recently I ran into an issue which required me to adjust some settings in my TV's service menu and that made me realize what a hassle it can be to track down that code for a specific model, especially since the service manuals weren't handed out to the end users back in the day. (And especially if you want to avoid some shady sites on the web that claim to offer the manuals for money).
I'll start with the Sony Trinitron KV-29ls60e whose manual I found.
Does anybody happen to have the codes for the Philips Models 28PT7128/12 and 28PT4457/01?
SONY
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Trinitron KV-29ls60e
[Prepare remote commander for Service mode]To return remote to normal mode, repeat steps 1 and 2, then press 0 0 0 0 0 -> all three LEDs should light and remote be in normal mode again
- Press VCR / TV / DVD button until TV LED lights
Press & Hold yellow button until TV LED flashes quickly
Press 9 9 9 9 9 -> all three LEDs should now light and the remote be in Service Mode.
Setting TV to Service ModeWhen done, switch TV off and on again.
- Program remote commander for service mode as described above.
Turn on TV main power switch
Press Video Standby button on remote twice
TT__ will appear in upper right corner of screen
press menu