My HR20-700 just bit the dust, but I have to wait 3 weeks for a service call. I'm going to try and talk D* into letting me pick up a new receiver on my own and give me a credit for it. My local BestBuy has both HR21s and 22s - sounds like the 22 is the way to go, but I'll need to get an AM 21 for my OTA. Does the AM 21 work with the HR22? Thanks.