Auto switch to "Line In" source

DIY Products&Projects DIY Product Questions
1

Hi all,

I am planning to create a setup in which a up2stream Pro V3 would be connected to an external amplifier going in to a 2 spreaker setup.

I would want to use 2 input methods.
-Line in, connected to my projector for my home theatre system
-Spotify connect for listening to music though the same speakers when not using the projector

I have figured out (using the up2stream Amp I use for another audio system) that while a Line In is connected, it is possible to automatically switch to Wifi (spotify connect).
However, whenever I disconnect the Wifi source and want to start the Line In, I have to select the source from the app.

Is there a way to switch to ā€œLine Inā€ mode automatically? It seems like a hassle to open the app every time I start the projector.

Thanks in advance,
Rik

2

Maybe a current sense switch on the projectors power supply? A DPDT relay could then choose the input source.

3

Hi @Steve1
Thanks for your response.
That seems like it would work. Do you have any more information about what to do with the DPDT relay. Is there a pin on the up2stream Pro I can connect to to change the input source?

4

Hi
If you are techy enough, you can trick the board, as when you insert a jack to the line input it automatically enables the Line In mode. In the jack socket on the board you will find 2 contacts that detect whether a jack is connected or not. You can use this. I do not recall if the contact is closed when no jack is inserted or open. For construction simplicity reasons, I believe it is opened by the insertion. Just test this with a voltmeter and then ā€˜foolā€™ the system either with a relay or a photocoupler depending on your set up. You probably will have to neutralize the ā€˜hardā€™ switch contact on the plug.
Cheers,
N.

5

@Nobu, thatā€™s very helpful information and Iā€™ll keep that one for future/further investigation.

@RikVB, I donā€™t think the extension port Key pin will be of any help as using the Mode switch would scroll thru BT, WIFI, USB, AUX.
If you donā€™t feel confident doing as Nobu suggests, which is probably the best way by the way, I can provide an alternate sketch.

6

Hi Rik,
Current firmware does not support this feature, weā€™ll consider to update firmware to support.

1 Like
7

Hello @RikVB ,
Iā€™m not sure if this works for the Pro V3 (I have an A50+), but you can try the UART commands (via TCP passthrough) available on this page: API Files for Developers
MCU+PAS+RAKOIT:ASW:1& to enable automatically switching back to previous source,
MCU+PAS+RAKOIT:POM:LINE-IN& to set power on mode to line-in.

1 Like
8

This should be a solution, I nearly forgot this featureā€¦