I don't have a 300/2 here but the 500/1 I have here has a very similar circuit and the FET (IRFZ44) runs cool. Measure the voltage across the 33 ohm resistor near the transformer. This amp has 3v DC across the 33 ohm resistor. Yours should have something similar. If it's significantly more, there may be a problem.
If you have a scope, measure the peak voltage of the gate drive signal on Q510. If I'm not mistaken, your amp uses the 3843 driver IC. If so, you should see a drive signal of ~10v peak.
The 4 amps of current draw could be from the biasing of the audio amplifiers. Before you try adjusting them, measure the DC voltage across the test points. Be careful not to allow the probes to contact the busbars.
If you have a scope, measure the peak voltage of the gate drive signal on Q510. If I'm not mistaken, your amp uses the 3843 driver IC. If so, you should see a drive signal of ~10v peak.
The 4 amps of current draw could be from the biasing of the audio amplifiers. Before you try adjusting them, measure the DC voltage across the test points. Be careful not to allow the probes to contact the busbars.
I´m back!!!
Yes, have a problem, one side has 11.13V and the another side 14.4V
this is the wave form from the gate of Q510 set at 5us and 5v.
This is from the Drain:
And the source:
The + - 53V its ok
+ - 15 is now + - 17V, but I think it´s by the actual failure.
another comment: the two IC 74VHC132 are very hot.
Perry Babin said:
Yes, have a problem, one side has 11.13V and the another side 14.4V
You are right, it use the 3843BPerry Babin said:
this is the wave form from the gate of Q510 set at 5us and 5v.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
This is from the Drain:
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
And the source:
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Perry Babin said:
The + - 53V its ok
+ - 15 is now + - 17V, but I think it´s by the actual failure.
another comment: the two IC 74VHC132 are very hot.
JL Audio 300/2 fets
Perry,
Thank you for your reply. The reason I ask this question is because the IRF540 is rated for 100 Volt , 28 Amp , and 150 Watt.
The IRF 540N is rated at 100 Volt 27 Amp and 94 Watt.
I did not notice this till after I had removed all 8 of them. If this is not that much of a differance in there values I my have other problems.
Steve
Perry,
Thank you for your reply. The reason I ask this question is because the IRF540 is rated for 100 Volt , 28 Amp , and 150 Watt.
The IRF 540N is rated at 100 Volt 27 Amp and 94 Watt.
I did not notice this till after I had removed all 8 of them. If this is not that much of a differance in there values I my have other problems.
Steve
Were the IRF540Ns in the amp originally?
The specs vary by manufacturer. The following is the datasheet for the International Rectifier IRF540N:
http://sigma.octopart.com/49860/datasheet/International-Rectifier-IRF540N.pdf
What sort of problem are you having?
The specs vary by manufacturer. The following is the datasheet for the International Rectifier IRF540N:
http://sigma.octopart.com/49860/datasheet/International-Rectifier-IRF540N.pdf
What sort of problem are you having?
No, the same problem when I star this tread...
It ignites of intermittent way.
turn´s on 15 seconds and turn´s of 5 seconds, turn´s on 15 seconds and turn´s of 5 seconds, etc.
Star drawing .6 amps and in teen seconds the amp draws 10 amperes for after shut down and star again in .6 A
It produces during few seconds audio in two channels and Bridget.
During this time left channel is 0.1 V DC and right channels is .01 V DC
Another: when I remove remote cable the amplifier continue drawing .5 A
Note: All the mosfets are new and original.
¿Do you want to see a video of this?
It ignites of intermittent way.
turn´s on 15 seconds and turn´s of 5 seconds, turn´s on 15 seconds and turn´s of 5 seconds, etc.
Star drawing .6 amps and in teen seconds the amp draws 10 amperes for after shut down and star again in .6 A
It produces during few seconds audio in two channels and Bridget.
During this time left channel is 0.1 V DC and right channels is .01 V DC
Another: when I remove remote cable the amplifier continue drawing .5 A
Note: All the mosfets are new and original.
¿Do you want to see a video of this?
Yes Perry, the previous mosfets appear be fine whit the multimeter, but I has the doubt, for this reason I changed all the mosfets new and original.
If the amplifier isn´t ready for 16 September , the dynamite-amplifier can be their work and help to celebrate the Mexican independence.
If the amplifier isn´t ready for 16 September , the dynamite-amplifier can be their work and help to celebrate the Mexican independence.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
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