The Etronic RA640 a.c mains valve radio was made in 1948, by the Hale Electric Company, Limited, West Ealing, London W13. The price was £21 13s 9d (inclusive of Purchase Tax), and £17 17s 0d (before Purchase Tax).
The set is housed in a very attractive wooden cabinet. The control knobs (left to right) are on/off & treble, wavechange, tuning, and volume.
The radio can receive Short Wave Bands (15 to 51 Metres), Medium Wave Band (190 to 550 Metres), and Long Wave Band (900 to 2200 Metres).
The Valves used in this set are of International Octal Types 6K8G (Frequency Changer), 6K7G (I.F Amplifier), 6Q7G (Double Diode/ Audio Pre- Amplifier), 6V6G (Power O/P), 5Z4G (Rectifier), and Y63 Tuning Indicator (can be replaced by EM34 with modifications).
I bought this set from a house clearance shop in York, a few years ago. The tuning mechanism on the set was really stiff to move about, so I set about repairing it. I removed the dial glass and then the backing plate to gain access to the dial drum and dial cord. The spring was in a poor condition. I greased the tuning spindle (which was very stiff). I then set about re-stringing the dial cord (luckily, I had the Etronic service notes, which showed the cord layout). I found that the old cord was a bit worn out, and I did not have access to some thicker cord, so I used some thinner R.S type, and a new spring. The results were excellent. I applied some "Copydex" glue to where the cord goes through the pointer clips, and also to where I had tied the knots to the spring (before stretching it on to its locating spigot on the gang drum).
I changed the 220K ohms resistor to the anode of the 6Q7G valve, and the coupling capacitor to the grid of the 6VGG valve.
There were some other Sprague metal caps to change.
I installed a 3-core mains lead to the set, which earthed the chassis (the set uses a double wound mains transformer, which makes this operation o.k). I also put a replacement 25k lin pot with double pole mains switch (the original one had a single mains switch). Some care has to be taken in this area of the set, as the switch is relitively near to a bracket that is secured to the chassis. I covered the switch terminals in order to avoid contact with them.
Some of the knob springs were a problem when replacing the control knobs back on the shafts. They were a bit loose on fitting. Even installing new springs did not solve the problem, so I put some "Copydex" glue inside the knob, and on the shaft to give it some secure holding (the knob can be removed for future access to the inside).
The set works well now on all bands. The Etronic logo on the dial, is really impressive. It portrays an era when Britain had some "pride" in its products