It shouldn't be shrieking. It should play normally up to a reasonable level.
Does the bulb light up when it shrieks?
Do you see excessive noise on the rails?
Do you see a strange signal on the input of one inductors while the other is a clean square wave?
I forgot a previous question. On the oscilloscopes page, start reading at 'Scope Display Markings:' and read the next few sections. There are likely many sites online if you still don't quite understand. Basically, you use the scope display to determine the time for a complete cycle and use the formula F=1/time.
Does the bulb light up when it shrieks?
Do you see excessive noise on the rails?
Do you see a strange signal on the input of one inductors while the other is a clean square wave?
I forgot a previous question. On the oscilloscopes page, start reading at 'Scope Display Markings:' and read the next few sections. There are likely many sites online if you still don't quite understand. Basically, you use the scope display to determine the time for a complete cycle and use the formula F=1/time.
Ok Perry the bulb has not lit up yet.
I don't see any excessive noise on the rails.
And the inductors there's a clean sqaurewave on one side and the other side the signal im not sure about pic below to help both inductors are identical.
SCOPE SETTINGS FOR PICS 50mv / 10us x10
I don't see any excessive noise on the rails.
And the inductors there's a clean sqaurewave on one side and the other side the signal im not sure about pic below to help both inductors are identical.
SCOPE SETTINGS FOR PICS 50mv / 10us x10
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Oh perry i forgot to mention that the screeching and that signal in the pic above are in sync with each if it screeches the signal move in sync with it
I don't think you can hear anything with that high of a frequency. Put the scope on about 1ms to see if anything shows up.
Here's a pic below of scope setting 50mv / 1ms x10
If i touch on the driver board around r4 & r5 it makes the screeching turn into a squealing/ static
If i touch on the driver board around r4 & r5 it makes the screeching turn into a squealing/ static
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Do you have a capacitor that you could parallel with the speaker to see if that stops the noise?
Anything suitable for an output filter capacitor. Mylar of 10uF is very good. Two polarized caps in series but with a reverse connection is also OK. 22uF or larger (I've used up to two 220uF).
Ok so when you say two polarized caps in series but with a reverse connection are you meaning to put the two caps in series and put in reverse on the speaker terminal?
Does voltage rating matter on the caps
Does voltage rating matter on the caps
The negatives are generally connected together when they are connected in series. This is a fairly common practice in amps that need any significant filter capacitance at high voltage.
Voltage isn't an issue when working with the low rail voltage.
Attached shows one example.
Voltage isn't an issue when working with the low rail voltage.
Attached shows one example.
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So hook them up positive to positive instead of negative to negative?
Messing with the amp more I've found that the c6 cap on the driver board is connected to r4/r5 and when pushed on it's causes a lot of noise as well as the LPF potentiometer wiggling the potentiometers when you cut your finger on the LPF it makes the amp Buzz
Messing with the amp more I've found that the c6 cap on the driver board is connected to r4/r5 and when pushed on it's causes a lot of noise as well as the LPF potentiometer wiggling the potentiometers when you cut your finger on the LPF it makes the amp Buzz
Sorry don't mean to ask so many questions but in the diagram you sent there in series with the negative sides together should I do it like in the diagram or in reverse
When you said a reverse connection is ok also it threw me off a little sry
When you said a reverse connection is ok also it threw me off a little sry
Ok so just hook it across the + and - speaker terminals with sub still hooked up as well just wanna make sure I'm getting right
It still screeching it sounds like old dial up internet is the best way I can describe it but the audio sounds clean and strong other wise
LPF potentiometer if you touch it in anyway it's buzzes crazy no other potentiometers does it though
LPF potentiometer if you touch it in anyway it's buzzes crazy no other potentiometers does it though
It almost like a ground issue or something feedback of some sort because if a hold the power supply wires to amp in my hand and move em around ita goes away then back
It's possible that you have other issues. Are the RCA shield grounds intact?
At the output of the op-amp that drives the driver board, do you see the noise?
Did the capacitor reduce the visible noise on the output of the amplifier?
At the output of the op-amp that drives the driver board, do you see the noise?
Did the capacitor reduce the visible noise on the output of the amplifier?