500W PA amplifier with Limiter

[apexaudio]

Your work can help to other diyers without expirience to not be afraid to build their own amplifier, somethimes only soldering is needed (if someone build and test amplifier circuit before you), and learn ohm's law.
Regards

 

[eesbiboi]

This math is correct, and you must use it in electronic, it's basic math not high school,
Regards

hey what do ya say!!!...i got it right!!!...
cheers to me...

then my trafo would 50v+50 x 20amps=2000va!!!...

 

[AndrewT]

without an understanding of Ohm's Law one cannot specify the fuse for a piece of equipment.
Without arithmetic one can forget about following a schematic.

Without arithmetic one can never get beyond copying someone else's explicit instructions.

 

[Tube Pro]

it's not that i really hate math very much...i just dont like counting NUMBERS...
but for sure, i love to solder...

hahaha.
Hi Ees,
you should love mathematics.
Electronics is full of complex numbers...


Good Luck

 

[eesbiboi]

hahaha.
Hi Ees,
you should love mathematics.
Electronics is full of complex numbers...


Good Luck

basic math is what i have...
i dont do amp math...jeje
as you said earlier...it's very complex...
makes my head go round and round...

 

[rhodrich]

eesbiboi,

what kind of amp you used on your subwoofer? and what kind of speaker inside

 

[eesbiboi]

eesbiboi,

what kind of amp you used on your subwoofer? and what kind of speaker inside

local diy amp is what i use for my low freqs...jH 181 crown...

 

[hamub]

Transformer

if i use it with the b500 how much power can i get considering that after rectifying its gonna be something like 45-0-45. I want to use this transformer till i get a good one

is it ok for this transformer which i rewound the secondary to draw a current of 1.7AMPS at the primary when not loaded for a 220 volts supply. I connect my ammeter in series.

 

[apexaudio]

is it ok for this transformer which i rewound the secondary to draw a current of 1.7AMPS at the primary when not loaded for a 220 volts supply. I connect my ammeter in series.

Transformer efficiency is 98%. That mean lost 2W per 100W power.

 

[hamub]

Transformer efficiency is 98%. That mean lost 2W per 100W power.

hie Miles, i was asking that is it ok for my transformer to draw 1.7 amps when nothing is connected at the secondary?

 

[AndrewT]

1.7A when on no load equates to 374W for zero secondary output.
That 374W must escape as heat.

I do not believe that the 1.7A figure has been measured correctly.
It cannot be right. The transformer would be smoking, or worse, if it was dissipating 1.7Aac @ 220Vac

 

[hamub]

1.7A when on no load equates to 374W for zero secondary output.
That 374W must escape as heat.

I do not believe that the 1.7A figure has been measured correctly.
It cannot be right. The transformer would be smoking, or worse, if it was dissipating 1.7Aac @ 220Vac

the figure is correct Andrew. This tx is as cold as the antarctic. I took it from a microwave oven rewound it to give 32-0-32 at the secöndary. I did not wind the primary.

 

[smeegle0218]

1.7A when on no load equates to 374W for zero secondary output.
That 374W must escape as heat.

I do not believe that the 1.7A figure has been measured correctly.
It cannot be right. The transformer would be smoking, or worse, if it was dissipating 1.7Aac @ 220Vac

don't forget the P.F. (power factor). an unloaded transformer acts as an iron cored inductor, so most of the 374VA are VARs not watts. And it is the few watts that will contribute to the heating.

 

[apexaudio]

the figure is correct Andrew. This tx is as cold as the antarctic. I took it from a microwave oven rewound it to give 32-0-32 at the secöndary. I did not wind the primary.

Andrew is right, if tx is cold after 10min. current measure is incorrect, and you can use it,
Regards

 

[hamub]

Andrew is right, if tx is cold after 10min. current measure is incorrect, and you can use it,
Regards

alright thanks guys. I will check my measurements again and try to give the tx more time to see if he doesnt heat up. Maybe my analogue meter is lying. But thanks guys esp Mr Miles for an excitin thread.

 

[coolet]

Hi Apex,

Is this correct? You got PM

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

 

[apexaudio]

You need +/-45V on +MV/-MV. Colectors of MJE15032/MJE15033 must be connect to colectors 2SA1943/2SC5200, see post #402 in thread:
http://www.diyaudio.com/forums/solid-state/162408-900w-h-class-pa-amp-limiter-41.html
Regards

 

[engel dela pena]

Hi Apex,

Is this correct? You got PM

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

hope this helps

 

[coolet]

@ apex tnx got it )

tnx Angel.. I'll make a new layout

so what is the +/-MV voltage? for B500

 

[engel dela pena]

@ apex tnx got it )

tnx Angel.. I'll make a new layout

so what is the +/-MV voltage? for B500

sorry for my lines
hope this make sense
apex pls. correct me if i'm wrong