Richard: To program my Apex PF2720 TV remote (CK5D-C1) I had to: 1.> Set the side switch to TV. (the switch labeled TV, DVD/VCR. SAT/CAB, AUX) 2.> Press & hold SET switch for over 3 seconds (until LED light goes off)then release SET switch (LED light will come back on) 3.> Immediately key in Apex TV code (in my case 157) and press the ENTER key 4.> The remote is now reprogrammed for the TV. The manual gave the TV codes for Apex TVs as: 157, 158, 159, 160, 161, and 162. the 157 key worked for me and I have not tried any of the others. You should be able to download a manual free if you search for it. Hope this helps.