Simple Symetrical Amplifier

[Idefixes]

I have not done simulation with the BD 140/139 pair.. so I think you must experiment a little..

You can measure the current in the output stage over the fuse..With my driver set simulation suggests something like 250 ohms...(I would use the trimmer to find the right value an than change to a fixed resistor)

Also the resistors setting the Driver stage current can vary a little.. in my simulations (with different drivers) 140 ohm gives app 20 mA which will be just fine..
good luck.

Ok than i will mount 14ohm on socket (that will allow me to replace and tweak easily without desoldering). For R13 I will reduce a little the initial value (300R) and complet with trimmer to find the right value.

Marc

 

[Idefixes]

Miib,

Won't the actualy fuse place indicate the current in the "SSA" stage and the output stage?

Marc

 

[Idefixes]

Miib,

Won't the actualy fuse place indicate the current in the "SSA" stage and the output stage?

Marc

I self answer me after reading the topic. The mesure across fuse place (replaced by resistor) indicate outpu current by deducting input driver current (2-5mA not significant toward output current) and driver current.
Right?

Marc

 

[Idefixes]

There is a mistake on my schema and than on my PCB : Q8 ECF20P20 is in the wrong sens Source to V- and not to OUT. I will correct. Thanks Helan for pointing.

Marc

 

[radio]

Hi ALL!!
I am finishing this amplifier!!
Give the schematic and makes the final PCB for this amplifier with the transistors pair of outgoing 2SC5200/2SA1943, with power supply Ucc = + /-36VDC.
great thanks and cheers !

P.S.
Hi and cheers Alex !

 

[AndrewT]

Hi,
you have shown capacitors across the rectifying diodes.
You may find that this increases the HF noise that is fed into the PSU.

Allow space to add a resistor in series with each capacitor.
See Hagerman and snubbers, etc.

 

[Idefixes]

Hi ALL!!
I am finishing this amplifier!!
Give the schematic and makes the final PCB for this amplifier with the transistors pair of outgoing 2SC5200/2SA1943, with power supply Ucc = + /-36VDC.
great thanks and cheers !

P.S.
Hi and cheers Alex !

Are planing to share pcb and schematic to allows other to try?

Marc

 

[Lazy Cat]

SSA lucky DIY-er

Hi guys.

Nice to see some activity in SSA thread.

Who will be the next lucky DIY-er to experience the sound of SSA?

Regards to all, Andrej

 

[Idefixes]

Hi,
you have shown capacitors across the rectifying diodes.
You may find that this increases the HF noise that is fed into the PSU.

Allow space to add a resistor in series with each capacitor.
See Hagerman and snubbers, etc.

Thanks AndrewT, I was thinking so too as an improvement, and for first fire up i plane to not mount 100n caps...I have enough place this serie resistor. I will do this modification.

Marc

 

[radio]

Are planing to share pcb and schematic to allows other to try?

Marc

Hi
Good people (if I understood well) Why not??
thanks

Postscript
Only good and positive people can do such things!

 

[Lazy Cat]

HI.

The SSAstage and the listening-impresions given by members and constructor looks very promising!

I wonder if this outputstage can be used ?
My simulator says yes, but I`m not a simulatorwisard as some of you are.

I`m in the prosess of building a Amp with this output, ( bought and matched transistors)
but I`ll be happy if I can use SSA instead of the complicatet Electrocompaniet schematic.

Will you actually built it?

 

[Idefixes]

Hi
Good people (if I understood well) Why not??
thanks

I plane to try SSA with exicon lateral mosfet (that i ahve to purchase)on same rail voltage, but as i have a good stock of MJL3281/1302, the try on SSA could be faster. If you want/can only share your fonctionnel schematic it's good for me.

Marc

 

[radio]

I plane to try SSA with exicon lateral mosfet (that i ahve to purchase)on same rail voltage, but as i have a good stock of MJL3281/1302, the try on SSA could be faster. If you want/can only share your fonctionnel schematic it's good for me.

Marc

OK, Let shoot!
Give the display PCB layout with MJL3281/1302!!
Thanks

 

[Idefixes]

OK, Let shoot!
Give the display PCB layout with MJL3281/1302!!
Thanks

Sorry, i don't understand what you mean? MJL3281/1302 can directly replace 2SC5200/2SA1930.

Marc

 

[AndrewT]

Toshiba's 2sa1943/c5200 are their replacement for the often faked 2sa1302/c3281
ONsemi brought out their own equivalent and labeled it MJL. They have since brought out a family of similar devices (probably about 30 so).

 

[radio]

Sorry, i don't understand what you mean? MJL3281/1302 can directly replace 2SC5200/2SA1930.

Marc

Give PCB with MJL3281 /MJL1302,....Where do you see the difference practical with 2SC5200/2SA1943???
there is a problem!!??
thanks

 

[AndrewT]

It's past the time that you should have downloaded the respective datasheets and compared physical and electrical characteristics.

 

[radio]

It's past the time that you should have downloaded the respective datasheets and compared physical and electrical characteristics.

Friends
This is the same as the search for a hair in the egg!
Advertising, ... advertising, ... where are the people .. and where the introduction !!????
Regards !!

P.S.
shades !!??

 

[Smiley 09]

Have a Look . .

radio,

Please have a look here:
MJL3281 /MJL1302
and
2SC5200/2SA1943

Hope this help,

Cheers,

A.

 

[Josip_Del]

Will you actually built it?

Question is not referred to me but I will build it, just wont to know power of amp MJL3281/1302A 35VDC and have you any other suggestions like can voltage be 40VDC, and bias current?
thanks