Juan is busy, he is making his new Dx Supply pcboard
reason why he is not following the thread right now.
I love french culture (la langue et civilization française)....my home town, Rio de Janeiro, has french culture because we had french invaders a few hundred years ago....house there is Maison...table to serve food is buffet.... driver is Chauffeur.... Filet Mignon is steak.
Invaders? they mixed with the population and nobody knew more who' who.
Rio de Janeiro girls are so nice because the mix of french (blonde), African (nice body shape) and Portuguese (the golden skin)
Hehehehehe...nice to read "dissipateur" in french...easy to me as portuguese..thanks lord.
Very few french citizen have assembled my amplifiers...i do imagine because BJT... i see that in France they love FETs as i use to type my search in french to see things from France.
regards,
Carlos
reason why he is not following the thread right now.
I love french culture (la langue et civilization française)....my home town, Rio de Janeiro, has french culture because we had french invaders a few hundred years ago....house there is Maison...table to serve food is buffet.... driver is Chauffeur.... Filet Mignon is steak.
Invaders? they mixed with the population and nobody knew more who' who.
Rio de Janeiro girls are so nice because the mix of french (blonde), African (nice body shape) and Portuguese (the golden skin)
Hehehehehe...nice to read "dissipateur" in french...easy to me as portuguese..thanks lord.
Very few french citizen have assembled my amplifiers...i do imagine because BJT... i see that in France they love FETs as i use to type my search in french to see things from France.
regards,
Carlos
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The heat sink I use those not have the leads that bond the heat sink to the board here are the one similar to it, but and my next order those changes are made now is better because project16 help use with his information thank you project16. there are no so nice like the golden ones but will work. 
Regards
Juan
Regards
Juan
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Thank you Juan.
The same heatsink but shorter.
HS-123-25 STONECOLD - Dissipateur: pressé | Transfer Multisort Elektronik
Regards!
The same heatsink but shorter.
HS-123-25 STONECOLD - Dissipateur: pressé | Transfer Multisort Elektronik
Regards!
My dear friend Newton have soldered some transistors inverted
and this happened one or two months ago.... he travelled to USA and now he is back home adjusting the Dx Super A
Watch the video:
Teste do DX Super A regulagem da corrente - YouTube
regards,
Carlos
and this happened one or two months ago.... he travelled to USA and now he is back home adjusting the Dx Super A
Watch the video:
Teste do DX Super A regulagem da corrente - YouTube
regards,
Carlos
Nabuco Speaker Protector - Update
Hello Carlos!
Thank's Greg Erskine
For the protection of speakers in my DX Super A, I reported the latest small changes and adapted the PCB.
73's!
Hello Carlos!
Thank's Greg Erskine
For the protection of speakers in my DX Super A, I reported the latest small changes and adapted the PCB.
73's!
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Very good Metal
This pcboard is our pride.... Juan and me (more Juan than me) worked hard on that, more than 45 days going and returning videos discussing details about it.
I do think this one is the most beautifull pcboard ever made to the Dx amplifier...we had attention to details, even magnetic coupling, lenght of copper tracks, capacitances in between tracks, heatsinks behaving alike shield for magnetic radiation .
VAS heatsink can be grounded below the pcboard to behave alike a wall to impeach magnetic field to reach the first VAS transistor, also the second VAS goes insulated from the heatsink that may be grounded.
Tracks width and length was discussed in details, parts positioning to avoid coupling, parts arranged in symmetric way to look good, to look organized, we have discussed vertical alignment and horizontal alignment of parts, equal clearances in between parts, components not touching one each other, clearance, room or distance in between input and output and several other details.
We fail because it is not painted both sides...this was a decision failure taken by Juan.... not me..... i have to say i am not guilty because of that.
Juan was so moved by the Chinese girl made contact with him to prepare the pcboard files to manufacture that he forgot to paint both sides..ahahahahahah!
This is the one made me entirelly satisfied... we discussed about each link, each track...also the idea that links are better than long run of copper tracks was applied...even computer have these links but you do not see them because they cross one side to the other in the mother board.... this reduces length or copper tracks that results in lower inductance.
Was art work... thanks to Juan efforts and thanks that i decided to be very demanding and to make direct interference saying change this and that.
This was possible, also, because of Juan's personality...he is latine like me, and this makes our relationship easier..he is humble and do not discuss my decisions and use these moments to understand and to learn more about such kind of details and problems related one decision compared to the other.. was possible also because i decide to do the job together Juan, as you know i hate to make pcboard layout, reason why i ask people to make them to me, and i do let people doing not to bother myself with this stuff...this is not that good because i am skilled related technical problems found in the pcboard..so, i have to do it together...i usually deny to cooperate..but this time i have decided to make together....30 percent of this extraordinary work was because of me....70 percent because of Juan Vargas.
regards,
Carlos
This pcboard is our pride.... Juan and me (more Juan than me) worked hard on that, more than 45 days going and returning videos discussing details about it.
I do think this one is the most beautifull pcboard ever made to the Dx amplifier...we had attention to details, even magnetic coupling, lenght of copper tracks, capacitances in between tracks, heatsinks behaving alike shield for magnetic radiation .
VAS heatsink can be grounded below the pcboard to behave alike a wall to impeach magnetic field to reach the first VAS transistor, also the second VAS goes insulated from the heatsink that may be grounded.
Tracks width and length was discussed in details, parts positioning to avoid coupling, parts arranged in symmetric way to look good, to look organized, we have discussed vertical alignment and horizontal alignment of parts, equal clearances in between parts, components not touching one each other, clearance, room or distance in between input and output and several other details.
We fail because it is not painted both sides...this was a decision failure taken by Juan.... not me..... i have to say i am not guilty because of that.
Juan was so moved by the Chinese girl made contact with him to prepare the pcboard files to manufacture that he forgot to paint both sides..ahahahahahah!
This is the one made me entirelly satisfied... we discussed about each link, each track...also the idea that links are better than long run of copper tracks was applied...even computer have these links but you do not see them because they cross one side to the other in the mother board.... this reduces length or copper tracks that results in lower inductance.
Was art work... thanks to Juan efforts and thanks that i decided to be very demanding and to make direct interference saying change this and that.
This was possible, also, because of Juan's personality...he is latine like me, and this makes our relationship easier..he is humble and do not discuss my decisions and use these moments to understand and to learn more about such kind of details and problems related one decision compared to the other.. was possible also because i decide to do the job together Juan, as you know i hate to make pcboard layout, reason why i ask people to make them to me, and i do let people doing not to bother myself with this stuff...this is not that good because i am skilled related technical problems found in the pcboard..so, i have to do it together...i usually deny to cooperate..but this time i have decided to make together....30 percent of this extraordinary work was because of me....70 percent because of Juan Vargas.
regards,
Carlos
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No good results using MJ transistors
Better to use BD139/140, they match perfectly.
The only problem you may face is that you cannot use voltage higher than 42 volts...you can use lower voltages, but never higher because they cannot hold the peak to peak voltage.
Many comparative tests made, and the conclusion is that not only sonically but also into the simulator, the BD139/140 produces much better result.
We have used into the Supercharged line of amplifiers..the blue boards have used MJ transistors and also 2N5401/2N5551.... we did that way to have a standard of transistors...we were forced to use MJ transistors despite we had did not wanted them...because of supply voltage to the Supercharged we had to use...but we felt the disadvantage in performance.
Reason why i have returned to 35 to 42 voltage range...mainly to use the BD139 and BD140 and also BC546 and BC556.
It gonna work metal...no problems about that...the sound...the performance is worse.
regards,
Carlos
Better to use BD139/140, they match perfectly.
The only problem you may face is that you cannot use voltage higher than 42 volts...you can use lower voltages, but never higher because they cannot hold the peak to peak voltage.
Many comparative tests made, and the conclusion is that not only sonically but also into the simulator, the BD139/140 produces much better result.
We have used into the Supercharged line of amplifiers..the blue boards have used MJ transistors and also 2N5401/2N5551.... we did that way to have a standard of transistors...we were forced to use MJ transistors despite we had did not wanted them...because of supply voltage to the Supercharged we had to use...but we felt the disadvantage in performance.
Reason why i have returned to 35 to 42 voltage range...mainly to use the BD139 and BD140 and also BC546 and BC556.
It gonna work metal...no problems about that...the sound...the performance is worse.
regards,
Carlos
The problem is not the MJ quality....it sounds very good
It is a very good transistor.... MJ is not bad..... it is good...but the BD139/140 is much better.
One is very good, and other is excellent...or one have not matched my amplifier, when BD139/140 matched perfectly.
Alike a hand inside a glove.... perfect!
regards,
Carlos
It is a very good transistor.... MJ is not bad..... it is good...but the BD139/140 is much better.
One is very good, and other is excellent...or one have not matched my amplifier, when BD139/140 matched perfectly.
Alike a hand inside a glove.... perfect!
regards,
Carlos
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Here you have pages about my amplifiers using MJ transistors
The multimodel pcboard offered by Mitchell a couple of years ago:
DX Blame Amplifiers - Carlos Mergulhão
regards,
Carlos
The multimodel pcboard offered by Mitchell a couple of years ago:
DX Blame Amplifiers - Carlos Mergulhão
regards,
Carlos
For better performance, use the Dx Supply or any series pass
regulator (with error amplifier) together this power amplifier.
Here you have the link to the Dx Supply thread and the post that shows the new updated layout for home etching.
Untested the layout...circuit hardly tested and approved.... this means the layout can have error...we check many times..but better you to check prior to assemble... refer to the schematic.
Here you have the link:
http://www.diyaudio.com/forums/powe...put-adjustable-stabilized-power-supply-9.html
regards,
Carlos
regulator (with error amplifier) together this power amplifier.
Here you have the link to the Dx Supply thread and the post that shows the new updated layout for home etching.
Untested the layout...circuit hardly tested and approved.... this means the layout can have error...we check many times..but better you to check prior to assemble... refer to the schematic.
Here you have the link:
http://www.diyaudio.com/forums/powe...put-adjustable-stabilized-power-supply-9.html
regards,
Carlos
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