Philips equipment usually uses their proprietary RC-5 or RC-6 protocol. TiVos use a modified version of the NEC-1 protocol. They're totally different critters.
When I got my first S1, a used Philips, from a fellow Slashdotter whose roommate had moved away to parts unknown and left it behind several years earlier, it came with no remote.
I had a broken DirecTV receiver I got, with its remote, from someone else. It was a Philips. It didn't have all the right buttons, but the TiVo did respond to it in limited fashion.
A little later I spotted a closeout on a Philips universal at Circuit City. TiVo was one of the brands listed on the package.
It lists 2 codes for TiVo, 738 and 838 (on later similar Magnavox universals it's 0738 and 0838). Turns out 738 is for Philips-made TiVos (and also works with SA S2 DTs) and 838 is for the Sony model.
On the same code sheet, in the VCR section, one of the codes listed for Philips VCRs is 738 and one of the codes listed for Sony VCRs is 838.
If the OP already picked up one of those big universals, he/she might as
well give the VCR codes a try before throwing in the towel.
Occasionally I *do* know what I'm talking about.