Difference in 30,40 and 50

30 and 40 use waas correction. Free government satellites same as airplane use for autopilot. 11 satellites is the best it can get average 9 at a time.

50 uses waas and GLONASS. GLONASS is satellites owned by the Russian government. That brings an additional 11 satellites into view giving a total of 22 SAts with average tracking being 16. The 50 also moved the sat reciever back to top of collar giving better GPS reception. Same as 30's.

Now to units.

220 can track a 30 or 40. Great unit but outdated.

320 can track 30, 40, and 50. Also offer birds eye map which is real nice having Ariel view maps like google earth. Also a great unit. Not exactly outdated yet but with electronics that could happen tomorrow.

The limiting factor of both units when it comes to range is the radio signal. If ur unit can't get info from collar all the satellites are useless. Long range antennas are the best investment u can make for ur tracking system. Both on the collar and handheld. I use the long factory supplied antenna on my handheld and long range ones on my collars. I also have an extendable antenna I can use on the handheld. It makes a huge difference in tough conditions. I would like the cb style mounted antenna. It gives u a larger ground plane increasing the receiving effectiveness of ur hand held. This with long range antennas would give u the best communication between handheld and collar.

I have never laid hands on an alpha so can't give any input on it.

Shotgun
Arkansas