Period of a particular Cycle for a Bessel Function

Question

The Bessel Function of the First Kind $J_a(x)$, and the Bessel Function of the Second Kind $Y_a(x)$, at least when $a$, is an integer or half integer are cyclical, as their values go from positive to negative and from negative to positive an infinite number of times as $x$ increases. They are not periodic however as the period length, in which $J_a(x)$ or $Y_a(x)$ are positive, or in which $J_a(x)$ or $Y_a(x)$ are negative is not the same for every cycle. For the nth cycle of $J_a(x)$ or $Y_a(x)$, in which n is an integer, is there a formula for the period length of that cycle?