metal, the output transistors can easily be mounted off board as you say, just holes for the wires, and possibly make room for putting in a small transistor with a resistor on the board for yer very own darlingtons.
i like the sound of that, compact..![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
conserning the pcb you have allready posted, it's nice, i like the symetri, but for diyers making dublesided is perhaps a but to hard?
dunna, only make singlesided pcb's at school, and never god any solder to stick to em either.
just my 2 cents.
-Marius
i like the sound of that, compact..
conserning the pcb you have allready posted, it's nice, i like the symetri, but for diyers making dublesided is perhaps a but to hard?
dunna, only make singlesided pcb's at school, and never god any solder to stick to em either.
just my 2 cents.
-Marius
Hello demogorgon
When I first started drawing the PCB, I only put all passive components and LM4702 in the schematic.....I was able to make it singlesided for LM4702....cheer up guys![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
As I have already said, I will make it this way, one singlesided PCB for LM4702 which is the main PCB module here, and many optional singlesided PCBs for power output transistors stage. My self, I prefer to be able to put the transistors on a separate PCB, thats much more flexible, and helps the guys who can't obtain a specific transistor.
Any way, it seems we got three choices here:
1. Using MJ11031/2 darlingtons pairs, I will design one for them, to make the whole thingy looks neaty and nice, also the small diode transistor will be included in the power transistors PCB, any way, don't expect the PCB for TO-3 footprint to be small. This choice will be the most powerful, but not the best performing one in the high ends of the audio spectrum.
2. Using 2SB1594/2SD2449 darlingtons pairs, I still don't know if they are available, but this one will have the best perfomance in the whole range of audio spectrum, and the small diode transistor is also included in the power transistors PCB
3. Using MJL4281/4302 pairs, these are not darlingtons, and a PCB for them is a must, so we have to use MJE15035/4 pairs as drivers too, and the small diode transistor is also included in the power transistors PCB. This one will be very nice, in case we can find out how to calculate this resistor between the emmiters of 2SB1594 and MJE15035, the same applies to 2SD2449 and MJE15034.
Note that I have maintained the pure complementary structure for the last option of power transistors trying to obtain a nice design, and finally semi solid, semi chip audio power amplifier GC solution.
Let me know if there are any other suggestions![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
Please note that I will not post the new PCB designs till I receive the required components...
When I first started drawing the PCB, I only put all passive components and LM4702 in the schematic.....I was able to make it singlesided for LM4702....cheer up guys
As I have already said, I will make it this way, one singlesided PCB for LM4702 which is the main PCB module here, and many optional singlesided PCBs for power output transistors stage. My self, I prefer to be able to put the transistors on a separate PCB, thats much more flexible, and helps the guys who can't obtain a specific transistor.
Any way, it seems we got three choices here:
1. Using MJ11031/2 darlingtons pairs, I will design one for them, to make the whole thingy looks neaty and nice, also the small diode transistor will be included in the power transistors PCB, any way, don't expect the PCB for TO-3 footprint to be small. This choice will be the most powerful, but not the best performing one in the high ends of the audio spectrum.
2. Using 2SB1594/2SD2449 darlingtons pairs, I still don't know if they are available, but this one will have the best perfomance in the whole range of audio spectrum, and the small diode transistor is also included in the power transistors PCB
3. Using MJL4281/4302 pairs, these are not darlingtons, and a PCB for them is a must, so we have to use MJE15035/4 pairs as drivers too, and the small diode transistor is also included in the power transistors PCB. This one will be very nice, in case we can find out how to calculate this resistor between the emmiters of 2SB1594 and MJE15035, the same applies to 2SD2449 and MJE15034.
Note that I have maintained the pure complementary structure for the last option of power transistors trying to obtain a nice design, and finally semi solid, semi chip audio power amplifier GC solution.
Let me know if there are any other suggestions
Please note that I will not post the new PCB designs till I receive the required components...
Hey guys,
Just a note, I ordered some samples of these a while back and have a PCB complete for the 4702 and SAP16N and SAP16P which are temp compensated and thus eleminate two transistors from the circuit. Those devices are also very easy to parallel, although they do need a 200ohm pot/rheostat between the pairs to set the current.
Just waiting for the SAPs to get here.
Cheers!
Russ
Just a note, I ordered some samples of these a while back and have a PCB complete for the 4702 and SAP16N and SAP16P which are temp compensated and thus eleminate two transistors from the circuit. Those devices are also very easy to parallel, although they do need a 200ohm pot/rheostat between the pairs to set the current.
Just waiting for the SAPs to get here.
Cheers!
Russ
metal said:Oh yea Russ
Here we go![]()
Errrrmmmm?? What do you mean by that?
Sure. I always do.
When, before, or after selling the PCBs...
I will be interested to have these transistors as well...but not interested in buying PCBs from any one...
Well I guess you don't want it then. Seriously, I have given away nearly all of my PCB layouts, not sure where your angst comes from. Sorry if I stepped on your toes. Forget it if you like.
Well, I have asked you for the Sch & PCB files in eagle format many days ago for the design of the preamp/selector, till now, I have not seen any thingy from you....I thought you will never post any thing....
Any way, I am not angry, but I had the some doubts about you posting Sch & PCB files on the forum, which are clean now, we will be waiting for your work Russ
I will also post my work on the PCB, so we can improve the final PCB for this design, thats what I really want...
metal said:
which are clean now
Hmm what is clean?
The other (IO selector) design you requested of me is not my work alone, and I would not presume to give it away. You should not think any worse of me for that. That is very petty.
You should do some research. PDF and brd files of my designs are available on the forum.
Your attitude is only going to make people less prone to share. I suggest you treat contributers with a little more consideration.
Cheers!
Russ
russ,
Why making things more difficult here, while its much more simple. I asked you for the final eagle files, not for the PDFs nor the Brd file alone, your answer was not what you have already written here....but a little explaination at that time, just like the one you have already written, would have removed the vague many days ago...
Any way, I am always used to "consideration" for the members on the forum. What already happened here, shows that you are used to deal with sharing matters that way
anyway, a member who is used to share, won't just be proned because of me, I don't think so russ....I always receive private emails from many members thanking me for the sharings I did...any way, thanks for the sharing and contribution you did, and might do..
Why making things more difficult here, while its much more simple. I asked you for the final eagle files, not for the PDFs nor the Brd file alone, your answer was not what you have already written here....but a little explaination at that time, just like the one you have already written, would have removed the vague many days ago...
Any way, I am always used to "consideration" for the members on the forum. What already happened here, shows that you are used to deal with sharing matters that way
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