Here's what i'm trying to do: I would like to use the 622 TV1 to just record HD material while TV2 will be recording SD material. In order for me to do that, I will need my Media Center to be able to change the TV2 via IR instead of UHF. Is this even possible?
The "key" is the colored thingy with the number 1 or 2 on it, you take off the battery cover and slide the key out and turn it over and slide it back in. I'm not sure how this works, but somewhere there is info on it, maybe at Dishnetwork web site.
Take your TV2 remote. If it came with the 622, it should be labeled "IR/UHF Pro 6.3" on the back. Note the word IR. Set the remote channel on it to the channel of TV1's IR remote, but without using the system info screen to change the receiver. It will then give off IR signals (not UHF, line of sight only) that can control TV1 and not TV2.
Thus it is easily established that the remote will in fact send IR signals, contradicting what was posted earlier in this thread.
Now, for the matter of sending IR signals to control TV2 from your media center (and not from your remote control, which is what I am inferring you are trying to do), it should work, but you'll have to have the correct IR codes for your media center to send. This means, among other things, the right codes recorded for the right remote control channel, namely the channel that is shown for TV2 on your system info screen.
So, set your "green 2" remote back to the channel for TV2 and double check it works for TV2 again, then use the learning function on your media center to get the correct IR remote codes for that remote channel.
YMMV, try it with one or two remote codes to make sure it's working before learning all the possible codes.
YMMV because I haven't confirmed that the 622 will LISTEN for IR codes from remote 2, just that remote 2 will send them, but it's worth a test.
I read somewhere that there is a technical limitation that prevents the 622 from receiving IR for TV2 in dual mode. You see, TV1 and TV2, in dual mode, have to be able to operate completely independantly and simulataneously. An IR receiver can only see and respond to a single recognized command at a time. Since it's possible someone on TV2 and TV1 could simulataneously issue a command to the 622, they have to be on seperate receivers. In this case TV1's receiver is IR and TV2's receiver is UHF (thereby, 2 seperate receivers). If Dish had placed two discrete IR receivers on the 622, then you would probably be able to use two IR remotes set to two different channels to control the TV1 & TV2 independantly in dual mode.
The only way that we'll ever be able to use an IR remote to control TV2 in dual mode is if someone creates and IR to UHF device specifically designed for Dish's dual-tuner receivers. This device would be connected to the port where the UHF remote antenna is normally connected and then either be wired into a home IR distribution system or placed somehwhere that the TV2 remote could have line of site with it.
I really wish a box like this would come out, as I do not like Dish's UHF remote's very much (Despite haveing 3 of them to control my 4 TV2's). I use a pair of Home Theater Master remotes (an MX-700 and URC-200) to control my main (TV1) set from the two rooms it's visible from (living room and kitchen/dining). I would really like to put URC-200's in all of the TV2 locations, but cannot since they cannot transmit Dish's proprietory UHF codes.
I think, if dish made this magic box I speak of, they would sell a decent amount of them and could probably charge a premium for them, as custom installers and system integrators, in particular, would use them extensively (and give Dish an edge on getting their systems in high-end custom installations). Of course, they'd sell quite a few of 'em to hard-corps consumers like us as well.
Another option, that Dish could put in their next 'flagship' receiver, is for them to put a "zone 2/TV2" monoplug input for IR on the back of the receiver for IR input from remote locations. This is what makers of multizone home theater receivers (like my Yamaha DSP-AX1) do.
I'd like to hook my slingbox to TV2 output and use the slingbox to change channels by sending IR codes to the box. That would be fun. Would be nice even if there was some way to use remote 1 to control tv2. oh, well.