At hifi-remote, there are 3 Advent TVs listed. Model Q328A responds to NEC protocol, device 8,8. Models HT2715A and Q2035A respond to RC5 device 0. Philips TVs use RC5, but apparently none have the same function numbers as the Advent.
If you go to www.getzweb.net/jp1/
, you can do a brand lookup for Advent. Various protocols known to work with Advent TVs are listed, and the setup codes that would be used with remotes made by Universal Electronics. If you have a Comcast, Time Warner, Cox cable remote, or One For All, some Radio Shack, some RCA remotes, then you may be able to enter in the relevant setup code, and get control.
If you want to try using the MB, you could click on the EFCs link for any protocol and find a list of brands which use that protocol, device numbers, and function numbers. For example, if you click on EFCs link in setup code 0761, and click the brands link, you'll see that this setup code is used by Advent, Jensen, and Prima. Perhaps you'll find one of those brands in the MB lists.