How to reprogram PSI C-Band satellite receiver

[Monomial]

We never watch TV. We have a 5 year old PSI C-Band system that someone set up for us long ago. His shop is gone.

 

We now want our children to watch the Distance Learning channel for Grade 5 on DLTV channel 44. This is supposed to be 340 on our C Band receiver. The problem is that when we type this in it gives a blue screen which my wife tells me says "Channel not available".  We only get up to channel 338, which is Grade 3.   I am assuming the upper channels have been added to the satellite since our system was installed.

 

We have no instructions for this system, and all messages are only in the Thai language. The box just says "S2 Digital".

 

Does anyone have any idea how to reprogram one of these boxes to add a new channel to the receiver box?

 

[JaiMaai]

 

In Thai but you can try to follow it.