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Doctor Wilker is experienced in a unique variety of electronic sciences, including but not limited to communications, robotics, and computational technologies.
Wilker builds and constructs the Muffit II robotic daggit as a favor to Apollo, programming it for Boxey's visual image that Apollo furnishes him. He had hopes to use the Muffit II as a template for other daggits to take watch over the Warriors as they rest in situations where they are isolated or on a ground mission (Saga of a Star World).
Apollo later questions Wilker on the possibility that Iblis is an android construct, and Wilker mentions (interesting and ironically enough) that such a feat is possible with Colonial technologies. He later is sent on a mission to find out what exactly caused the "miracle" growth of the edible plants on the Agro Ship Nine, during Iblis' visit to The Fleet. He discovers that the plants had been subjected to a growth-inducing radiation (War of the Gods).
Additionally, he apparently is also on call to do forensics for the Fleet, as he tests Starbuck's laser pistol to confirm whether or not the energy expended upon Ortega's corpse is the same as the energy expended from Starbuck's pistol. Unfortunately, it is, albeit it is later proven that Karibdis had terminated Ortega using the pistol while Starbuck was showering (Murder on the Rising Star).
Wilker also is responsible for experimenting with the Lunar Seven shuttle that Michael liberates from the Eastern Alliance, although he tends to be over the line in his experiments, and is ordered by Adama to desist (Greetings from Earth).
Boomer noted that Wilker could do thousand-fold better than him to clear up the transmission that Apollo receives in the old Gamma frequencies, although he apparently is over at the electronics ship (the Celestra, most probably) at the time. Wilker never has the chance to look at it, since his lab is destroyed when Galactica fences with the lone Cylon base star that Apollo and Starbuck blind (The Hand of God).