Amiko Mini-Combo Box Query

About two years ago, I decided my Sky subscription had to go because as much as I loved the ease of it, the cost was just getting too much and I had to reassess finances. So when I decided to go to free to air, a friend recommended someone who installs free to air boxes and as luck would have it, we were getting work done on the roof so he was easily able to shimmy up and make the adjustments to the satellite dish. So far so good.

However, he wasn't much for sharing information about the boxes and what is entailed with setting channels - I'm not super techie but I like to know things and I like to learn - and so for the second time, I've lost channels and the only way I know to get them back is have him arrive with his memory stick and upload them. (If he answers his phone). Is there a way I can do this myself, retune it? I'm not trying to do anyone out of money but the whole point of getting free to air was so that I would have something that would be relatively low hassle and that I could sort out myself. If I can't, fair enough. (But I'm not in a hurry to get him back because when I asked about recording shows or getting a box that could, he started telling me to use the BBC iPlayer and the like and then started explaining VPNs to me. Which...I know what a VPN is, I have one, and he very pointedly changed the subject afterwards).

Query the second: the last time he was here, there was a problem with the power cord and so he changed it to one with a two prong plug which he duly plugged into a regular extension lead. Only the other day I had to unplug it and now the two pins are bent and I can't plug in my box. Can I replace the power cord? Who do I ask? Should I stick with the Amiko or look at a new box?

I'm asking here because I've been trawling the threads (y'all have a lot of information, fair play, it's very interesting even if I'm a bit lost at times) and I honestly have nobody else in RL to ask.