Triggering VCR Button Presses with PNP transistors

Using Arduino General Electronics
#1

Hello there,

I was trying to figure out if VCR buttons can be triggered with PNP transistors?

I soldered wires to the non-negative sides of 10 buttons on the VCR which when pressed, create pathways to ground.

With the 10 wires on the positive sides of each button, would I be able to connect each button to ground with a PNP or NPN?

I figure with a PNP, if the base goes low, it could connect collector with the emitter, but also thought maybe applying voltage to the base of NPN's it could connect the collector to ground as well.

It seems a little tricky but I have both Tip31c and Tip32c transistors. I'm having trouble understanding how to simulate a button press with a transistor.

Thanks for your help.

#2

I was trying to figure out if VCR buttons can be triggered with PNP transistors?

It all depends on the circuit of the VCR, there are many ways the designer could do it and each one needs a different solution.

The simplest way is to use a small relay, with the contacts wired across the button's contacts.

To use a transistor you need to measure the voltages on the VCR button, and see what happens on press and release. Then use an opto isolator to connect this to the Arduino, emitter to lowest voltage and collector to highest. Note this is for an NPN transistor, that way you have no need for a common ground.

#3