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T.amp TSA 4-1300 Power Amplifier Issue: Not Turning On, Red Diode Flashing, No Visible Damage

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Treść została przetłumaczona polish » english Zobacz oryginalną wersję tematu
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  • #331 21384014
    aaanteka
    Level 42  
    Well maybe your theory would be right in the use of a conventional power supply and a terminal stage supplied with a single voltage.
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  • #333 21385543
    Robercikxxx
    Level 15  
    I don't know what you're taking, but you'd better put it down.
    What's the difference if the power supply has one voltage or ten. If the fuse on the primary side blows, i.e. as I did at +320V DC, all the voltages will be switched off. That is, as if you were simply switching it off with a switch or unplugging it from the socket. You have some strange Chinese theories. Tell me exactly what you mean and explain it sensibly, because I don't understand you. I'm probably not smart enough to understand you. Even by simple logic, a fuse blows and everything shuts down. In your opinion, is it better that it is not there and the transistors blow? And burn more components behind them ?
  • #334 21389822
    jeanbernardsers
    Level 5  
    Hi I've tried to quickly draw the IRGP command circuit - please find below my drawing - maybe there are a few errors, I did not draw all the wires, but the main purpose is there : when LM339 output is high, the LM555 pin 3 can be at 0v, the SG3525 can start oscillating providing Out A and B to the two IR2110S. PS : did not draw the viper part, providing 17v. By the way some "?" to mean "I don't know more" or "not very sure".
    So I hear the self starting then stopping every 10 sec, with my test bulb lighting quickly for each start (so once every 10s) - will check without the IRGPs ...

    Circuit sketch with LM339, LM555, SG3525, and IR2110S chips and IRGP4066D transistors.
  • #335 21390020
    Robercikxxx
    Level 15  
    What wattage of bulb?
    What voltage do you have on these points ?
    Multimeter measuring voltage on a PCB, displaying a reading of 6.87. .
    Close-up of an electronic circuit with a meter showing voltage of 6.96 V. .
    A hand holding a multimeter probe touches a point on a circuit board, with the multimeter display showing a reading of 6.96. .
    Voltage measurement on a green circuit board using a probe and a meter displaying 6.55 V. .
    Printed circuit board with a multimeter showing a reading of 6.55 V. .
    Digital multimeter showing 5.64 V voltage reading on a circuit board, using a probe. .
    Voltage measurement on a circuit board using a multimeter. .
    Voltage measurement on a circuit board using a multimeter. .
    A red multimeter probe touching a circuit board next to a multimeter display showing 16.81 V. .
    Measuring voltage on a circuit board with a multimeter. .
    Voltage measurement on a circuit board with a multimeter. .
  • #336 21390436
    Robercikxxx
    Level 15  
    On which mileage you have , take a picture and mark it.
  • #337 21390142
    jeanbernardsers
    Level 5  
    I will try later thank you. I've changed again the two 2110 and now I have square but only on two IRGPs. On your picture, is it normal that only 2 IRGPs are soldered ?
    Can you show me the signals you have on the 4 gates of 4 IRGPs please ?
    Thanks again

    Added after 11 [hours] 25 [minutes]:

    Sorry, I did not see that your measurements were on the four gates. I've unsoldered all IRGPs - should I solder at least two IRGPs as on your picture to mes the gate voltage ?
    My bulb is 160W (actually, two bulbs : 100W + 60W).

    Added after 1 [hours] 20 [minutes]:

    So here is out A and out B signals
    Oscilloscope screenshot showing two square wave signals in yellow and pink.
    voltage measured :
    SG 3525 :
    - pin 16 = 5v
    - pin 13 = 17v
    pin 10 = 0,11v
    pin 9 = 5,69v
    IRGPs see picture :
    top IRGP (gate D753/R753) : squared signal in yellow (following Lo signal of IR2110 U4 )
    bottom IRGP (gate DD750 R750): opposite squared signal in pink (following Lo signal of IR2110 U5) :
    Oscilloscope display with square wave signals in yellow and pink.

    but on the two gates of the two others IRGP (from HO of the two 2110), I have a constant 14v voltage.
    Once again, the 4 IRGPs are unsoldered during these measurements.
    Any advice ?

    Added after 7 [hours] 9 [minutes]:

    Hi - I've modified the schema :


    Electronic circuit diagram with components LM339, LM555, SG3525, and IR2110S.
    And after having soldered only Q192 and Q194, I had the following signals :


    Oscilloscope displaying voltage signals at transistors Q192 and Q194.
    Oscilloscope screen with signal waveforms and circuit schematic.
    Oscilloscope displaying signals on transistor gates in an electronic circuit.

    So before soldering Q 191 and Q193, I wonder if those signals seem to you ok as they are not very proper square signals, with bouncing at the rising edge of Q191 and Q193, but maybe it's because Q 191 and Q193 are not soldered and so no C179 and C177 filtering cap.

    What do you think ?
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  • #338 21391951
    Kawaiito
    Level 4  
    Hello I have the problem with repairing one 4-300. It's the similar same structure like the 4-1300. Supply works but always the voltage on the relais (ground) drops all 10-20 seconds to 3-14V and the amp goes in loop to protection with the relais. I test with my scope on 1kHz input and measure before the relais and there works all fine. I test all darlington transistors/diodes with the multimeter and don't see any failed capacitors. But without circuit schematic it is so hard to follow the very small conductor tracks to understand the circuit. Does everyone have the same problems on repair?
  • #339 21400822
    aaanteka
    Level 42  
    Robercikxxx wrote:
    Professor what exactly you mean and explain it sensibly because I don't understand you. I don't think I'm too clever to understand you. Even on simple logic , a fuse blows and everything shuts down.
    .
    Well the basics of DC circuits bow. Your logic is a flawed logic assuming that if you break a DC circuit with a semiconductor controlled impedance load, all current stops flowing in the circuit immediately. When you add to this the principle of the secondary side power supply to the load you have the full answer.
    It is also interesting to note the type of fuse used in this circuit. Any particular product? How did you select its parameters and according to what?

    Another aspect is that all designers of similar solutions do not use this type of protection.
    - I wonder why?
  • #340 21433526
    Kawaiito
    Level 4  
    so i got my 4-300 TSA working .. it is normal the MJD350 for the -15V is basically hotter than the MJD 340 for the positive 15? have no one the same the newer revisions have LM's for this
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  • #341 21433599
    Robercikxxx
    Level 15  
    They don't use these solutions for a very simple reason. The equipment is supposed to break down after a while and it is supposed to be so damaged that you have to go to the shop and buy a new one and not repair the old equipment. But no matter. I can see that you are not going to get over it anyway. Even though you have one, others have another.

    Added after 2 [minutes]:

    >>21433526 .
    What difference does it make how it heats up. If it's -15V and +15V then you need to look elsewhere. Also, what is going on with your amp ?
  • #342 21438211
    aaanteka
    Level 42  
    But it is the bizarre structure in question that is something wrongly designed that cannot be improved , no matter how hard we try.

    And the solution indicated above is completely unwarranted and may do more damage than good. A hint as to why has already been given above.
  • #343 21438226
    Robercikxxx
    Level 15  
    All right, that is your opinion and mine is different. I know that if I install a fuse, it will be better than not having one. You may have a different opinion, and I have no problem with that.
  • #344 21438236
    aaanteka
    Level 42  
    Let me put it this way, the role and parameters of the fuse in general are treated too superficially or ignored altogether. The fuse is not a perfect component and cannot be used interchangeably in different circuits without real consequences.
  • #345 21438557
    398216 Usunięty
    Level 43  
    I think there was a segment on the RS Electronics channel (or the twin Noise Reducer) about fuses . I would advise unbelievers to look for it and, after watching, to consider whether Col. aaanteka is right or wrong.
    You can really learn a lot of interesting things.
  • #347 21475669
    gaspixx
    Level 3  
    Hello all,
    can I use 2x24VAC to power up the 'P' circuit with 15 and 24v stabilizers for the test? I tried 2x15VAC transformer today and got only 20VDC on the input of 7824. 7915 is okay (-15VDC) 7815 had only 12v at output. All red LEDs were on.
    Thank you
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Topic summary

The T.amp TSA 4-1300 power amplifier exhibits a failure to power on, with a flashing red diode near the capacitors and no visible physical damage. Investigation revealed multiple damaged IRGP4066D IGBT transistors on the primary side inverter, along with damaged power transistors (NJW0302GC), MOSFETs (GP105N15M), rectifier bridges (GBJ3006SF, 2506SF), and driver ICs (IR2110S, SG3525A). The amplifier uses a full-bridge power supply topology operating around 85-100 kHz with multiple symmetrical voltage rails (+/-15V, +/-40V, +/-60V, +/-90V, +/-160V) for preamplifier and power amplifier stages. The power supply design lacks galvanic isolation, current limiting, and effective overload protection, leading to frequent IGBT and associated component failures. SMD components such as EF8 and T4/H5 diodes (likely Schottky and Zener types) near the inverter and driver circuits are critical and often damaged. The triac (BTA41-600B) controlling AC mains to the rectifier bridge is also a common failure point. Repair attempts require replacing IGBTs, driver ICs, rectifiers, and passive components, but without a schematic or service manual, troubleshooting is challenging. Oscilloscope measurements of PWM signals and gate drive waveforms are essential for diagnosing dead time and control issues. Some users suggest replacing the entire power supply with a custom design due to the amplifier’s complex and failure-prone power stage. The amplifier chassis serves as a ground connection, which must be properly connected during bench testing. Auxiliary power supplies (e.g., 2x12V AC transformers) are used to test amplifier channels independently. Despite extensive repairs, issues such as persistent fault LEDs, relay non-activation, and channel-specific transistor failures remain common. The amplifier is considered difficult to service due to integrated power and control boards, lack of documentation, and complex SMD circuitry. The original design is reportedly based on the Chinese Leicozic DP41200 amplifier. Community consensus highlights the need for careful component verification, replacement of damaged SMD diodes and resistors, and cautious startup procedures using current-limited power supplies or light bulbs to prevent repeated damage.
Summary generated by the language model.
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