sir here is the pic. of my ongoing project...
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SIR, offset out 0.0 i try also valve light, the light is dim sir..but 10r/2w resistor next to coil is hot very hot..sir..😕
MEASURE THESE VOLTAGES.
Change fuses with resistors.
Measure resistors voltage ,without any input signal not speaker on output.
It seems like oscillations.
Did you have an oscilloscope?
Offset is d.c voltage
Oscillation is a.c voltage
Measure on a.c range.
Change fuses with resistors.
Measure resistors voltage ,without any input signal not speaker on output.
It seems like oscillations.
Did you have an oscilloscope?
Offset is d.c voltage
Oscillation is a.c voltage
Measure on a.c range.
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Last edited:
sir, here some pic of my project...thank you so much for your help sir, i give you an update thank sir and more power...
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SIR, offset out 0.0 i try also valve light, the light is dim sir..but 10r/2w resistor next to coil is hot very hot..sir..😕
On this pcb C2 100pF missing
thank you so much sir apex and sir thimios for your help...i find out the missing cap. 100pf in the diagram...thanks so much ...i try to fix it...god bless and more power....
Sir Miles, sir Alex and sir Thimios thanks you so much you all ..now my amp.start shaking ng room thank you so from the bottom of my heart....
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Sir mile thank you so much sir, Sir thimios and sir alex thank you so much...god bless you all....🙂
New PCB for Sanken's transistors V3.3
.....another PCB for Sankens , have split Q7 from Q8 ....😉
and I need to check somebody if it's OK , and then I will post layout in black and white and the rest of files .🙂
Regards ,Alex
.....another PCB for Sankens , have split Q7 from Q8 ....😉
and I need to check somebody if it's OK , and then I will post layout in black and white and the rest of files .🙂
Regards ,Alex
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Hi Guys,
I see some of you have working models so this amp must work but I am struggling to get mine going. I'm not getting any signal through to the output. As a matter of fact I have too much interference on the input to even get a clean reading on the scope there. I'm using an NTE 941M for the servo and that may be part of the problem I'm not sure. I tried building a spice model but it is showing as bad of results as I am getting from my amp. I am attaching the spice model and Cordell models. If one of you who knows ltspice could take a look, maybe you can find the issue. I would like to get it working so I can use it to trouble shoot my boards.
I built the amp from the foil pattern in post 1625. There are two 100n caps on the board that are not in the schematic. I added those to the spice model. Any help appreciated.
Blessings, Terry
I see some of you have working models so this amp must work but I am struggling to get mine going. I'm not getting any signal through to the output. As a matter of fact I have too much interference on the input to even get a clean reading on the scope there. I'm using an NTE 941M for the servo and that may be part of the problem I'm not sure. I tried building a spice model but it is showing as bad of results as I am getting from my amp. I am attaching the spice model and Cordell models. If one of you who knows ltspice could take a look, maybe you can find the issue. I would like to get it working so I can use it to trouble shoot my boards.
I built the amp from the foil pattern in post 1625. There are two 100n caps on the board that are not in the schematic. I added those to the spice model. Any help appreciated.
Blessings, Terry
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Hi Terry,
There are two mistakes in your model:
- R19 must be 1meg (not 1m);
- Q10 must be BC560C (not bc550C).
After corrections it runs fine 😉
Cheers,
Valery
Terry, you have to have some special mouse for drilling 🙂 I think, that you spent more time with etching, than is necessary....
Hi Valery,
Thanks, that fixed it.
Hey Maxwell,
I much prefer board house boards but I'm getting a stack of extra boards so I have resolved to etching lately. I etched and filled a pair for this amp and neither are working. Hopefully having a working spice model will elp me get to the bottom of it.
Blessings, Terry
Thanks, that fixed it.
Hey Maxwell,
I much prefer board house boards but I'm getting a stack of extra boards so I have resolved to etching lately. I etched and filled a pair for this amp and neither are working. Hopefully having a working spice model will elp me get to the bottom of it.
Blessings, Terry
These were very poor boards. Radio Shack double sided. The substrate is very brittle and blows out easily. The pitting in the copper is due to poor iron transfer and long etching time to remove the second side. I won't use these again. It's unlikely any of my home etched boards will ever find their way into an amp case. They are strictly for learning.
Blessings, Terry
Blessings, Terry