We are switching to satellite again. (Cable is just crap). To get the local channels and to get some HD programming I need to hook up an external antenna. If I bring the external signal in and route it through the sat box will I end up filtering out the HD signal and just end up with regular signal? This is with a Dish 301 receiver which has antenna in and co-ax out. Finally to try and get the best picture from all my components I came across a phone/RCA jack to S-video converter. If I use this from my non-S-video VCR is it likely that I will experience any performance enhancement? Thanks!