Double jump feels really off

Hi there

Pretty new to Unity. I’m messing around, trying to make a simple 2D platformer.

I managed to implement basic movement and jumping. My next challenge was to create a double jump.
It “works” but feels really off. Basically what happens is that the later I press the jump button again, the less I actually jump. So as I’m falling down, I barely get propelled up anymore, if at all. So basically, double jumping only really has an effect at the beginning of a jump. And even then, the result varies.
I want the effect of the jump to be constant and not to be dependant on my current jump arch.

Here’s the code that is relevant to moving and jumping. Note: A lot of the code stems from this video right here.

    int count = 0;
    public Text countText;
    public Text winText;

    float maxSpeed = 10f;
    public float jumpForce = 70f;

    bool isFacingRight = true;
    private Rigidbody2D rb;

    bool grounded = false;
    public bool doubleJump = false;
    public Transform groundCheck;
    float groundRadius = 0.2f;
    public LayerMask whatIsGround;
    Animator anim;

	// Use this for initialization
	void Start ()
        rb = GetComponent<Rigidbody2D>();
        anim = GetComponent<Animator>();
        winText.text = "";
	// Update is called once per frame
	void Update ()
        if ((grounded || !doubleJump) && Input.GetButtonDown("Jump"))
            anim.SetBool("grounded", false);
            rb.velocity.Set(rb.velocity.x, 0);
            rb.AddForce(new Vector2(0, jumpForce));

            if (!doubleJump && !grounded) doubleJump = true;


    void FixedUpdate()
        grounded = Physics2D.OverlapCircle(groundCheck.position, groundRadius, whatIsGround);
        anim.SetBool("grounded", grounded);
        if (grounded) doubleJump = false;

        float move = Input.GetAxis("Horizontal");
        anim.SetFloat("Speed", Mathf.Abs(move));
        rb.velocity = new Vector2(move * maxSpeed, rb.velocity.y);

        if ((move > 0 && !isFacingRight) || move < 0 && isFacingRight) Flip();

Is there any way I can improve my double jump so that it feels more like in other games and isn’t affected by how fast down I’m currently going? (i thought rb.velocity.Set(rb.velocity.x, 0); would fis this but apparently not…)

So, I found out what the problem was.
I replaced

rb.velocity.Set(rb.velocity.x, 0);


rb.velocity = new Vector2(rb.velocity.x, 0);

And now the double jump isn’t affected by my fall.