Re: Speaker Jack

Clark Martin
 

You could use the second audio amp in U1.  The TDA2822 is a dual amplifier.  What you’d need to do is this:

Remove R75
Connect U1-6 to VOL-H.  This will give you an auxiliary sound output that is independent of the volume control.
Connect the + terminal of a 470 µF, 16V electrolytic capacitor to U1-3.
Connect the - terminal of the above cap to your auxiliary out mini jack.

The 470 µF could very likely be much smaller, depending on the input impedance of your Signal Link.
Experiment, it won’t hurt.

You may also want to add a resistor divider between the cap and jack to reduce the signal strength, depending on how much your Signal Link can tolerate.

Considering the problem others are having with the TDA2822 you probably should add a resistor in series with the cap, unless you implement the resistor voltage divider, that will provide the same protection.

Clark Martin
KK6ISP

On Mar 2, 2018, at 10:20 AM, Walter <W9KJO@...> wrote:

On Wed, Feb 28, 2018 at 09:47 am, Richie Chambless wrote:
Yes, the yellow wire is the full signal from the product detector. Check your volume potentiometer to ensure it’s connected to the end (orange should be on middle lug). I would think your external amplifier has a capacitor input on it, so I don’t think another cap is necessary. Check to see if DC is present across the volume pot when the side tone is activated.
Ok The yellow wire does not have enough audio for my Signal Link to work with.  it showed some signals.  I have to reconnect to the 3.5mm Audio Out jack and turn the volume up about half way.  which is too loud for my headphones so I need to install a second 3.5mm for my Head Phones.  

I would be much better if I could find a way to get enough audio separate from the actual audio out to the 3.5mm jack

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