.
You don't need to make the wires from the outside groundplanes if you are sure that the heatsink is grounded at the pcb at 4 points. Transistors has to be isolated!
It is not my design, Mihai gave the eagle files in the thread, in eagle i took all layers visible and then you can see the component location. Then made the pdf.
The gif file i found else.
I didnot make the amp and the psu .....
Regards, Loek
The blue wires are not touching the pcb, they are in the air. So no short at the cap.
If you follow the schematic you will find out.
You don't need to make the wires from the outside groundplanes if you are sure that the heatsink is grounded at the pcb at 4 points. Transistors has to be isolated!
It is not my design, Mihai gave the eagle files in the thread, in eagle i took all layers visible and then you can see the component location. Then made the pdf.
The gif file i found else.
I didnot make the amp and the psu .....
Regards, Loek
Loek,
in that case, Mihai is way better at it than you.
www.diyaudio.com/forums/solid-state...-stage-audio-power-amplifier.html#post1349254
Phew, 4 years ago already. 🙁
in that case, Mihai is way better at it than you.
www.diyaudio.com/forums/solid-state...-stage-audio-power-amplifier.html#post1349254
Phew, 4 years ago already. 🙁
Indeed Jacco. I used Protel years ago, nowadays its Altium. Not so easy to learn if you use it now and then...
But i have experienced students around me
But i have experienced students around me
Understood! Thanks. I have oversized components, so I have to little change the layout.
Hi again
Would it be an idea to use PMBFJ620 dual J-FET instead of 2x2sk170 as input?
http://www.datasheetcatalog.org/datasheet/philips/PMBFJ620_1.pdf
Only problem as I see it is the forward transfer
admittance wich is 10 mS as min. where 2sk170 has typ. 22 mS.
It dosent have the very low noise figure, but that should not be a problem in a power amp input?
Would it be an idea to use PMBFJ620 dual J-FET instead of 2x2sk170 as input?
http://www.datasheetcatalog.org/datasheet/philips/PMBFJ620_1.pdf
Only problem as I see it is the forward transfer
admittance wich is 10 mS as min. where 2sk170 has typ. 22 mS.
It dosent have the very low noise figure, but that should not be a problem in a power amp input?
Jacco, interesting comments on the ExtremeA.
I think this amp should get more attention.
Too bad there seem to be some "support" issues (not that anyone is obliged to give such support, but still...).
I think this amp should get more attention.
Too bad there seem to be some "support" issues (not that anyone is obliged to give such support, but still...).
completely different animal.
It might work. Can you simulate with it in lieu of the 170?
There is no information on level of matching !
It might work. Can you simulate with it in lieu of the 170?
There is no information on level of matching !
Hi
Could you advise me how to change the thermal compensation circuit of this amplifier to use Toshiba BJTs instead of thermaltrack devices?
Any help will be very appreciated.
Could you advise me how to change the thermal compensation circuit of this amplifier to use Toshiba BJTs instead of thermaltrack devices?
Any help will be very appreciated.
Look up the symasym schematic. Replace the FC-100 diode string and pot with the symasym's BD135 (or similar) and the resistive divider to its base.
SymAsym5 - Project
Hmm.
Maybe too low Gm, but that wouldn´t that just mean, that the openloop gain would be a little less, and therefor maybe the distortion figures a very small amount higher, as the feedback amount is reduced?
The cool thing about the device is that the two FETs track each other temperaturewise.
But again the drawbacks may be too servere.
Another candidate (I have in house!) could be 2sk363. Gm: typ 60 mS @ 15mA and IDss 5-30mA.
My problem is , that from the many 2sk170 I have here only very few has IDss > 9mA so I cannot match them good enough. Almost all of the 2sk363 has IDss > 9mA and the Phily dosen´t need to be matched, so they could be selected by highest Gm.
Hmmmm....
Maybe too low Gm, but that wouldn´t that just mean, that the openloop gain would be a little less, and therefor maybe the distortion figures a very small amount higher, as the feedback amount is reduced?
The cool thing about the device is that the two FETs track each other temperaturewise.
But again the drawbacks may be too servere.
Another candidate (I have in house!) could be 2sk363. Gm: typ 60 mS @ 15mA and IDss 5-30mA.
My problem is , that from the many 2sk170 I have here only very few has IDss > 9mA so I cannot match them good enough. Almost all of the 2sk363 has IDss > 9mA and the Phily dosen´t need to be matched, so they could be selected by highest Gm.
Hmmmm....
This design seems great!
Didn't yet read all the topic...
Is there a place where some measurements have been done?
Didn't yet read all the topic...
Is there a place where some measurements have been done?
Stack the PMBFJ´s to get higher GM ?
Maybe that could be a solution, and you would get better noise figure too, wouldn´t you?
Maybe that could be a solution, and you would get better noise figure too, wouldn´t you?