Hi there, I have a project to convert an old boombox into a bluetooth stereo. Initially, I used a bluetooth receiver wired to the existing amp, but the output volume was very very low. I thought I would be able to overcome that by using a Bluetooth amp module with a built in receiver.
The trouble is, I had a very elegant solution to use a switched aux jack to bypass the bluetooth module when a device was plugged in, and I'd like to keep that if possible. But since wiring the new amp outputs to the old amps inputs doesn't work.
Has anyone done this type of thing before that could give me some pointers?
In brief, the aim is to have bluetooth functionality which can be overrriden by inserting an aux cable. I'd also like to keep the FM radio of the original stereo if possible.
The boombox is a Sony CFS-220 and the bluetooth module doesn't have a name, but it's a popular and cheap red board that has a tda7492p bluetooth module on board.
The trouble is, I had a very elegant solution to use a switched aux jack to bypass the bluetooth module when a device was plugged in, and I'd like to keep that if possible. But since wiring the new amp outputs to the old amps inputs doesn't work.
Has anyone done this type of thing before that could give me some pointers?
In brief, the aim is to have bluetooth functionality which can be overrriden by inserting an aux cable. I'd also like to keep the FM radio of the original stereo if possible.
The boombox is a Sony CFS-220 and the bluetooth module doesn't have a name, but it's a popular and cheap red board that has a tda7492p bluetooth module on board.
The inelegant solution is a simple Y cable that routes both the external signal and the bluetooth to the preamp section. Basically the same as just tying the BT input into the aux connectors without disconnecting the aux. If an aux source were connected, both aux and BT would play.
I have some BT modules that are basically wired that way, with a sort of pass thru, and it works just fine.
Nore elegant would be a switch between the two. You'd need a DPDT switch for that. Aux left and right go to ine side of the switch, BT to the other. The output (center poles) go to where aux used to be connect to the peamp/amp.
I have some BT modules that are basically wired that way, with a sort of pass thru, and it works just fine.
Nore elegant would be a switch between the two. You'd need a DPDT switch for that. Aux left and right go to ine side of the switch, BT to the other. The output (center poles) go to where aux used to be connect to the peamp/amp.
I didn't see an external audio input on the boombox. Leave it intact and consider one of these. With a little imagination and a 12 volt LiPo a nice unit could evolve..
https://www.walmart.com/ip/AGPtek-W...-Charger-Support-Hands-Free-Calling/777433972
An Afterthought..
I would almost bet the electronics inside the adaptor that I mention doesn't operate at 12 v.d.c. Perhaps 3.7 or 5 volts. Maybe a connection to the existing power supply/battery and a regulator to the needed voltage to operate the adaptor? Just brainstormin'..
https://www.walmart.com/ip/AGPtek-W...-Charger-Support-Hands-Free-Calling/777433972
An Afterthought..
I would almost bet the electronics inside the adaptor that I mention doesn't operate at 12 v.d.c. Perhaps 3.7 or 5 volts. Maybe a connection to the existing power supply/battery and a regulator to the needed voltage to operate the adaptor? Just brainstormin'..
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