That remote was used with the Zenith ST-1000 series TAC cable converters. I believe they were 465 KHz modulated Ir remotes with 3 high output LEDs in the front. You can not only use them as a remote but also as a hammer, window prop and classroom disruption device in schools that use older Zenith sets... Been there done that. They also have a very long range and the reference ceramic can be changed to 455 KHz to make it work with other Zeniths as the digital commands are the same but carrier rates are different.
Kind of a late reply but I've played with many of these and upset many a teacher with them!

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