Pilot Dual Radiogram Model Unknown |
Written by Bryce Ringwood |
This radiogram was made in 1963 and the only information on the set was that it was a “Dual”. The radiogram has a Garrard deck with a stereo crystal pick-up. It has separate FM and AM tuners – which I think is unusual for a set of this period. It has a multitude of inputs and outputs for speakers and tape decks. Perhaps the most unusual feature is that each half of the stereo amplifier can be used independently for AM, FM and the gramophone. Thus, you could, in principle, be listening to AM with your left ear and FM with the right.
I think the idea was so that you could have speakers in different rooms with different stations on each. The set was in very nice condition, so I spent a bit of extra time cleaning up the chassis. Technically, the FM tuner consists of an ECC85 VHF RF/Mixer/Oscillator followed by two EF80 the first being an IF Amp, the second being a limiter. FM detection was carried out by germanium diodes. The AM section consisted of an ECH81 Mixer/Oscillator followed by EBF89 IF Amp/Detector. There was also an EC91 triode valve carrying out some unknown function (I couldn't locate the model, so I couldn't find the circuit diagram). Maybe the EC91 was the local oscillator, and the triode of the ECH81 was a buffer – but I didn't trace the circuit, so I don't really know. The stereo amp consists of two identical amps using half of an ECC83 and an EL84. Power supply rectifier was the EZ81, now made by JJ valves, who also make all of the audio valves in this set. Also made by JJ, but not in their web catalogue, is the EM84 tuning indicator used in this set.
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