A-class Preamp PSU

[apexaudio]

VR 1k must be replaced with 4k7 for BF245A, and regulation output voltage will be from +/12V to +/-24V.

 

[apexaudio]

PSU for preamps with Serial Regulator.

 

[apexaudio]

PCB for +/-15V PSU

 

[nikko]

Greetings to all.

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An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

This is an excellent,thanks Mr.Mile.

 

[apexaudio]

Nikko, is there any sound improvement with this shunt regulator?

 

[nikko]

What to say, this is so far the best PSU for me.I did not expect this, few parts and simple????
To be fair, a friend was doing the same thing, that now we are pleasantly surprised.
Thank you for this PSU)
Only repeat that all I apologize for my bad English

 

[apexaudio]

I replace PSU (7815/7915) in this phono MM preamp with this shunt regulator. I was surprise with unexpected extreme sound improvement.

 

[nikko]

I believe, only heal ourselves from the turntables, greeting)
Again when you think about it,hmmmmmmmm,maybe it's time forturntables))))))))))

 

[viktor1986]

Nice work Nikko!

3 x 1N4148 can be replased with the red led diode(Vf = 1.8V).

What is the voltage at the output when you turn on power supply and how much is after 10 minutes?

 

[apexaudio]

I suggest to use multyturn pot for VR 4k7, in that case voltage can be set to 15,00V and it's dificult with standard pot.

 

[44250]

Regulated PSU for power amplifiers. Output voltage can be set and stabilised from +/-55 to+/-90V 10Amax.

I see many similarities between PSU-10 and PSU-5,the differences are in voltage of zener-diodes,and parallel connections of the output transistors,also in input and output voltage. I don´t need that high output voltage as it in PSU-10,so PSU-5 is something that I would really like to built for myself ( I need adjustable power supply,to test all kind of amplifiers),but it hasn´t got enough power for my needs due to transistor´s low power limit. Could I add a pair of output transistors to PSU-5 (as it is in PSU-10) without other changes being made,in order to get higher current and power capabilities?

 

[apexaudio]

I see many similarities between PSU-10 and PSU-5,the differences are in voltage of zener-diodes,and parallel connections of the output transistors,also in input and output voltage. I don´t need that high output voltage as it in PSU-10,so PSU-5 is something that I would really like to built for myself ( I need adjustable power supply,to test all kind of amplifiers),but it hasn´t got enough power for my needs due to transistor´s low power limit. Could I add a pair of output transistors to PSU-5 (as it is in PSU-10) without other changes being made,in order to get higher current and power capabilities?

It's same schematics, just add a pair of outputs transistors to PSU-5 for 10A, and with low zener and input voltage this PSU can be use for class A amps like Hiraga.

 

[44250]

Well than that´s great! That is something I will built soon,thanks for sharing all this with us!

 

[MiiB]

The j-fet...are they complemtary...N and P channels for the posetive and negative part of the supply...

 

[apexaudio]

The j-fet...are they complemtary...N and P channels for the posetive and negative part of the supply...

No, all FETs are for CCS, and it's all N-fets BF245A.

 

[apexaudio]

Nice work Nikko!

3 x 1N4148 can be replased with the red led diode(Vf = 1.8V).

What is the voltage at the output when you turn on power supply and how much is after 10 minutes?

Yes, but LED need higher current than 1N4148 for Vref.

 

[DAMANHURI]

Dear Sir Mile, I have some problems in assembling the APEX-made power supply,
1. relay is not functioning at the time ON of the transformer is connected to AC 220V
2. I have a transformer 5 Ampere, 30V CT. Can I replace a few components that the module power supply is working perfectly ?
Please help Mr. Mile

 

[apexaudio]

Dear Sir Mile, I have some problems in assembling the APEX-made power supply,
1. relay is not functioning at the time ON of the transformer is connected to AC 220V
2. I have a transformer 5 Ampere, 30V CT. Can I replace a few components that the module power supply is working perfectly ?
Please help Mr. Mile

Replace 1k8/5W with 330R/2W

 

[tome]

Hi Mile
Do you have any regulated psu boards for sell (for power amp 10A and pre amp)
Puno hvala
tome

 

[44250]

Hi Mile
Do you have any regulated psu boards for sell (for power amp 10A and pre amp)
Puno hvala
tome

With some playing in "paint" it is easy to do. I will try to do it now... I did a mixture of a PSU5 and PSU10-using 12V zener(like in PSU5) and two pairs of 2SA/2SC transistors(like in PSU10) wich were connected to the board with wires as short as i could connect. Now it looks like this,and when i reach some inspiration and time,i will do it with new PCB. Anyway,there is one thing i must say:i have tested this PSU10,or should i say tortured it with 10A on each rail for one minute. 2x42VAC 450VA torus transformer was quite warmed up,uotput voltage dropped on 2x45VDC (due to transformer voltage drop) but the heatsink and output transistors not only survived it-they were slightly warm! Great thing!