And now for something completely different.

Passing the Swindon Scrapstore the other day I happened upon a Ferranti U1015 valve radio. Unable to resist renewing my acquaintance with thermionic valve technology I had to buy it. The radio worked in a fashion, and combined with its shabby and neglected condition it was not going to be a great loss to me at £5.
Getting it home I remove the years of dust from the inside, re-stuck the front face material and cleaned off the flaking paint from behind the tuning scale. (It was my intention to mount the chassis in Perspex to allow the glowing valves and primitive circuitry to be seen whilst in operation. The heat generated by the four vales, over time on the Perspex, was going to be a no no).
Turning to the intermittent slower than normal warm up time of the radio the fault was eventually traced to an unsoldered well hidden through connection on pin7 of V1. (This had no doubt been ‘fixed’ in the past by the usual bash of the radio).
A later intermittent fault resulted in the loss of the LW. Replacement valves proved no solution. Eventually the fault was traced to weak spring pin contacts in the base of V1. A replacement V1 base was sourced from China!
A circuit diagram was obtained off the Net in the form of an Ekco U332 whose chassis was also sold under the Ferranti name.
So it seems I have a superheterodyne receiver with V1 (triode heptode) operating as a local oscillator and frequency changer, V2 (double diode pentode) as demodulator and automatic gain control rectifiers combined with an intermediate frequency amplifier, V3 (triode pentode) as an audio frequency amplifier and output stage, V4 (diode) as a half wave rectifier. The apprentice school memories came flooding back.