Give it time, it's brand spanking new.
Perhaps a better metric would be a view count on (one of) the videos on the new channel vs subscribers. Keep in mind that your main audience is electronics crowd, not space nuts (your first two videos on the channel being space related). While there sure is an overlap, present company included, that is not to be expected for majority of your regular audience. Different interests and all that, perfectly reasonable.
Your next two videos are not related to space, so they will attract a different crowd. Give it time.