@jerrylong - It's against the forum rules to start multiple threads for the same project. Therefore, all your threads pertaining to the M10 project have been merged together as a result.
Why would you expect the same result?! Please compare the two circuits you posted above, do you not see the differences in the grid voltages? Another case of garbage in garbage out...
what fool I am, I thought the DC of grid will not affect the tube
after add a 130V DC to the grid, it is same as the real circuit. Thank you very much😀
the building up will be finished soon
There ia one more Power Tran needed, after finished it I will use OSC to see the real output wave to compare with simulation.
There ia one more Power Tran needed, after finished it I will use OSC to see the real output wave to compare with simulation.
Output wave clearly shows clipping.
Did you simulate the voltage gain of this stage? It will be more than 50. 😱
Do you expect this to be a normal line stage? 😕
In the complete M10 preamp it is attached to a low gain phono stage (gain approx. 40, delivering some 200 mV into your line stage with a standard 5 mV input); that's why you need the "excessive" gain of your stage.
But this has been mentioned before, remember? 🙄
5687 operating point is poorly chosen; try 7k5 of cathode resistance.
I used the buying OPT for the test, the turn ratio is 33:1, I will test it in real circuit to see if it has the same problems as simulation. I have not finished DIY OPT yet
Tonight I tested the Voltage of each stage, line stage, #2 and #3 stage of phono are fine. There is problem of #1 of phono. Green one is LEFT and Red one is Right, I think something wrong with LEFT, can anyone help me to find it?
I have switched 6072 of left and right, the problem remains on left, so it is not tubes problem
I pull out the 6072 and test the res of each section
1,I have tested the res from B+ to 6072 socket #1 L and R is the same, about 120K
2,socket #3 to #6 L and R is the same,about 2K
3, socket #8 to GND L and R is the same,about 5K
what I missed to lead the problem of LEFT?
1,I have tested the res from B+ to 6072 socket #1 L and R is the same, about 120K
2,socket #3 to #6 L and R is the same,about 2K
3, socket #8 to GND L and R is the same,about 5K
what I missed to lead the problem of LEFT?
I haves the problem
This is the right circuit
After I short C1, the result is same as the problem
I take down this cap from LEFT
And changed a new on
Problem solved
Then I tested the cap, it soft breakdown, so it hard to find out this problem when power off
This is the right circuit
After I short C1, the result is same as the problem
I take down this cap from LEFT
And changed a new on
Problem solved
Then I tested the cap, it soft breakdown, so it hard to find out this problem when power off
My friend has made a 6.5K:600 OPT, it is finished today. I put them on, it is quite good, till now the clone job of M10 is finished, it sound very good.
then I will use LT-SPICE to test it and compare with the real circuit. If there is any thing to improve I will go on.
then I will use LT-SPICE to test it and compare with the real circuit. If there is any thing to improve I will go on.
@Jerry: could you please show me the link of shop from China where I can buy that OPT (33:1 or 5:1)? I can purchase these from taobao
Many thanks,