Hi all,
I'm not at an electronics expert, so this might sound like a dumb question.
I have bough one of this TDA7492P-Bluetooth-Amplifier-Wireless-Receiver and I'm actually quite surprised it works with a decent quality, and I can finally use a pair of old forgotten speakers with it.
However, I have this strange issue: every time I start playing a song, this weird noise that I could only describe as somebody tapping on a mic quickly for one sec happens.
Does anybody know what this is ? Can I do something about it ?
I have checked the other posts about this board but I don't see a similar issue.
Thanks in advance !
I'm not at an electronics expert, so this might sound like a dumb question.
I have bough one of this TDA7492P-Bluetooth-Amplifier-Wireless-Receiver and I'm actually quite surprised it works with a decent quality, and I can finally use a pair of old forgotten speakers with it.
However, I have this strange issue: every time I start playing a song, this weird noise that I could only describe as somebody tapping on a mic quickly for one sec happens.
Does anybody know what this is ? Can I do something about it ?
I have checked the other posts about this board but I don't see a similar issue.
Thanks in advance !
The BT protocol is complex, and includes many parts: frequency hopping at a 1600Hz rate, plus various sync/frame/keep alive info at a lower rate.
All of this heavily modulates the current consumption, but if you have sufficient bypass, the 1600 whine will not break in the audio, but the LF heartbeat still will.
A floating supply or an isolation transformer on the audio are the only 100% effective solution.
All of this heavily modulates the current consumption, but if you have sufficient bypass, the 1600 whine will not break in the audio, but the LF heartbeat still will.
A floating supply or an isolation transformer on the audio are the only 100% effective solution.
Thanks for your answer Elvee.
I don't understand 100% of what you've written since I lack the technical skills, but do you mean that this issues are related to the power supply that I'm using ?
I don't understand 100% of what you've written since I lack the technical skills, but do you mean that this issues are related to the power supply that I'm using ?
Yes, the PSU needs to be well bypassed, but more importantly it has to be well separated from the audio section. Ground loops in particular must be avoided, but since it is a complete module, it is beyond your reach.
In the description, I see that LEDs flash for 3s at startup: maybe it's related to the tapping noise?
Your source could also be affected by the RF emission. Try different sources and configurations
In the description, I see that LEDs flash for 3s at startup: maybe it's related to the tapping noise?
Your source could also be affected by the RF emission. Try different sources and configurations