Page 35 Advertisement 1

Radio Record, Volume III, Issue 30, 7 February 1930, Page 35

The {6 39 BLUE SPOT Patent Fowt Pole, Double Balenced Armeture, Driving Unit TYPE 66K Generally accepted by the technical press and trade 28 tbe finest movement available for driving a cone, the Blue Spot Unit stands unrivalled a8 a means of providing faithful reproductiono If you are pushing any particular type of receiver, however good it is, and whatever claims you make for it, you will find that your biggest selling help will be obtained by coupling to it 2 Blue Spot Unit: 66K is essentially a completely discharged 4-pole magnet unit which drives the cone spindle through a perfectly straight line move- ment. The special steel used for the maguet permits of an enornous fux, thus making the unit exceptionally sensitive: The armature -the only part liable to give 2 natural resonance~has been carefully damped and is to all intents and purposes dead silent in action. The unit reproduces all audio frequencies from 50 to 7,000 cycles without giving undlue prominence to either end of the register: 66K has a special adjustor for regulating the gap be- tween the butterfly piece and the four poles of the magnet: Retail Price; 33/6 TRADE PRICES UPON APPLICATION: N.. Agents: RODGER IMPORTING CO, LTD. 159 MANCHESTER STREET, CHRISTCHURCH