diff --git a/app/internal/types.py b/app/internal/types.py
index e90a3a2..bf7127d 100644
--- a/app/internal/types.py
+++ b/app/internal/types.py
@@ -43,7 +43,7 @@ class System:
             avail_on_nodes: A list of node identifiers where this is available.
             description: A brief description.
         """
-        self._id: str = _id
+        self._id: str = str(_id)
         self.type: DemodTypes = _type
         self.name: str = name
         self.frequency_khz: List[int] = frequency_khz