[systemd-devel] Emulate two cron tab entries to start/stop service unit natively?

[John]

Is it possible to use a systemd timer unit to start and stop a service unit according to set times of the day?  In my case, openvpn.service is a forking type if that matters. I can do this using cron, but am wondering if/how to do it with systemd natively.

In cron terms, one could do this like so:
# start at 7 AM
* 7 * * * systemctl start openvpn.service


# stop at 5 PM
* 17 * * * systemctl stop openvnp.service

The syntax of the timer with differential commands (ie start the service at 7 AM and stop it at 5 PM) isn't clear to me even after consulting `man systemd.time` and `man systemd.timer`.