The R.I. Airflo 451 — often written “Airflow 451” — is a British valve radio made by Radio Instruments Ltd. of Croydon, Surrey, shortly after the Second World War. Contemporary catalogues list Radio Instruments’ proprietary radio names as Airflo and Aria.
Valve Lineup
- TH41 — mixer-oscillator
- VP41 — IF amplifier
- HL42DD — detector, AGC and first audio amplifier
- Pen45 — audio output pentode
- UU6 — full-wave mains rectifier
The service manual for this radio is available in the Members’ Area here.
