Cap is in sound health. 🙂
Ouch! Should I increase the Wattage of the Resistor to 1 Watt?
PCB Layout shows 10 Ohm 0.5 watt.
But I saw 4.7 Ohm 1 watt is used in the Parts List.
Which value should I use ?
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post216 is wrong.
The shunt resistors should be labeled Series resistors.
The middle set of smoothing capacitors are on the wrong side of the series resistors.
The amplifier draws it's current to meet the speaker demand from the LAST set of capacitors.
The previous set or sets of capacitors are simply there to charge up the last set if they become depleted.
The shunt resistors should be labeled Series resistors.
The middle set of smoothing capacitors are on the wrong side of the series resistors.
The amplifier draws it's current to meet the speaker demand from the LAST set of capacitors.
The previous set or sets of capacitors are simply there to charge up the last set if they become depleted.
Burnt, or hot, or warm Zobel resistors tell you the amplifier is oscillating.
Stop and find the oscillation, otherwise you will blow up the amplifier.
Stop and find the oscillation, otherwise you will blow up the amplifier.
Thank you sir.
Can the oscillation be in the tone control section ?
Just found a bad solder joint damaged the BC558 in the PSU of the preamp. And the voltage was like +15.67 and -32.25. I replaced the faulty one with BC560c and now the voltage is back to normal.
Zobel Resistor is cool now.
Burning started after I added the Project 88 preamp of Rod Elliot after the ML3 tone control section. The output from the preamp is being fed to LM3886 now.
Or perhaps with ML3 I don't need the Project 88 preamp? Any thought?
Thank you again sir for the valuable info.
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Is your amplifier DC coupled?
AC coupled amplifiers do not allow DC to upset the amplifier operation and help prevent damage to the speakers.
AC coupled amplifiers do not allow DC to upset the amplifier operation and help prevent damage to the speakers.
I guess it is AC coupled.
I am using Sir Mile's LM3886 circuit.
Project 88 preamp has a 2uFd cap at the output.
Same for the ML3. It has a 10uFd Electrolytic cap at the output.
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It's AC coupled obviously.
I checked posts you mentioned and then double checked the amps. I missed nothing.
Everything is there as per the circuit.
I checked posts you mentioned and then double checked the amps. I missed nothing.
Everything is there as per the circuit.
OK. I share the eagle's PCB.
I tested this amplifier. There is no thumb on power on and sounded nice.
I tested this amplifier. There is no thumb on power on and sounded nice.
I bought it from Calcutta. The price of the TF plastic package is 250 INR per piece now. Metal version is cheaper. But with a little bargaining or checking out other shops, I guess you can get it for even cheaper price.
I guess it is available in Delhi too.
You can try at Vimla Chawk (at Chandni Chawk ) in Calcutta.
There is a row of shops at the Vimla Chawk Building.
Price is usually cheaper there.
First have a look there and compare the prices.
Here is a list, you might try this:
1. Everest Electronics Corporation ( Vimla Chawk, 1st floor )
2. Nahar Electronics ( Vimla Chawk, 2nd floor I guess)
3. Rana Electronics ( Chandni Chawk, adjacent place )
4. NG Electronics ( Chandni Chawk) ( Good audio related components, heat sink, PCB, complete audio kits, cabinets etc. Sometimes a little high price but good stock)
5. Railton ( wide range of products but the price is very high, my personal experience, may be different with others)
6. Gemini ( chandni chawk)
Hope this helps.
Err, are you sure you are "reluctant" ? 🙂
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dear sir,
you are a quick reply man .thank you sir .my question was for in delhi because that place is near my town place about 400km.thanks again sir
I hope someone from or near Delhi can help you locate a shop.
I understand the problem. LM3886 is hard to find everywhere in India. I had to wait some one year to get the chip. But now I feel it's worth the wait. Great chip with great sound using the design of Mr Mile.
Did you try online shops in India?
