Hi! 
I decided to "build" an amp and I chose a TA2021b kit.
It "just" needs to be soldered.
Also I have no speakers so I am building a pair of those also.
I think an amp kit is the only way to go for me because I know nothing of electronics.
But I want to know more. So this will hopefully be a good start as the kit is inexpensive and if I don't get it to work it won't matter all that much.
My plan is to solder it without knowing what it does and use a battery from my tractor to jumpstart it. Max DC voltage is 14.6.
I don't know if I am expecting too much from myself but I want to focus on a power supply.
I want to really build one and not just solder something. And if it's snowing and I'm outside plowing I won't be listening to music anyway.
So there is no rush. I got power already.
But this isn't about a power supply.
And it's not just about soldering the amp kit. By the way, I will practice soldering on another kit before I solder the amp.
I got the kit with a circuit diagram, partslist, a board layout and a building guidance.
Thanks to a not so good guidance I, as a beginner, have to understand some stuff.
On the circuit diagram near area 1 there is a resistor Ra, a thing Cj and a trimpot(I learned) Rj.
They are painted in grey on the circuit diagram and when I asked why I got back that I don't have to mind that, with an explanation that they will adjust the output DC offset. They are optional.
If I don't use them there will be an output DC offset at max +-150mV.
If I use them them there will be an output DC offset at max +-1mV.
Why is it +-1mV? When I use +-3 I mean that the value is somewhere from -3 to +3. It is not that exact.
So I did some more reading and 150mV DC Bias seems high and maybe will affect the sound quality and maybe even damage stuff on the board. It probably won't damage anything because you can't sell a kit that will damage things. But signal quality is important.
I will use a battery at first and maybe there will not be any AC imbalance? The DC bias is all about AC to DC? Or is it the analog audio signal that will be imbalanced whatever the power supply? They are waves both of them right?
The circuit diagram shows +6V at the output. I am far from being able to measure it. Maybe it will just explode or burn up when I turn it on. Will there be 6V when the amp is turned on without any input signal? Is 6V the goal for this design at idle?
I guess that the trimpots will be used for coming close to 6V.
Should I measure all the points marked on the circuit diagram at idle?
I registered to ask you this and I apologize my ignorance.
Actually I am hesitating to post this. I know how simple this must be for you.
If you answer me, please be very simple or I won't understand.
Best regards
I decided to "build" an amp and I chose a TA2021b kit.
It "just" needs to be soldered.
Also I have no speakers so I am building a pair of those also.
I think an amp kit is the only way to go for me because I know nothing of electronics.
But I want to know more. So this will hopefully be a good start as the kit is inexpensive and if I don't get it to work it won't matter all that much.
My plan is to solder it without knowing what it does and use a battery from my tractor to jumpstart it. Max DC voltage is 14.6.
I don't know if I am expecting too much from myself but I want to focus on a power supply.
I want to really build one and not just solder something. And if it's snowing and I'm outside plowing I won't be listening to music anyway.
So there is no rush. I got power already.
But this isn't about a power supply.
And it's not just about soldering the amp kit. By the way, I will practice soldering on another kit before I solder the amp.
I got the kit with a circuit diagram, partslist, a board layout and a building guidance.
Thanks to a not so good guidance I, as a beginner, have to understand some stuff.
On the circuit diagram near area 1 there is a resistor Ra, a thing
Cj and a trimpot(I learned) Rj.They are painted in grey on the circuit diagram and when I asked why I got back that I don't have to mind that, with an explanation that they will adjust the output DC offset. They are optional.
If I don't use them there will be an output DC offset at max +-150mV.
If I use them them there will be an output DC offset at max +-1mV.
Why is it +-1mV? When I use +-3 I mean that the value is somewhere from -3 to +3. It is not that exact.
So I did some more reading and 150mV DC Bias seems high and maybe will affect the sound quality and maybe even damage stuff on the board. It probably won't damage anything because you can't sell a kit that will damage things. But signal quality is important.
I will use a battery at first and maybe there will not be any AC imbalance? The DC bias is all about AC to DC? Or is it the analog audio signal that will be imbalanced whatever the power supply? They are waves both of them right?
The circuit diagram shows +6V at the output. I am far from being able to measure it. Maybe it will just explode or burn up when I turn it on. Will there be 6V when the amp is turned on without any input signal? Is 6V the goal for this design at idle?
I guess that the trimpots will be used for coming close to 6V.
Should I measure all the points marked on the circuit diagram at idle?
I registered to ask you this and I apologize my ignorance.
Actually I am hesitating to post this. I know how simple this must be for you.
If you answer me, please be very simple or I won't understand.
Best regards