Texas Instruments Video Modulator Model UM1381-1 for TI-99 not tested

Texas Instruments Video Modulator Model No. UM1381-1 - TI-99/4A

UM1381-1 VIDEO MODULATOR ADAPTER TEXAS INSTRUMENTS

RF Adapter Video Modulator UM 1381-1 TI-99 / 4A Texas Instruments Computer

Texas Instruments Model UM1381-1 Video Modulator RF Adapter for TI99/4A Computer

Texas Instruments Video Modulator Model UM1381-1 for TI-99 VTG. not tested

Vintage Texas Instruments Video Modulator UM1381 TI-99/4A Untested PARTS.