jleaman said:
I just re-opened the other kit for scott, and it looks like his kit is all ok, so he has 6 p's and 6 of the others, Oh well. I'm not worried about my self, im only worried about him, Ill get some more and fix this all up
Thanks for your help guy's.
Jase
Give the guy who sold you the kit a call and explain what you're up against. He'll probably be more than happy to assist you.
jleaman said:
I just re-opened the other kit for scott, and it looks like his kit is all ok, so he has 6 p's and 6 of the others, Oh well. I'm not worried about my self, im only worried about him, Ill get some more and fix this all up
Thanks for your help guy's.
Jase
carpenter said:
Hi All,
Apparently I mixed up IRFP240 and IRFP9240 here. However if Jase got too many IRFP240, there will be someone that received only IRFP9240.
Jase...Did I mess up 1 or both sets? I will send the IRFP9240's that you miss. The least I can do after all the trouble you had.
Marcel.
Hi,
I have finished building a pair of F4 and am very happy with its sound. Just to share what my friend advised me while I was building the amps. Before soldering the Power FETs, it is good to do these checks:
1. Power the pcb with +/- 22V and check current of positive side about 11-12mA (LED 2.2mA + K170/J74 7-8mA, others 1mA). If the current is too high, your Jfet, TL431, diodes or zener may be reversed.
2. Check the two 10ohm source resistor of K170 and J74, it should be 7-8mA, voltage drop 70 to 80 mV.
3. Check the 10ohm resistor and C1/C2 point to see if the voltage is close to ground 0V.
4. Adjust P1 to full clockwise, the voltage between 240 gate and 9240 gate should be >8.5V, adjust P1 to full anticlockwise, the voltage between 240 gate and 9240 gate should not more than 7.5V. Keep the P1 full anticlockwise position which means that the bias is minimum.
5. At this stage, there is no need to adjust P2 for DC offset at output as there is no power mosfet and bias and the offset has to be adjusted with all that.
6. Then the pcb is ready to be mount on the heat sink and solder all the power mosfet. Make sure that 240 and 9240 is at correct position.
Best Regards
I have finished building a pair of F4 and am very happy with its sound. Just to share what my friend advised me while I was building the amps. Before soldering the Power FETs, it is good to do these checks:
1. Power the pcb with +/- 22V and check current of positive side about 11-12mA (LED 2.2mA + K170/J74 7-8mA, others 1mA). If the current is too high, your Jfet, TL431, diodes or zener may be reversed.
2. Check the two 10ohm source resistor of K170 and J74, it should be 7-8mA, voltage drop 70 to 80 mV.
3. Check the 10ohm resistor and C1/C2 point to see if the voltage is close to ground 0V.
4. Adjust P1 to full clockwise, the voltage between 240 gate and 9240 gate should be >8.5V, adjust P1 to full anticlockwise, the voltage between 240 gate and 9240 gate should not more than 7.5V. Keep the P1 full anticlockwise position which means that the bias is minimum.
5. At this stage, there is no need to adjust P2 for DC offset at output as there is no power mosfet and bias and the offset has to be adjusted with all that.
6. Then the pcb is ready to be mount on the heat sink and solder all the power mosfet. Make sure that 240 and 9240 is at correct position.
Best Regards
Banned
Joined 2002
carpenter said:
You're a decent fellow, Marcel. Being human, anyone can error.
I agree, every one makes mistakes, its just a simple one and i am VERY happy to see that you can help.
Scotts batch of fet's is perfect it has 6 IRFP9240's and 6 IRFP240's, it was just a coincidence i guess,
if you could send just one batch 6 of each that would be perfect Thanks.
Jase
Banned
Joined 2002
jleaman said:Its alive and noooo smoke
Jase
You're only going for a measly 400?
just kidding, work it up gradually.
Banned
Joined 2002
Banned
Joined 2002
carpenter said:... or perhaps a blast furnace?
I'm hoping to crank mine up a bit; at least the midbass units. The treble horns are 110db 1W1M and don't require more than a couple watts.
Good luck and do keep us posted. If I see a bright light in the sky out your way, I'll know that you went too far.
well my maximum Bias is 340mv. It wont go any further
( the pot starts licking meaning its at the end )Jase
Banned
Joined 2002
Banned
Joined 2002
Well was mostly just a joke. But something of the sorts. Solidstate is going to take place of everything eventually. Movies, Music even video games will move to solid state media. I'll only get digital media if its in HQ though which is very high quality MP3 rips (not your normal crap you get off itunes) or a lossless codec.
But my comment above was for fun and games
But my comment above was for fun and games