diff --git a/vars/default_vars.yml b/vars/default_vars.yml
index 068a9df66..90fbf7ca8 100644
--- a/vars/default_vars.yml
+++ b/vars/default_vars.yml
@@ -43,6 +43,9 @@ download_timeout: 200
 default_language: en
 language_priority: en es fr
 
+# Real-time clock: set RTC chip family here.  Future auto-detection plausible?
+# rtc_id: ds3231
+
 # Set iiab_admin_user_install: False if you don't want iiab_admin_user & wheel
 # group auto-created in roles/iiab-admin/tasks/main.yml (hence disabling sudo-
 # checks/warnings of published passwds like pi/raspberry & iiab-admin/g0adm1n).
diff --git a/vars/local_vars_big.yml b/vars/local_vars_big.yml
index 116c65daf..24ef93c34 100644
--- a/vars/local_vars_big.yml
+++ b/vars/local_vars_big.yml
@@ -15,6 +15,9 @@ download_timeout: 200
 default_language: en
 language_priority: en es fr
 
+# Real-time clock: set RTC chip family here.  Future auto-detection plausible?
+# rtc_id: ds3231
+
 # Set iiab_admin_user_install: False if you don't want iiab_admin_user & wheel
 # group auto-created in roles/iiab-admin/tasks/main.yml (hence disabling sudo-
 # checks/warnings of published passwds like pi/raspberry & iiab-admin/g0adm1n).
diff --git a/vars/local_vars_medium.yml b/vars/local_vars_medium.yml
index a3d36f19f..b8f66307b 100644
--- a/vars/local_vars_medium.yml
+++ b/vars/local_vars_medium.yml
@@ -15,6 +15,9 @@ download_timeout: 200
 default_language: en
 language_priority: en es fr
 
+# Real-time clock: set RTC chip family here.  Future auto-detection plausible?
+# rtc_id: ds3231
+
 # Set iiab_admin_user_install: False if you don't want iiab_admin_user & wheel
 # group auto-created in roles/iiab-admin/tasks/main.yml (hence disabling sudo-
 # checks/warnings of published passwds like pi/raspberry & iiab-admin/g0adm1n).
diff --git a/vars/local_vars_min.yml b/vars/local_vars_min.yml
index 038c496f1..8918cd634 100644
--- a/vars/local_vars_min.yml
+++ b/vars/local_vars_min.yml
@@ -15,6 +15,9 @@ download_timeout: 200
 default_language: en
 language_priority: en es fr
 
+# Real-time clock: set RTC chip family here.  Future auto-detection plausible?
+# rtc_id: ds3231
+
 # Set iiab_admin_user_install: False if you don't want iiab_admin_user & wheel
 # group auto-created in roles/iiab-admin/tasks/main.yml (hence disabling sudo-
 # checks/warnings of published passwds like pi/raspberry & iiab-admin/g0adm1n).
diff --git a/vars/raspbian-10.yml b/vars/raspbian-10.yml
index 999ed0dac..1f156a007 100644
--- a/vars/raspbian-10.yml
+++ b/vars/raspbian-10.yml
@@ -3,7 +3,6 @@ is_debian: True
 is_debian_10: True
 is_raspbian: True
 is_raspbian_10: True
-rtc_id: ds3231
 
 # 2019-03-23: These apply if-only-if named_install and/or dhcpd_install are True
 # (This is quite rare now that vars/default_vars.yml sets dnsmasq_install: True)
diff --git a/vars/raspbian-8.yml b/vars/raspbian-8.yml
index c27a6111c..1d5e190e3 100644
--- a/vars/raspbian-8.yml
+++ b/vars/raspbian-8.yml
@@ -3,7 +3,6 @@ is_debian: True
 is_debian_8: True
 is_raspbian: True
 is_raspbian_8: True
-rtc_id: ds3231
 
 # 2019-01-31: These apply if-only-if named_install and/or dhcpd_install are True
 # (This is quite rare now that vars/default_vars.yml sets dnsmasq_install: True)
diff --git a/vars/raspbian-9.yml b/vars/raspbian-9.yml
index f64d9d93b..069afaac9 100644
--- a/vars/raspbian-9.yml
+++ b/vars/raspbian-9.yml
@@ -3,7 +3,6 @@ is_debian: True
 is_debian_9: True
 is_raspbian: True
 is_raspbian_9: True
-rtc_id: ds3231
 
 # 2019-01-31: These apply if-only-if named_install and/or dhcpd_install are True
 # (This is quite rare now that vars/default_vars.yml sets dnsmasq_install: True)