All these chum-devices are high-tec...
I bring along my laker jigging rod rigged with 20lb braid, a rock, and a lightweight paper bag - like a liquor store bag. Insert chum of choice in bag, add rock, tie bag onto braid, drop bag in hole.
Find bottom, pull bag up about 20 feet by hand, drop half the line out then as it comes tight, yank HARD and break bag. Make sure rock is about the diameter of the bag, and ON TOP of the chum.
Works for me. And I generally save salmon roe through the late summer for this and fish with cured eggs in skein. Add all kinds of anything else that you wish, I have used a lot of the chum items listed above, but the roe seems to provide best results for me.