i got a hifonics amp was going into protect mode i replaced q7 and i think its q8 its the two common transistors on the driver board that usually fail the amp no longer goes into protect it idles at about 1.6 amp but nothing is coming out of the speaker im not sure where t start tracing the signal any help in the right direction would be appreciated
Do you have rail-rail oscillation on the output transistors?
Is the relay engaging?
Post photos of the main and driver board.
Is the relay engaging?
Post photos of the main and driver board.
yes the relay engages and im not 100% on how exactly to check for rail-rail oscillation i do have a scope
i dont think i fully understand where to probe from what i read the negative and positive on the output section were to be equal distance from the reference point on the scope
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There are only 3 terminals of the outputs. Probe all of them. Do you have rail to rail oscillation?
There are only 3 terminals of the outputs. Probe all of them. Do you have rail to rail oscillation?
you did reply i was asking about a specific type of amp and you said it may not be what i needed but ive been getting a lot more different types of amps so maybe it would be something i would benefit from
are you saying to put a multi meter on the legs of the output transistors im sorry this is still a little new to me
are you saying to put a multi meter on the legs of the output transistors im sorry this is still a little new to me
You said you had a scope. Use that to look for rail-rail oscillation. It will look like the example.
The tutorial is for those willing to put forth the effort to study (hard) to learn about a lot of different types of amps. Nowadays, there are few willing to do anything more than to watch a video. That's why I stopped adding to it.
The tutorial is for those willing to put forth the effort to study (hard) to learn about a lot of different types of amps. Nowadays, there are few willing to do anything more than to watch a video. That's why I stopped adding to it.
i still dont know where exactly i need to place the probe if your full version tutorial explains this in detail i will purchase it i have no problem educating myself this by far not the last amp i will be working on
What scope do you have so we know what you are looking at? Scopes are quite a large learning curve if you are new to them.
Does the drive board get warm when you power the amp?
Also, do you have your rail voltage at the rectifiers and control voltage from the transformer?
Does the drive board get warm when you power the amp?
Also, do you have your rail voltage at the rectifiers and control voltage from the transformer?
the drive board gets warm where they all typically do i replaced the two faulty transistors on it it gets warm in the upper top right corner
You stated that you had rail voltage that was equally far from the center reference. With that same vertical amplifier setting, and the timebase set to 5us, probe all 3 legs of the output transistors. Some will have the rail voltage that you saw previously. The others will have no voltage, rail-rail oscillation or some level of DC.
For now, if you want to read up on scopes and basic usage, read page 73 of the bcae1.com site.
For now, if you want to read up on scopes and basic usage, read page 73 of the bcae1.com site.
on the first half of the irf640n the ones towards the center the two outside pins have a square wave the last set of three towards the outside of the board the center pins have the square wave then the two outside pins have the equal voltage from center reference
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