Frequency-control components are among the least visible and least substitutable items in a satellite. An oscillator sets the time base against which a payload measures, a receiver correlates and a transponder transmits; it is small, cheap relative to the platform, and almost impossible to change late in a programme without consequences that propagate through the design. For European space capabilities with defence relevance, this combination makes the segment a useful test of what industrial autonomy actually means. The intuition most procurement and policy discussions bring to it — that several manufacturers, or several European factories, amount to resilience — is precisely the intuition the evidence does not support. What matters is not how many companies exist but how many approved paths exist to the same requirement, and those paths are defined by a qualification system whose rules are about to change. The question worth asking is therefore narrower and harder than a supplier count: when does a European-located source constitute usable industrial capacity for an approved space configuration, and when would moving to another product, process, site or corporate owner require fresh qualification, customer approval or redesign before it could serve as an alternative at all?