diff --git a/edosl0util/crio.py b/edosl0util/crio.py
index c125c406f1b6e9bbc311e87caddba65adb8ce218..776978c15a125497bad05b2c7ab33874e9c8846f 100644
--- a/edosl0util/crio.py
+++ b/edosl0util/crio.py
@@ -1,8 +1,8 @@
-
 """PDS construction record input and output"""
 
 import ctypes as c
 import numbers
+
 from edosl0util.headers import BaseStruct, DaySegmentedTimecode
 
 
@@ -51,7 +51,9 @@ def read(cr_file):
     def read_struct(f, struct):
         rv = struct_to_dict(struct.from_buffer_copy(f.read(c.sizeof(struct))))
         rv = {k: v for k, v in rv.items() if not k.startswith('spare_')}  # no spare fields
-        return {k: int(v) if isinstance(v, numbers.Integral) else v for k, v in rv.items()}  # no longs
+        return {k: int(v) if isinstance(v, numbers.Integral) else v for k, v in
+                rv.items()}  # no longs
+
     return main()
 
 
@@ -88,7 +90,13 @@ def write(cr, out_file):
 
     def write_struct(data, struct, out):
         fields = [f[0] for f in struct._fields_]
-        struct_data = {k: v for k, v in data.items() if k in fields}
+        struct_data = {}
+        for k, v in data.items():
+            if k in fields:
+                if isinstance(v, str):
+                    struct_data[k] = v.encode('utf-8')
+                else:
+                    struct_data[k] = v
         out.write(memoryview(struct(**struct_data)))
 
     main()