TF2/Creating Respawning Dispensers
Create Dispensers
Start by placing a few obj_dispenser entities in your map. Name the first "spawned1", the second "spawned2", and so on.
Create point_template
Add an equal number of point_template entities as you have dispensers. Set 'Name' to "template1", "template2", etc. Set 'Template1' to the matching dispenser, so point_template will have 'Template1' value "spawned1". In the 'Flags' tab, tick "Don't remove template entities" to make sure the dispensers spawn on start-up.
Create env_entity_maker
Create an equal number of env_entity_maker entities, one entity per dispenser. Set 'Name' to "spawner1", "spawner2", etc. Set 'Point_template To Spawn' to the matching point_template, so env_entity_maker "spawner1" will have 'Point_template To Spawn' value "template1".

Dispenser Outputs
On the output tab for each dispenser, add these values with the corresponding numbers:
- My output named:
OnDestroyed
- Target entities named:
template1
- Via this input:
ForceSpawn
- After a delay in seconds of:
10
OnDestroyed is not one of the selectable outputs, so Hammer will say this is an invalid output. Ignore that, it will work in-game. Adjust the delay to the number of seconds you want the dispenser to take to respawn.
Now, when your map loads, there should be a set of dispensers, which, when destroyed, make another one spawn in its place.