DIGI-125 Kit Amplifier Module

[AKSA]

Rakesh,

Should be fine. You will have around 40V rails, which is fairly high for a single pair of outputs, the drivers will both be fine but I'd be tempted to use a faster transistor for the voltage amp - again a TO126, something like a BF469 would do nicely.

Cheers,

Hugh

 

[mrfeedback]

Hello Rakesh, as Hugh says, good work, however......
I would shift the speaker return to 5mm above the Com connection and put the 0.1 decoupling caps just above the diodes.
Ditch the led's and make the earth land wider so that the input ground and the C1 10uF/63V cap can have their individual earth connections - the ground for that NFB shunt cap is critical and should not be tangled with any other earth currents.
Also the input is shorted to ground !.
Also shift the output connection up to the middle of the land, and the R5 connection down.

Keep up the good work,
Eric.

 

[rakesh_sharma23]

Many thanks ..
As per transistor for the voltage amp, initially start with BD139 and will replace it with BF469.

will update layout soon..

Rakesh Sharma

 

[wakwakni]

hi,

Can i use this with my 2x24vac 15 amps transformer?

How many digi-125 amplifier can be connected?

i have 10 pairs of 4700 uf/50v

Do i need to put a dc protect in each amp?

I planning to make a multi channel system..

thanks.

 

[rakesh_sharma23]

One more question... Can IN4148 be used instead of IN914 ?

 

[AKSA]

Yes, absolutely....

Hugh

 

[rakesh_sharma23]

Thank you very much Sir.

All parts are in, now first will make one amp and test it .. then make five more for my 6 Channal amp build.

 

[wakwakni]

Thank you very much Sir.

All parts are in, now first will make one amp and test it .. then make five more for my 6 Channal amp build.

Rakesh, how many amps and how many volts (secondary) in your transformer?

 

[rakesh_sharma23]

Six Channal Amp with 27-0-27 AC 8amp Transformer.

 

[wakwakni]

Six Channal Amp with 27-0-27 AC 8amp Transformer.

thanks rakesh... i will try to build one too.

maybe my 15 amps transformer will be alright.. with 5 channels

 

[rakesh_sharma23]

Nice to hear that Sir,,
Are you planning to use single or multiple PSU ..
I am using one PSU per AMP.... made on same PCB..

 

[rakesh_sharma23]

Test Amp construction under process...

 

[wakwakni]

Nice to hear that Sir,,
Are you planning to use single or multiple PSU ..
I am using one PSU per AMP.... made on same PCB..

sir i'm planning to use 1 psu for all the amps. but is it ok with same transformer?

sir what is the size of your pcb?

 

[wakwakni]

Test Amp construction under process...

nicely done.

 

[rakesh_sharma23]

sir i'm planning to use 1 psu for all the amps. but is it ok with same transformer?

sir what is the size of your pcb?

I think its ok to power all amp with one single transformer and multipal PSU Circuit.. Until and unless tranformer have that much juice..
PCB Size = 7cm x 5.5cm
Work under progress

 

[wakwakni]

I think its ok to power all amp with one single transformer and multipal PSU Circuit.. Until and unless tranformer have that much juice..
PCB Size = 7cm x 5.5cm
Work under progress

thanks sir..

have u tested your unit?

 

[rakesh_sharma23]

Tested the amp..

Audio source.. PC -Asus Xoner DX2 sound card...

Very nice and rich sound quality ... I was missing this type of musical sound...

Thanks for sharing a simple and quality amp...

Rakesh Sharma

 

[norvbul]

Test Amp construction under process...

Could you post the component overlay for your board.

 

[rakesh_sharma23]

Could you post the component overlay for your board.

Sure Sir.

 

[gless]

Can i use BC639 instead of BC546/BD140, and BC640 instead of BC556/BD140. BC546-556 out of stock and i can't find BD139-140 here. They are almost the same as BD139-140 in the datasheet.