Hey Stern,
I use a Humminbird "Fishin Buddy".It is a portable unit that will clamp to the gunnels of a canoe (my first use), or a dock.It clamps with an oversize "C" clamp.I use it on the ice by lying the c clamp on the ice and sliding the unit through its retaining collar and into the hole.It's certainly not as accurate or responsive as a Vex or Humminbird Ice flasher, but it does indicate when fish are in the area.Certainly low tech but I find it helpful.