quantumtangles
- Dec 19, 2012
- 153
- Joined
- Dec 19, 2012
- Messages
- 153
A portable transistor radio worked really well... before I boxed it and hot glued it.
TDA 7010T FM Radio IC
TBA820M Audio Amplifer IC
Although It still works for nearby stations, there is a pulsing variable in pitch thwacking feedback sound (especially at higher volume levels), and it goes away when I touch the exterior of the rechargeable 9v P5 battery powering the radio.
Tried putting a variety of caps between the battery source and the circuit board, Made no difference. Haphazardly tried resistors and diodes. Nothing. In desperation, made an inductor from a few turns of wire and connected it up, but no dice.
I have done something retarded here but cant figure out what it is.
The only thing that stops the interference noise is hand capacitance... when I touch the exterior of the 9v battery.
I tried replacing the rechargeable 9v battery with a standard P5 but it made no difference. Still a thwacking sound at higher volume unless I touch the casing of the battery.
I am about to learn something here... but only if you can shed light on my wtf moment.
Any ideas at all would be most appreciated (I have run out of ideas...for the moment)
TDA 7010T FM Radio IC
TBA820M Audio Amplifer IC
Although It still works for nearby stations, there is a pulsing variable in pitch thwacking feedback sound (especially at higher volume levels), and it goes away when I touch the exterior of the rechargeable 9v P5 battery powering the radio.
Tried putting a variety of caps between the battery source and the circuit board, Made no difference. Haphazardly tried resistors and diodes. Nothing. In desperation, made an inductor from a few turns of wire and connected it up, but no dice.
I have done something retarded here but cant figure out what it is.
The only thing that stops the interference noise is hand capacitance... when I touch the exterior of the 9v battery.
I tried replacing the rechargeable 9v battery with a standard P5 but it made no difference. Still a thwacking sound at higher volume unless I touch the casing of the battery.
I am about to learn something here... but only if you can shed light on my wtf moment.
Any ideas at all would be most appreciated (I have run out of ideas...for the moment)
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