Hi, i have a problem to disable this bluetooth thing... but i don't find any kind of solution for this...
I have try to disable the BT antenna and nothing happens.... this problem is sh**** because my neighbor is always connecting to it. And i can't hear anything from my PC (Connected via AUX)
Board is a ZK-TB21 (2.1 Channel Power Amp)
Chip is a JL AS208P08912-25A4
I have try to disable the BT antenna and nothing happens.... this problem is sh**** because my neighbor is always connecting to it. And i can't hear anything from my PC (Connected via AUX)
Board is a ZK-TB21 (2.1 Channel Power Amp)
Chip is a JL AS208P08912-25A4
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Can you shield the BT antenna with foil, to reduce it's range to less than that which your neighbour can reach?
I truncated the pins directly on the BT chip, first the fourth (by mistake) then the fifth and that reduced the range of the BT to one metre.
The problem was old but in the last few days it was too persistent, I thought they were attempts by the neighbors and I intervened by solving the BT but the defect persists: it wasn't access attempts by the neighbors but a power problem. I have a series of "bumps", the power led cycles the bumps then everything goes back to normal. Every half hour or so but it's completely random, I'm investigating, I don't think it's the power supply but rather the boot logic of the TB21.
The problem was old but in the last few days it was too persistent, I thought they were attempts by the neighbors and I intervened by solving the BT but the defect persists: it wasn't access attempts by the neighbors but a power problem. I have a series of "bumps", the power led cycles the bumps then everything goes back to normal. Every half hour or so but it's completely random, I'm investigating, I don't think it's the power supply but rather the boot logic of the TB21.
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SOLVED: Fine tip soldering iron, lots of patience, three small copper wires. Remove the bluetooth chip, connect the dots shown in the picture with wires and bluetooth will no longer be a problem.
I cut the pins of the chip with the cutter and then I removed the pieces left on the pcb with the tip of the soldering iron
No more bumps, the problem was the bluetooth chip that made the nearby voltage reducer (M5350B) overheat, now everything works fine.
I cut the pins of the chip with the cutter and then I removed the pieces left on the pcb with the tip of the soldering iron
No more bumps, the problem was the bluetooth chip that made the nearby voltage reducer (M5350B) overheat, now everything works fine.
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hi giovanve,
i have this zk-tb21, and it starts doing something wierd. this amplifier sometimes can not be turned on. even sometime when it is working, suddenly it shuts down and restarts. do you think it is the bluetooth chip problem? thanks.
i have this zk-tb21, and it starts doing something wierd. this amplifier sometimes can not be turned on. even sometime when it is working, suddenly it shuts down and restarts. do you think it is the bluetooth chip problem? thanks.
i don't have the tpa version. only chipstar. it sounds good. my speakers and sub were edifier's. it replaced the edifier amp. sounds better than the original edifier amp on the same speakers.
Mine works with exactly 24volt 3 ampere and it does not get hot.
The zk-mt21 I have works with 22.5volt 2.5ampere and gets hotter but works easily without active cooling.
Both amps are dead quiet and sound really good. Have impact on the sub.
https://www.diyaudio.com/community/...ription-subwoofer-gallery.207217/post-7494416
The zk-mt21 I have works with 22.5volt 2.5ampere and gets hotter but works easily without active cooling.
Both amps are dead quiet and sound really good. Have impact on the sub.
https://www.diyaudio.com/community/...ription-subwoofer-gallery.207217/post-7494416
in my tb21, i notice the difference between aux and bluetooth. testing with the youtube left right speaker test, the bluetooth channel gives stereo left right. however the aux channel does not. do you guys also experience that? i am thinking of removing the bluetooth chip as well because it is hot.
using This Tutorial
its for YS-TB21 (variant of TB-21), but theoritical is same.. just follow line for TB-21..
im succesfully follow this tutorial for my YS-TB21 because Bluetooth Chip broken.. but compensation USB not work again..
Bluetooth Chip control anything (BT,USB, Line-In & supply for Op-Amp)
its for YS-TB21 (variant of TB-21), but theoritical is same.. just follow line for TB-21..
im succesfully follow this tutorial for my YS-TB21 because Bluetooth Chip broken.. but compensation USB not work again..
Bluetooth Chip control anything (BT,USB, Line-In & supply for Op-Amp)
I did this mod but unfortunately I have no sound out, the blue LED lights up but not even a hiss, any idea why?
i also did the mod. led lights up but no sound. i guess the chipstar ic is still muted. any guess and idea how to solve?