An adrenergic receptor signaling pathway that contributes to an increase in frequency or rate of cardiac muscle contraction through phosphorylation and enhancement of the ryanodine receptor, a calcium-activated calcium-release channel found in the membrane of the sarcoplasmic reticulum. An adrenergic receptor-activated adenylate cyclase generates cAMP. cAMP then activates the cAMP-dependent protein kinase A (PKA), which phosphorylates the ryanodine receptor (RyR). PKA-phosphorylation of RyR enhances channel activity by sensitizing the channel to cytosolic calcium. Cytosolic calcium stimulates contractile proteins to promote muscle contraction.