DC Servo MOSFET Amplifier

[rizqi]

ok sir,... thanks allot....
regard...

 

[rissotto]

Not every one, beginners in DIY have better look on his design becouse of size and colours, my design confuse beginners, and there is much more beginners than experts, and there is some people who want just clone expensive brand to get better price for sale clone, and don't want learn anything.
Regards

yeah thats true Apex!!!

 

[rizqi]

some redsign from my self

So that the best from beginer to make expert....... & i've build some design from mr. mile like B500 standart, B500 TEF and H900- all is hand made, but some pict can't upload here bcause bad camera....

regards😉🙂

 

[132222]

Old F100 schematic and pcb will be redesign.

hello Apex
I am from Iran
Circuit I've made ​​you a quote.(post 122) But does not work.
PSU, but have not built the circuit.
All components installed correctly. The schematic with transistor bf420 and bf421 board printed on it is different.
In case the printed installation pieces on the board. Voice was a little boost. But with very high noise and high loudspeaker diaphragm and coil it will be hot and very hot IRFP9240 MOSFET. The power output is 17 volts.
But when the transistor base, I just installed the schematic loudspeaker diaphragm remains high and the output voltage is 45 volts
Znrhay diode circuit within a few volts and watts are they?
ZY2V7:?
ZY15:?
ZF12:?

 

[apexaudio]

hello Apex
I am from Iran
Circuit I've made ​​you a quote.(post 122) But does not work.
PSU, but have not built the circuit.
All components installed correctly. The schematic with transistor bf420 and bf421 board printed on it is different.
In case the printed installation pieces on the board. Voice was a little boost. But with very high noise and high loudspeaker diaphragm and coil it will be hot and very hot IRFP9240 MOSFET. The power output is 17 volts.
But when the transistor base, I just installed the schematic loudspeaker diaphragm remains high and the output voltage is 45 volts
Znrhay diode circuit within a few volts and watts are they?
ZY2V7:?
ZY15:?
ZF12:?

CONNECT INPUT GND TO PSU GND...

 

[132222]

CONNECT INPUT GND TO PSU GND...

PSU should I create?

 

[Zinyx]

You must connect GND from transformer to input GDN signal. Understand?

 

[132222]

You must connect GND from transformer to input GDN signal. Understand?

Dear friend, I realized. You mean is that instead of the PSU, gnd gnd input circuit connected to you?
How do I transistors and the base install according to the schematic or the photo on the PCB?

 

[apexaudio]

This gnd wireing circuit from NX amp can be use for this amp.

 

[132222]

This gnd wireing circuit from NX amp can be use for this amp.

Thank you very much.
How do I transistors installed? Like schematic or PCB?

 

[132222]

Apex Where are you?

 

[rizqi]

x'Mile

martha in here,....

 

[apexaudio]

Thank you very much.
How do I transistors installed? Like schematic or PCB?

This can help

 

[132222]

This can help

I've installed this way. But does not work.

 

[132222]

HELP ME
PLZ........

 

[apexaudio]

HELP ME
PLZ........

Post better pictures both sides of pcb with psu and wireing. There is no yellow LED on your pcb, it's part of bias circuit not signal led...

 

[132222]

Thanks, all. Especially apex.
The problem was the LED and transistor.
Thank you very much.
I do not know how to thank.
Kiss for all

yahoo ID : masoud.lizard@att.net

ECA.ir
Signature:
DR.lizard from IRAN
Bye

 

[apexaudio]

Thanks, all. Especially apex.
The problem was the LED and transistor.
Thank you very much.
I do not know how to thank.
Kiss for all

yahoo ID : masoud.lizard@att.net

ECA.ir
Signature:
DR.lizard from IRAN
Bye

Good news,
Regards

 

[carlmart]

This old pcb with 5 pairs of outputs and protect can be redesign for FB400

I'm sorry if this was already mentioned or commented, but why use C6/47uF on feedback if there is a DC servo on that amp?

 

[apexaudio]

I'm sorry if this was already mentioned or commented, but why use C6/47uF on feedback if there is a DC servo on that amp?

I use TL071 instead pot for auto adjust DC offset, with C6 offset is +/-0.1mV and without C6 it's +/-1mV.