Dear Mr. Mile,
here is my eagle version of your PSU+Protect+Clip PCB. I found a few discrepancies in the schematic, but I laid the PCB as per your PCB layout. pl inform if there are any errors.
regards
prasi
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Mr.mile any comments on the layout of PSU? I am getting the psu circuit screen printed to try on for the kelvin amp stereo.
Reg prasi
Yes. I redrew your PCB. I am yet to reach a level where I can prepare my own layouts based on your schematic. . thanks for the confirmation. One other help. I did not like the sound of lm3886. My cheap commercial solid state amp makes much better sound. I have posted this query in lm3886 thread. Tell me whether kelvin amp can be used as a full range amp and can it produce audiophile quality sound? I am interested to know the specs of kelvin amp.if you have. Like thd. Imd . bandwidth etc.
Sorry for mistakes as I am typing from mobile.
Reg
Prasi
Hi,
I have assembled the F120. The first test shows a lot of trouble
Quiescent current is 160mA but the output has oscillations at about 20 kHz and + -40Vpp. Supply voltage is + - 52V DC. Zobel (4R7 + 100n) is really warm and R18 (22R) is very hot. A signal at the input (0.5V 1kHz sine) can not be seen at the output.
So tomorrow I will go and check everything again and make some measurements.
regards Olaf
I have assembled the F120. The first test shows a lot of trouble
Quiescent current is 160mA but the output has oscillations at about 20 kHz and + -40Vpp. Supply voltage is + - 52V DC. Zobel (4R7 + 100n) is really warm and R18 (22R) is very hot. A signal at the input (0.5V 1kHz sine) can not be seen at the output.
So tomorrow I will go and check everything again and make some measurements.
regards Olaf
Attachments
Hi,
I have assembled the F120. The first test shows a lot of trouble
Quiescent current is 160mA but the output has oscillations at about 20 kHz and + -40Vpp. Supply voltage is + - 52V DC. Zobel (4R7 + 100n) is really warm and R18 (22R) is very hot. A signal at the input (0.5V 1kHz sine) can not be seen at the output.
So tomorrow I will go and check everything again and make some measurements.
regards Olaf
Input gnd and power gnd is not separate on your pcb...
Hi Mile,
yes, unfortunately you're right 🙂. I will correct that. Probably is this not the only error...
Then I'll try again.
Thanks and Greetings
Olaf
yes, unfortunately you're right 🙂. I will correct that. Probably is this not the only error...
Then I'll try again.
Thanks and Greetings
Olaf
Hi,
😀😀😀 now the amp is singing 😀😀😀
I corrected the input GND and changed all components in the oscillating negative supply and the opamp.
The sound is very strong and clear, but I tested only on old speakers.
It runs on + -52V, all is cool, quiescent current is only 8mA (?), offset is 1 mV.
Unfortunately my oscilloscope is broken, so I have no other pictures.
I will build the second channel with the corrected layout as soon as I find time 🙂
regards Olaf
😀😀😀 now the amp is singing 😀😀😀
I corrected the input GND and changed all components in the oscillating negative supply and the opamp.
The sound is very strong and clear, but I tested only on old speakers.
It runs on + -52V, all is cool, quiescent current is only 8mA (?), offset is 1 mV.
Unfortunately my oscilloscope is broken, so I have no other pictures.
I will build the second channel with the corrected layout as soon as I find time 🙂
regards Olaf
Attachments
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