Would love to find a manual for an IT-21 tube checker. Can anyone help? Reply to jhsproul at msn.com. Thanks. Listserver Subscription:listserv at listserv.tempe.gov - "subscribe heath 'name' 'call'" Listserver Submissions: heath at listserv.tempe.gov Listserver Unsubscribe: listserv at listserv.tempe.gov - -"signoff heath"