Problam - Using Multiple Maxsonar sensors

hi all,
i am new in the world of arduino

i have two sensors of type 'lv-maxsonar-EZ'

i want to chain them together.
in the datasheet of the sensor i understood (and i could be wrong)
that i need to connect the TX from the 1st sensor to the RX of the 2nd sensor
and to connect the Tx from the 2nd sensor to the Rx of the 1st sensor

now there is no signal at all

i think that maybe i should connect the Rx from the 1st sensor to somewhere in the arduino?

i would really like for an help from you guys.

thank you
(and sorry if i have spelling mistake)

Interesting device. LV-MaxSonar®-EZ™ Series

I've created a sample diagram and sketch that could get you started (untested).

AN Output Constantly Looping:

int startPin = 2;                 // startup pin
int sonar1Pin = A0;               // sonar1 pin
int sonar2Pin = A1;               // sonar2 pin
unsigned short value1 = 0;        // variable for sonar1 reading
unsigned short value2 = 0;        // variable for sonar2 reading
unsigned short intervalR = 50;    // read interval
unsigned short intervalP = 1000;  // print interval
unsigned long previousP = 0;
unsigned long previousR = 0;

void setup() {
  pinMode(startPin, OUTPUT);
  digitalWrite(startPin, HIGH);
  delay(1);
  pinMode(startPin, INPUT);
  Serial.begin(115200);
}

void loop() {
  unsigned long now = millis();

  if (now - previousR >= intervalR) {
    // double read to ensure accuracy
    value1 = analogRead(sonar1Pin);
    value1 = analogRead(sonar1Pin);
    value2 = analogRead(sonar2Pin);
    value2 = analogRead(sonar2Pin);
    previousR = now;
  }

  if (now - previousP >= intervalP) {
    Serial.print("Sonar1 = ");
    Serial.print(value1);
    Serial.print("\tSonar2 = ");
    Serial.println(value2);
    previousP = now;
  }
  // your code
}