900W H-class PA Amp with Limiter

[irvynejay]

@crazymechanic s ground and main ground should be connected to main psu ground

@Djnits pls post photo something is wrong on your step drive high side negative rails is keep triggering

@ryanda 1n4148 is not good replacement of BAV21 use mur120

 

[Djnits]

@crazymechanic s ground and main ground should be connected to main psu ground

@Djnits pls post photo something is wrong on your step drive high side negative rails is keep triggering

@ryanda 1n4148 is not good replacement of BAV21 use mur120

sir irvynejay here the pic of my h900

 

[apexaudio]

sir irvynejay here the pic of my h900

BF421 is PNP transistor, use MPSA92 insead BF421 not MPSA42 (NPN) !

 

[Djnits]

BF421 is PNP transistor, use MPSA92 insead BF421 not MPSA42 (NPN) !

thanks sir apex, posible it's the cause of my problem.

 

[irvynejay]

Djnits yes its possible because you use npn instead of pnp

don't forget S ground and main ground connected to main psu with separate wires

 

[apexaudio]

thanks sir apex, posible it's the cause of my problem.

And don't forget wire jumper.

 

[Djnits]

Djnits yes its possible because you use npn instead of pnp

don't forget S ground and main ground connected to main psu with separate wires

thanks sir irvynejay and sir apex for your advice


Regards

 

[ravpreet420]

apex 30/50hz filter

thanks...........

 

[Djnits]

And don't forget wire jumper.

hello sir apex and irvynejay still the same my problem, i had all ready change the transistor, of ksp92 PNP, please see my attach pic.

 

[irvynejay]

can you pls check you fets if its not shorted,, pcb pattern possible for short

 

[Djnits]

can you pls check you fets if its not shorted,, pcb pattern possible for short

thanks for your responce, but i had all ready double check the pcb sir, not posible the direction of sfa1603, if i make to reverse this no problem?

Regads

 

[irvynejay]

comulator (fmxg12) diode is correct position high rail only trigger when step is working at high gain there's wrong something with you parts


gate voltage is too high make sure fets is not busted

 

[Djnits]

comulator (fmxg12) diode is correct position high rail only trigger when step is working at high gain there's wrong something with you parts


gate voltage is too high make sure fets is not busted

thanks sir jay, i had all ready solve my problem w/ you help, there's a problem w/ my circuit at mosfet. two thumbs up sir jay and apex thanks.

Regards

 

[irvynejay]

ok good to know that ,,have fun Bro

 

[Djnits]

ok good to know that ,,have fun Bro

thanks irvynejay, and i want share this problem, to help some diyers to be careful of there project and double check, my circuit its look good or no short, but when i check it by tester totally short circuit, please see my attach pic. thanks w/ the help of sir irvynejay and sir apex,

 

[irvynejay]

Pls check pm ty

 

[ryanda]

@crazymechanic s ground and main ground should be connected to main psu ground

@Djnits pls post photo something is wrong on your step drive high side negative rails is keep triggering

@ryanda 1n4148 is not good replacement of BAV21 use mur120

thank's Irvy,..my h 900,.. transistor mje 340 and mje 350 is hot.,.my rail voltage is..80 40 0 40 80 VAC,.whats wrong for this?

 

[Djnits]

Pls check pm ty

Thanks , i will

 

[apexaudio]

thank's Irvy,..my h 900,.. transistor mje 340 and mje 350 is hot.,.my rail voltage is..80 40 0 40 80 VAC,.whats wrong for this?

Nothing wrong, MJE340/350 work in class A and disipate 1W without signal on amp input, use heatsinks for MJEs.

 

[ryanda]

Nothing wrong, MJE340/350 work in class A and disipate 1W without signal on amp input, use heatsinks for MJEs.

thank's for sir apex..and now for triple darlington where is the better,..in base i'm put resistor 3,3ohm or without resistor..