The testing of cathode ray tubes for use in the Williams type storage system

This paper describes a series of tests which we have used at Manchester for Williams type cathode-ray storage tubes (type VCRX266) The majority of the tests are functional rather than analytical. They have the advantage of indicating immediately whether a particular tube is fit for use, although it is true that functional tests give less help than analytical tests in tracking the causes of faults. The tests described are at present carried out by an engineer using test equipment which will be described in outline. The equipment has been made for use by Messrs. G.E.C. of Wembley, England, who are the suppliers of the tubes. It is hoped to reduce the test procedure to a routine that can be carried out by less skilled workers.

A paper of this kind must inevitably dwell to some extent on the pathology of storage tubes, but it should be recognised that many of the faults mentioned are rare. A table will be given showing the numbers of rejected tubes in two batches which have been tested. In order to quote examples of some of the rarer faults it has been necessary to include as one of these batches a collection of old tubes many of which were rejected as unfit for use at a time before systematic tests were begun.