one call away

away：距离多远

one call away=一个电话那么远

"不管多远，一个电话我就到"

If you need my help, remember I'm just one call away!

需要帮助的话，记住我随叫随到。

Don't be too sad that I'm moving. I'm just one call away!

别为我搬走难过，一个电话我就过来。

(to be) on call

既然可以“随叫随到”，想必一定是“得空”了～

be available to sb

He was available to me morning, noon, and night.

早上中午夜晚，他随叫随到。

No, she's not available.

不，她现在没空。

I’m your man.

If you need someone to help fix the car,I’m your man.

如果你需要有人帮你修车，我就是你要找的人。

出处：喜阅英语（自媒体号）