Hi
I need some help with this amp. What is the bias setting for this amp. The schematic shows SVR302 as the bias pot, but it does not show the voltage or the bias points. Across which component or point do I take the bias voltage reading. One more issue is that, the transistors Q304, Q305, Q306 and Q307 are getting very hot when the amp is turn on. Is this normal, but the driver and power transistors are just warm. I amplifier is working fine, just what is bugging me is why just this 4 transistors are getting so hot. Is it normal and OK for them to get hot. Please assist.
Thanks
I need some help with this amp. What is the bias setting for this amp. The schematic shows SVR302 as the bias pot, but it does not show the voltage or the bias points. Across which component or point do I take the bias voltage reading. One more issue is that, the transistors Q304, Q305, Q306 and Q307 are getting very hot when the amp is turn on. Is this normal, but the driver and power transistors are just warm. I amplifier is working fine, just what is bugging me is why just this 4 transistors are getting so hot. Is it normal and OK for them to get hot. Please assist.
Thanks
Measure between Tp301 & p3023 adjust for about 20 - 25mV.
The driver transistors do dissipate power and get quite warm. I have measured them at 80°C and that is normal.
The driver transistors do dissipate power and get quite warm. I have measured them at 80°C and that is normal.
hi
you said measure between Tp301 & p3023, p3023 ( I think you meant Tp302). The voltage between TP301 and TP302 is measured 492mV, with SVR302 all the way down(minimum) and I cannot go below 492mV. The voltage across the output terminals was approx 40mV. If I am not mistaken, TP301 is at the emitter of Q313 and TP302 is at the emitter of Q314. 492mV is way out of 20 - 25mV. The driver transistors (mounted on the heatsink) are not getting hot but Q304 to Q307 are getting very hot and they do not have heatsinks. What could be the problem.
Thanks
you said measure between Tp301 & p3023, p3023 ( I think you meant Tp302). The voltage between TP301 and TP302 is measured 492mV, with SVR302 all the way down(minimum) and I cannot go below 492mV. The voltage across the output terminals was approx 40mV. If I am not mistaken, TP301 is at the emitter of Q313 and TP302 is at the emitter of Q314. 492mV is way out of 20 - 25mV. The driver transistors (mounted on the heatsink) are not getting hot but Q304 to Q307 are getting very hot and they do not have heatsinks. What could be the problem.
Thanks