That's good thinking. I'm a software developer myself, and as such I'm a big believer in the logical solutions to problems.
So if I was to write the algorithm behind this quest, I'd want it to be rare but not impossible, based on the likelihood of players stumbling across it or, as in our case, some dedicated investigation.
Since the introduction of WSS and SSS, the likelihood of getting a signal that contained items seemed pretty high. The wings update introduced the concept of these more difficult signals, the 'Strong' ones, which contain either -
a convoy or funeral ships - scanning these ships returns either nothing, normal trade items or occasional 'rare' items
a small battle between system authority vessels and pirates - scanning the pirates reveals normal trade items (probably stolen)
just pirates
although I haven't seen any of these since the last update, occasionally I have experienced a few canisters of rare items (or more likely gold) and a couple of anacondas that pop in and say something like 'I can't believe that worked!'
USS sources (Unknown Signal Sources) seem to contain either -
a single large ship (The Mineral Merchant or whatever that Type 9 is called)
a single small ship (pirate or trader), may carry normal trade items
two or more smaller pirate ships
nothing (this may be a bug?)
WSS (Weak Signal Sources) only ever contain a destroyed ship, and canisters of none-tradeable items (i.e items you cannot buy at a market) such as (but not limited to)
Rebel Transmissions
Black Box Recorders
Ancient Artefacts
Toxic Waste
etc etc.
The likelihood of a signal appearing in supercruise must be tied to certain parameters. So these could be -
A system specific flag - relating to size (population), type (Anarchy, democracy etc) or some other flag - for instance as we have tried, certain systems might be more likely to cough up these Unknown Artefacts than others, or maybe some sytems won't have them at all.
A Location flag relating to the system - near a star port, deep space, near a star, near a planet, near a RES or a belt.
User specific flags - speed - are you more likely to come across a signal source when you are going faster, or slower?, mission specific (I'm looking for Rebel Transmissions for instance, make it more likely to be in the type of SS found), ship size / cargo size (I don't think I've ever come across a number of canisters that are more numerous than my cargo bay)
Time specific flags - time since last SS found, number of SS's currently spawned (that old myth about the items you are looking for are always in the
second USS that appears
)
So, from what we have found so far -
SS's are more likely to appear in populated systems.
Weak signal sources are the least likely to appear out of all of them
Weak signal sources are the most likely source of Unknown Artefacts.
So as Ermius says, get in to a large populated system and scan those WSS's
