I have a slimline dish and a H20-600 rcvr. have been getting all the birds fine. Have got good signal levels of 97 or above on all working transponders on the 99, 101,110,and 119 degree birds on my receiver. have zero level on the transponders on the 103 bird as shown by my h20-600. I realigned the dish with my Bird Dog and it was still perfectly aligned. Any suggestions of what else to try, I don't have another receiver to swap out