Using 3 Channel Video Switcher Module with Arduino

Hey all I am wondering how to go about switch from camera 1, 2 or 3 using this 3 Channel Video Switcher Module on ebay here.
enter image description here

Since there's only V+, V- and signal for the "switch" it looks to take a PWM but I am not quite sure if that's correct or not. If correct then how would I (in code) send that out for each camera to change?

UPDATE

Well I've tried the following code:

int LED_pin = 9; // must be one of 3, 5, 6, 9, 10 or 11 for PWM

void setup() {
  pinMode(LED_pin, OUTPUT); // Initialize pin for output
}

void loop() {
  int dtwait = 1000; // Pause interval, milliseconds
  int V1=20, V2=220, V3=120; // 8-bit output values for PWM duty cycle
  analogWrite(LED_pin, V1);
  delay(dtwait);
  analogWrite(LED_pin, V2);
  delay(dtwait);
  analogWrite(LED_pin, V3);
  delay(dtwait);
}

and just to test it I hooked up 2 green LEDs to digital pin 9 and I can confirm it does light the led's in 3 stages. From bright, medium and then dim-ish.

So I went ahead and powered up the FPV by hooking it up like so:
enter image description here