Class AB automotive dc12-18 hifi level Four Channel Power Amplifier

Thanks. I submitted my design via easyeda + jlcpcb for fabrication and I’m using their assembly service. Total cost was around $25 for 10 boards fully assembled, all through-hole parts. Would have been less if I’d opted for surface mount parts. 2-3week shipping to USA was another $9. Very happy with the cost coming to less than $4/ea.
 

ljm_ljm

Member
2006-09-26 6:47 am
Thanks. I submitted my design via easyeda + jlcpcb for fabrication and I’m using their assembly service. Total cost was around $25 for 10 boards fully assembled, all through-hole parts. Would have been less if I’d opted for surface mount parts. 2-3week shipping to USA was another $9. Very happy with the cost coming to less than $4/ea.
very nice. If you need anything, please contact me.
Tda7850 genuine. About 25 RMB, about 3 dollars.
 
very nice. If you need anything, please contact me.
Tda7850 genuine. About 25 RMB, about 3 dollars.
At last the mask comes off.

As suspected from the very beginning ( from answer #2 on), this exaggerated praise of an old indistinct run of the mill car chipamp WAS a thinly disguised vendor post.
Which should be in the Commercial Forum area.

a dealer who aspires to stand out from the rest, shouldn't we expect a bit more from you than the average ebay or aliexpress vendor
 
I am making an amplifier with 6 pieces, so they will share a large heatsink that’s part of the chassis. I have a number of them from old experiments with led that will be suitable. I am keeping a spreadsheet with costs of the various parts, it will be useful to see when it’s done the total cost.

I have to draw a small pcb for the exterior Phoenix connectors to the 2pin/3pin headers. For the in/outs.

Another pcb to distribute the power from an smps.
Overall I think I can keep costs below $200 for this amp.
 

ljm_ljm

Member
2006-09-26 6:47 am
At last the mask comes off.

As suspected from the very beginning ( from answer #2 on), this exaggerated praise of an old indistinct run of the mill car chipamp WAS a thinly disguised vendor post.
Which should be in the Commercial Forum area.
You think it's complicated. Actually, I only have two chips in my hand.
I don't make money on this chip. The purchase price is 25RMB.
Let me add. I have nearly $1million in American stocks. DIY is amateur. Entertainment.
If anyone is interested. I can help them buy. You can even help them process PCB.
It's very convenient in China. And cheap.
I don't sell tda7850. If you want to ask me what diy kit I'm selling.
I guess the most is the complete set of triode type. I don't sell much integrated circuits.
But I recommend him. Because tpa3116 or tda8920 tda8950 is really bad.

:coffee:
 

ljm_ljm

Member
2006-09-26 6:47 am
I am making an amplifier with 6 pieces, so they will share a large heatsink that’s part of the chassis. I have a number of them from old experiments with led that will be suitable. I am keeping a spreadsheet with costs of the various parts, it will be useful to see when it’s done the total cost.

I have to draw a small pcb for the exterior Phoenix connectors to the 2pin/3pin headers. For the in/outs.

Another pcb to distribute the power from an smps.
Overall I think I can keep costs below $200 for this amp.
Hope to see your products.
In addition, I hope to try to see those with personality. Artwork. Instead of the industrial products such as class D mobile speakers.
 

ljm_ljm

Member
2006-09-26 6:47 am
Wow!!!
NOW I´m humbled!!!!! :eek: :eek: :eek:
Ha, don't think too much. I know Chinese people. Most of them are more than 20 times mine.
The house I live in now can sell for almost $1.5 million. And I have more than one house.
So DIY is a hobby.
Because many of us don't need work to make money.
If you were in China, you would know. I give many people DIY matching products.
of course. If I can design some products. Then sell it. Finally, I can make some money.
I'll be happy, too. This proves that my technology is very powerful. It's more exciting than stocks.
 

ljm_ljm

Member
2006-09-26 6:47 am
So you have no measurements of your own, especially at 12V as your title suggested.


Cheers,
Patrick
This is not the best performance indicator. But it is true.
I don't like good-looking data. I only like real data. Even if it's not that beautiful
It doesn't matter.
 

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