probelm located
well i suspected just as you did with T10-13. So i removed transistors T6 and T7 to make sure they werent interfering, but when it came to removing the base pin for the main transistors T10-13 it was lose... must have rattled lose, so soldered it back on and now its all fine. So now it all works good, im glad it was just something simple and not faulty transistors.
well i am a 3rd year electrical engineering student(so u know my level approx), now im curious how would you have said to test the transistors? last time i tested them with a CRO, voltage source and signal generator.
well i suspected just as you did with T10-13. So i removed transistors T6 and T7 to make sure they werent interfering, but when it came to removing the base pin for the main transistors T10-13 it was lose... must have rattled lose, so soldered it back on and now its all fine. So now it all works good, im glad it was just something simple and not faulty transistors.
well i am a 3rd year electrical engineering student(so u know my level approx), now im curious how would you have said to test the transistors? last time i tested them with a CRO, voltage source and signal generator.
Well I have a Good Sanwa Transistor Tester, But Thats Me.
What I would have suggested was a Small flashlight bulb in the collector and to the positive of a battery.
Emitter to the Negative of the battery.
And a 25K or 100K pot in series with a 1K resistor going from the positive of the battery to the Base of the transistor.
(Value of Pot depends on Gain of transistor and 1k for maximum Current Limit)
But Adjusting the Base Bias should allow for good control of the brightness of the Light bulb.
Simple, But works.
What I would have suggested was a Small flashlight bulb in the collector and to the positive of a battery.
Emitter to the Negative of the battery.
And a 25K or 100K pot in series with a 1K resistor going from the positive of the battery to the Base of the transistor.
(Value of Pot depends on Gain of transistor and 1k for maximum Current Limit)
But Adjusting the Base Bias should allow for good control of the brightness of the Light bulb.
Simple, But works.
.
hi
i make tis amplifier for my final project in the last year.
and i dont understand the working of it entirely.
Can someone give me a short working of the amplifier,please?
hi
i make tis amplifier for my final project in the last year.
and i dont understand the working of it entirely.
Can someone give me a short working of the amplifier,please?
Read this book:
Right click: save as. It is 5 megs..
It will tell ALL!! 😀
🙂cop:link to pirated copyrighted material removed by moderators)
Right click: save as. It is 5 megs..
It will tell ALL!! 😀
🙂cop:link to pirated copyrighted material removed by moderators)
Hi thunderstruck,
You didn't cover that material in your course?
To be honest with you, using the forums for a school project defeats the purpose of having you research and learn in the process. For that reason, we don't allow it.
In real life you will need to know how to go out and do research. Forums like these are not always accurate. We all post on our experiences and how each of us understands a subject. You need to find the cold, hard, true facts.
Lastly ...
ostripper, I know you are trying to help. However, we do not allow copyrighted material to be posted directly or via a link. If a book is that good, the author deserves his royalties. You should see my library of books. It takes time to amass them. A library is a good place to borrow a book.
For me, I retain knowledge much better if I can hold a book and read it. Computer screens are not my thing at all.
-Chris
You didn't cover that material in your course?
To be honest with you, using the forums for a school project defeats the purpose of having you research and learn in the process. For that reason, we don't allow it.
In real life you will need to know how to go out and do research. Forums like these are not always accurate. We all post on our experiences and how each of us understands a subject. You need to find the cold, hard, true facts.
Lastly ...
ostripper, I know you are trying to help. However, we do not allow copyrighted material to be posted directly or via a link. If a book is that good, the author deserves his royalties. You should see my library of books. It takes time to amass them. A library is a good place to borrow a book.
For me, I retain knowledge much better if I can hold a book and read it. Computer screens are not my thing at all.
-Chris
people don't like books anymore and love the internet instead.
Strangely this internet provides good access to used books. Recently I even ordered a used book in the US and let it shipped to Germany!
It wasn't cheap, but it was worth the price! 🙂
regards
Strangely this internet provides good access to used books. Recently I even ordered a used book in the US and let it shipped to Germany!
It wasn't cheap, but it was worth the price! 🙂
regards
My oldest daughter LOVES books , every time we move I have
to haul her library ...400LBS of books (good for body)😀
She would rather read her real books than read my PDF's
(I have all her books as well).
I also love books but could not afford/
have space for mine in real form (3000+ PDF's=3DVD-r's)
That many would be in tons ,no castles here.
(no library locally).
P.S. No more direct links//understood...😎
to haul her library ...400LBS of books (good for body)😀
She would rather read her real books than read my PDF's
(I have all her books as well).
I also love books but could not afford/
have space for mine in real form (3000+ PDF's=3DVD-r's)
That many would be in tons ,no castles here.
(no library locally).
P.S. No more direct links//understood...😎
I know the working of the schematics.but just not every detail.
We saw a rough working of amplifiers in course.
Just not every detail.
And certainly not class B and class AB together.
Asking some information about the circuit is allowed.
It would be insane to know every detail of the schematic all on our own.🙂
We saw a rough working of amplifiers in course.
Just not every detail.
And certainly not class B and class AB together.
Asking some information about the circuit is allowed.
It would be insane to know every detail of the schematic all on our own.🙂
question DC protection
i have a question about the DC protection
maybe it is a stupid question.
the 12V that is needed for the relais.
do i have to make a 12V DC supply for it.
in the explanation there just say:The +12V supply was made using a simple small pcb transformer.
but then i think just about a transformer.
and you just have 12V AC.
I know this is a very stupid question.
but can someone help me?
i have a question about the DC protection
maybe it is a stupid question.
the 12V that is needed for the relais.
do i have to make a 12V DC supply for it.
in the explanation there just say:The +12V supply was made using a simple small pcb transformer.
but then i think just about a transformer.
and you just have 12V AC.
I know this is a very stupid question.
but can someone help me?
You will need a 10 or 12 Volt transformer, a bridge diode and a filter capacitor to get the DC output.
Or possibly use a 12 volt Adapter (Wall Wart) from Radio Shack or Elsewhere.
Or possibly use a 12 volt Adapter (Wall Wart) from Radio Shack or Elsewhere.
Hi thunderstruck,
You probably have a low voltage supply already, used for "housekeeping" in your amp. You will need power to run the circuit that "tells" the relay to close or open.
If you don't, you could use a resistor to drop the voltage from one supply, or use a regulator to drop the voltage. I don't think you want yet another cord to plug in, so "wall warts" are out.
Can you post your details of the amp? The current draw of the relay will be important also. It is possible you might be better off with a relay rated at another common voltage. They come with coils rated at 5V, 6V, 12V, 24V and 48V most commonly. The nice thing here is that the required current drops as the voltage rating is increased. The same coil power is required.
If this is not easy for you, post the schematic of the protection circuit and amplifier. Then we can give you answers that will apply to what you are doing.
-Chris
You probably have a low voltage supply already, used for "housekeeping" in your amp. You will need power to run the circuit that "tells" the relay to close or open.
If you don't, you could use a resistor to drop the voltage from one supply, or use a regulator to drop the voltage. I don't think you want yet another cord to plug in, so "wall warts" are out.
Can you post your details of the amp? The current draw of the relay will be important also. It is possible you might be better off with a relay rated at another common voltage. They come with coils rated at 5V, 6V, 12V, 24V and 48V most commonly. The nice thing here is that the required current drops as the voltage rating is increased. The same coil power is required.
If this is not easy for you, post the schematic of the protection circuit and amplifier. Then we can give you answers that will apply to what you are doing.
-Chris
http://marcusgun.awardspace.com/m250.html
these are the details about the amp and DC protection.
so that is what I tought ,I have to make a 12V DC supply.
tnx for the answer.🙂
these are the details about the amp and DC protection.
so that is what I tought ,I have to make a 12V DC supply.
tnx for the answer.🙂
NickC said:
I did this with my amp and I also noticed there was a lot less hum with no signal present.
Hello Marcus,
I found it very good M-250 and would like to mount the M-250 you would have the design of printed circuit board of the M-250?
Grateful
Antonio Franca
City of Brasilia Brazil
I found it very good M-250 and would like to mount the M-250 you would have the design of printed circuit board of the M-250?
Grateful
Antonio Franca
City of Brasilia Brazil
Help to build the M250 power amplifier
Please can someone help me with the replacements of this transistors, MJE 340/350 , I wish to build the M250 power amp but can't fine the transistors.....Thanks
Please can someone help me with the replacements of this transistors, MJE 340/350 , I wish to build the M250 power amp but can't fine the transistors.....Thanks
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