For each sat channel 'looked at' you will need a LNB and cable to a 'tuner'
So to achieve the desired result you will need at least a triple LNB[if such tings exist or another dish/LNB/cable
1.SKY 2 Humax to watch 3 Humax to record.
Getting the idea?
Speak to your installer.
But I guess a Google for a satellite publication my be a better place to look
look here for example