With the old meter you can get a lock around 40% however the slightest rain will knock it out everytime. Some transponders will read a stronger signal while others will read a weaker signal. Just because you barely get a lock on one does not mean you will get a lock on another. When you start getting around 50-60% on any given transponder you will experience a lock on all of them in most cases. This is with the old signal strength readings.