Weight, balance, and string tension convert in both directions. Swingweight is estimated from weight and balance, not read from a machine.
Weight
Balance
7.2 Head light
String tension
Swingweight estimate
About 319
Where most stock frames sit
The estimate treats the frame as a point mass at the balance point, then adds a distribution typical of a modern racket. 300 g at 320 mm lands near 319. A machine reading still comes from an RDC.