12v relay has coil resistance 70ohm want to wsitch using mega arduino

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1

i have attached my circuit connection in attachment. i am tryong to use 12v relay with arduino. as per my knowledge it needs 70mA and arduino cant give more than 40mA. so i used a fet sl100. i have also used doide in4007 reverse. relay switches perfectly but when i check the voltage at the pin of micrcontroller it shows 1v instead of 5v. is it k?
can i go ahead or shud i do sumthing else??

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2

instead of microcontroller signal if i givee 5v from microcontroller pin it works n styas 5v but if i try to give from digital pin it shows 1v only

3

but at same pin if try to run the blink program it works n shows me 5v n 0v.
if i remove connection from the board my pin shows 5v.
now my prog section which tells the pin to go high if my serial datastring 3 = 5 is:

if (inData[3] == '5' ) // TONE ATENUATOR SELECTION RELAYS
    {
    digitalWrite(tonerelay[0], 1);
    digitalWrite(tonerelay[1], 0);
    digitalWrite(tonerelay[2], 0); 
    }

in my prog i am doing seriall comm:
my complete code if req is attaced.

full_prog_without_print_tone_special.ino (11.6 KB)

4

IS anybody there???

5

I'd have thought that the output pin of an arduino should be able to drive that transistor quite easily.
Have you included the line
pinMode(tonerelay[x],OUTPUT);

6

I used DDRD, DDRC PROG :
i declared port as o/p port:

DDRC = 0xff;// PORTC TONE INTENSITY PORT DECLARED OUTPUT PORT