Sam’s Birthday Puzzle

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Across
  1. 3. It is less for despair and fully for optimistic (4)
  2. 4. Machinery for grinding (4)
  3. 5. Gadgetry without gravity became a disaster (7)
  4. 7. Nothing for romance (4)
  5. 8. Battle arises with retiring Monarch (4)
Down
  1. 1. Improper, United Nations appear left year (8)
  2. 2. Playhouse rate the varied (7)
  3. 6. Welsh capital with sign creates descendants (5)