Wrapping up my theater in the basement and now trying to figure out the RF/IR situation. I am going to have a Panasonic AX100u projector mounted on the ceiling and the rest of my components in an A/V cabinet (with doors) in another area. I have run a 50' 1/8 type cable that an IR blaster will plug into for my projector.

My question is, does the 890 RF emitter have the ability to control my projector (e.g. does it accept standard 1/8" inputs?), or am I going to have to go with the MX900 with MR300?

Also, does the 890 RF emitter have a max blaster of 6, if so this may not work.

I currently have a harmony 688, and besides the battery holder not staying on right, it mostly does what i like and my wife knows how to use it.

Yes, the H890 RF extender uses standard 1/8" inputs. It comes with 4 twin emitter units and it has four jacks, so if you use both of the emitters on each 1/8" input, you can control 8 devices via the jacks on each RF extender. If, however, you only use 1 emitter on each cable, then you will only be able to control 4 devices via the jacks on the RF extender. Obviously, any combination of using both emitters or single emitters up to 8 devices will work. e.g. since you are dedicating one emitter cable to your front projector, you could control up to 6 additional devices if they were close enough physically (and it sounds like they are) to use both emitters on the other three emitter cables. Also, the RF extender has a built in IR blaster in the unit itself so it can send IR signals to anything that can see the IR coming directly from the built in IR blaster. I can't remember now but it seems like I remember the maximum number of devices that the H890 can control is like 15--you need to check the specs on this to confirm if you have more than 8 or 9. I currently control 9 devices with mine, 8 using the RF extender and one using IR direct from the remote itself.

I'm creating a similiar setup with an ax100u, and also debating on the Harmony 890 and the universal mx-900. I would like to control lighting, and I'm not sure the mx-900 can do it, but I've heard alot of negatives about the 890. Help! Any suggestions.

Lighting control is a function of whether the system you're using can be controlled via IR. The 890 and MX-900 are equal in their ability to control lighting (unless the lighting is Z-Wave controlled, in which case the 890 could do it where the 900 couldn't). Most Lutron systems can be IR controlled and X-10 can be as well with the use of an IR543 IR to X-10 converter.

I would like to get the rf extender. Could this control a dimmer or light switch. How would the ir work without line of sight.

Dcfam