MOSFET Amplifier IRFP240/IRFP9240

These are the pictures
 

Attachments

  • 25062012116.jpg
    25062012116.jpg
    490.3 KB · Views: 1,600
  • 25062012117.jpg
    25062012117.jpg
    538.9 KB · Views: 1,408
  • 25062012118.jpg
    25062012118.jpg
    508.4 KB · Views: 1,211
  • 25062012119.jpg
    25062012119.jpg
    496.6 KB · Views: 1,035
irfp

Hi all, i`ve made this amp,(hv350.2) and i would like to say that is working perfectly, clip works like a charm.I would like to build second module, but i have run out of 0.47r/5w, what component i have to change to put 0.33r/5w, because i have a bounch of those.
I whant to say thank you to apex for sharing this amp with us.Thank you in advance for your advice
 
Hi all, i`ve made this amp,(hv350.2) and i would like to say that is working perfectly, clip works like a charm.I would like to build second module, but i have run out of 0.47r/5w, what component i have to change to put 0.33r/5w, because i have a bounch of those.
I whant to say thank you to apex for sharing this amp with us.Thank you in advance for your advice

Can you post pictures of your HV350.2 ? You can use 0.33R/5W without changes.
 
irfp

Sure apex I`ve uploaded a couple of them here Pictures by zighi202 - Photobucket Ive made the other module with 0r33.Works perfectly, clip and everything.I,ve made the regulated psu you shared with us, and i`ve set 60 volts for start.I`ve managed to make a pcb for regulated psu with 4 pairs of outputs, i think is enough for 2 modules.I will share that pcb but only after i had test it.(if somewone whant it ofecurce)
For tuning i`ve set bias using a 10r resistor insted of a fuse in rail, and i have set 2 volt trough it.
Ofecuorce i will make a protection too.If you have some more advice to modify something, or to do something diffrent i am open to it.

have a nice day all.
 
Sure apex I`ve uploaded a couple of them here Pictures by zighi202 - Photobucket Ive made the other module with 0r33.Works perfectly, clip and everything.I,ve made the regulated psu you shared with us, and i`ve set 60 volts for start.I`ve managed to make a pcb for regulated psu with 4 pairs of outputs, i think is enough for 2 modules.I will share that pcb but only after i had test it.(if somewone whant it ofecurce)
For tuning i`ve set bias using a 10r resistor insted of a fuse in rail, and i have set 2 volt trough it.
Ofecuorce i will make a protection too.If you have some more advice to modify something, or to do something diffrent i am open to it.

have a nice day all.
You should add some more soldier to power traces,otherwise it looks great! How does bias current behaveing? On HV23 it starts with about 100mA per pair and it quickley goes down to about 20mA per pair as the heatsink goes warmer.
 
Apexaudio, thanks for sharing, but I think if you expected to come here, put your design on display (and perhaps sell some PCBs) and get universal praise for your design and think that because it has been in use for 10 years that it cant be improved on, you are mistaken. these guys are not criticizing, they are bouncing ideas to improve the circuit around. there are some serious pros here, in general the attitude here is a proactive one, no need to be defensive. if you dont want constructive criticism, I have to wonder why you posted...... take it on board; or not. up to you

Apex knows what you and your side kicks are like . I do too. you are here comericially apex is not . you call your attitude proactive i would call it somthing else . PS we all know your designs are the best NOT. Stop wondering as it has no place in DIYAudio!!!!!!!!.
G,Day Ripper
 
APEX with 2SA1943/2SC5200 bipolar output tranzistors

In last tree years in my PA amplifiers I use new design with 2SA1943/2SC5200 bipolar output tranzistors and IRF2807 mosfets for step. Amplifier work in H class 0,+/-60V,+/-120V.

Good morning.
I appreciate your good work and great experience in this matter.

So, You mentioned you have a new design of APEX with 2SA1943/2SC5200 bipolar output tranzistors.

Where I can to find the scheme, hints and pcb's for this design?

I mean to try to build just such model, because I have several pieces of this transistors type. Besides I do not want to make an error in the calculation because a wrong trial always leads to destroy the semiconductor.

I'll gratefull for your help and a quick reply, even to my private mailbox - bionix_at_bionix_dot_vel_dot_ pl

Sincerely
Ted Jako
 
Last edited by a moderator:
i didny have much time to read all the posts on this thread. what i just need is help on determining the bias voltage accross r20 and p1 or accross one of the 0.47ohm resistors which gives the 30ma bias current.

1-connect input gnd to power supply gnd. then check the dc offset.
2-bias adjustment, 10mv across 0.47 emitter resistor .
 
Last edited:
1-connect input gnd to power supply gnd. then check the dc offset.
2-bias adjustment, 10mv across 0.47 emitter resistor .

U= 0,01V
R= 0,47Ohm

I=U/R= 0,01/0,47= 0,021 (2765957...) A =21mA

???

For 30mA in 0,47Ohm by mr.Ohm it would be

U= R x I = 0,47 (Ohm) x 0,03(A) = 0,0141V = 14,1mV

Come one,if i know that than it can not be more coplexed than second year of hi-school -why it is so difficult to calculate-not just for you but for many teenagers today? Freaken computers will make a robots from us...
 
Last edited:
Thanks pipo but I have observed that we have two figures, 14.1mv and 10mv. So which is which here?

And also I have a 44-0-44 toroid transformer in ma possession and I want to use it on the hv23. The dc voltage is lower than the specified 75-0-75 in the hv23. Now the current is what I don't know about. All there is is that two 1mm thick wires were wound as a pair for the secondary. Need help on this as well.