Page 29 Advertisement 2

Radio Record, Volume III, Issue 18, 15 November 1929, Page 29

The 91 BLUE SPOT Patent Four Pole, Double Balanced Armatures Driving Unit TYPE 66K Generally accepted by the technical press and trade a8 the finest movement available for driving 8 cones the Blue Spot Unit stands. unrivalled a8 a means of providing faithful reproduction: If you are pushing any particular type Qf 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 a 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 uged for the magnet permits of an enormous fux, tbus making the unit exceptionally sensitive: The armature_the only part liable to give a 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 undue prominence to either end of. the register: 66k hag a special adjustor for regulating the gap be- "tween the butterdly 'piece and the four poles of the magnet: Retail Price; 3216 TRADE PRICES UPON APPLICATION: N Agents: RODGER IMPORTING CO- LTD. 159 MANCHESTER STREET; CHRISTCHURCH