Difference in 30,40 and 50

If your buddy's alpha is having problems at that rang, something is wrong try updating the unit and collars. the alpha is the best of the best hands down, distance and performance. look at it like this....

astro 220 was the best first.
then the 320 came out and was evan better. and the 320 is compatible with all the same collars. 30's 40's and 50's.
now theres the alpha and it is the best by far. kinda a all in one. but these collars wont work with it you need the new collars TT10

the collars are the same way 30's were first and the best at that time. then the 40's came out they were evan better, then the 50's came out and they were the best.

now with the new alpha and TT10 collars, don't look for any new collars for the Astros like 60's or 70's because the new technology will all be for the alpha, yes garmin is phasing out the Astros and the collars 30 40 and 50.

with this being said buy the best that you can afford. and at this time the best system is the alpha (hints the price)

hope this helps . and for the record this is just my opinion!!!!!!!!