Turn on logging without archive?

A had occasion the other day to want to turn on logging on an On-line 5.0X database for a short time. I simply wanted to test some code using transactions, and only neeeded the logs for a short time. Knowing that the procedure was to create an archive first, I duly did same and then started the logging....but I got to wondering, during the hour of the archive, whether there is a simply change I could make to the system catalogues to short circuit the process. If there is, are there any pitfalls when the contents of the logs are unimportant? Bryan Tonnet