Good morning DIY audio peoples it's been awhile since I've been on here and have a new project. Have MTX ta 92001 that has output but the LED lights on the top of the unit are not lighting up. the output is very distorted and staticy the first initial base hit of the music note played good, every note after that tends to wash out and sounds very staticky as if it's losing power open up the unit. The little corrosion by the large capacitors by the output terminals . also the two large inductors by the power input or buzzing really loud. LED light behind the RCA inputs are not lit up but the LED light by the output inductors top left corner are on. what do y'all think about issue might be? or where to start, the and work perfectly fine before the winter has been stored out in the garage in the Chicago weather for the winter time now this issue is present.
thanks.
thanks.
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Sounds like one of the regulators went bad .
Do you have both positive and negative 15 volts on all of the opamps ?
Do you have both positive and negative 15 volts on all of the opamps ?
Nope. Only getting 13.06positive negative all the op amps except for the ones that are by the ribbon cable connector for the preamp board those two are only showing 4.60. the resistor by the capacitors are 4082 is getting very hot not smoking but very hot almost to the point to where you cannot touch it. The two inductors have stopped buzzing barely warm to the touch.
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Does the voltage on the op-amps change if you disconnect the preamp board?
Do you operate this amp without having all of the regulators tightly clamped to the heatsink. They can fail within seconds, doing severe damage.
Do you operate this amp without having all of the regulators tightly clamped to the heatsink. They can fail within seconds, doing severe damage.
Pre-amp board was disconnected doing the testing. All regulators and mosfets are clamped down. Had the same. issues in the past for a different mtx amp, if there not clamp down
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Ok I cleaned up all the corrosion that was on the board the two inductors by the power input aren't buzzing no more, but now I'm getting 26 DC voltage out of the speaker terminals with no RCA's plugged up nor speakers
N5534 op amp starting with the op amp closest to LED 400
Pin 1 11.87
2 11.18
3 12.17
4 -15.01
5 -14.16
6 -13.40
7 15.11
8 15.09
Op amp farthest from led 400
Pin 1 11.87
2 2.46
3 1.88
4 -15.00
5 14.26
6 -13.41
7 15.11
8 15.09
Pin 1 11.87
2 11.18
3 12.17
4 -15.01
5 -14.16
6 -13.40
7 15.11
8 15.09
Op amp farthest from led 400
Pin 1 11.87
2 2.46
3 1.88
4 -15.00
5 14.26
6 -13.41
7 15.11
8 15.09
The op-amp nearest the LED appears to be defective. With the non-inverting input higher than the inverting input, the output on pin 6 should be high, not low.
Cool beans. What's a good replacement op-amp for it? I think I have a few NE5532 or N5532 but no N5534 in right now.
I replace both op amps that are by led 400. The two large inductors by the power input are buzzing again but now I have 23 volts DC on the speaker output instead of 26.What is the value of the op amp that is located right in front of the RCA input.i have -15 and 15 volt at the op-amp by the RCA inputs but all the other pins show zero
The voltages you posted for the op-amps indicated that one was bad. Repost the voltages for those two op-amps.
It's normal for most of the op-amps to have 0v on all but the power supply pins.
It's normal for most of the op-amps to have 0v on all but the power supply pins.
Tl494c over by the inductors when I press it with my finger or tap on it the buzzing noise pulses and changes notes could there be something wrong with this semiconductor?