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  1. square wave tdr.jpg

    square wave tdr.jpg

    5v square wave TDR using 74AC14 schmidt trigger oscillator.
  2. 2n3904 TDR.jpg

    2n3904 TDR.jpg

    Avalanche pulse generator TDR using a 2n3904 inside a capped off PL-259 coupling ring attached to a TNC to SO-239 adapter (because I didn't have a BNC to SO-239 adapter) with high voltage supply.