instrument number PV12018
GEC model BC5442 Five valve table radio housed in a veneered wood case with gold expanded metal speaker grille. Valve line up: X79, W77, DH77, N78 and U78. AC 190-250V 40-100Hz. 3 wavebands (Short 13.5 50m Medium 186-572m and Long 1000-2000m)
Although the radio has an in-built frame aerial attached to the inside of the rear cover but there are also sockets for the optional connection of an external aerial and earth. UK first produced in August 1951 when it cost 17 guineas.
This radio was given to me by Jane Perrin who in turn was given it as a twenty first birthday from her parents in 1953. She put it out for the dustmen, reluctantly, back in June 2012 but her husband said "bring it in and think again", knowing she felt upset about chucking it out. Unbelievably, as its quite heavy, she touted that radio round, all through her nursing career and then from bed-sit to bed-sit round London whilst at Art school. It had very good sound quality and she enjoyed Radio Luxembourg in those days and rather despised the little portable radios that looked like suitcases that her nursing friends and I called 'Tart boxes' - how snobby ! Unfortunately, since she got, smaller, more up to date radios (though this followed her through the first years of her marriage - getting new valves from a shop in Shepherds Bush) the poor old thing was put in the garden shed where the sun did its worst on the veneer.
This is how it looked when it came to me.
The crazed lacquer on the veneered case was removed with a scraper and varnish remover, it was then sanded with grade 400 wet and dry paper. I then stained the central portion surrounded by the inlay with a walnut stain and left it to dry overnight before treating the whole casing with two applications of Danish oil. The expanded metal speaker grille was washed, dried and re-sprayed with gold paint.
The inside was full of dust.
After a preliminary clean to get rid of most of the dust. I quickly established that the valve heaters were all OK and glowed when the set was switched on though the dial lamp was open circuit and the current drawn was somewhat higher than the service sheet suggested. It was established that the output stage was OK as putting a finger on the pick up terminal elicited a healthy hum. As there was no signal on any waveband it was clear that I would need to get to work on the underside of the chassis.
Rear view of chassis after brushing away most of the dust.
Underside of chassis before repair.
I clamped the inverted chassis between two pieces of wood so that it could stand on the workbench and set to work checking voltages and resistance values. In the end the dial lamp,three wax coated capacitors, two 1/2 watt resistors and the main HT smoothing resistor were changed. I also replaced the mains lead with a 3 core one and earthed the chassis.
A 470kHz signal from my signal generator now came through loud and clear, which meant that the fault lay in the frequency changer circuit, the voltages on the anodes and screen were much less than they should have been, though I could not find anything wrong with the components. I changed the X79 valve but still silence. I had three old valves and each failed to elicit sound. When I tested these three and the one in the set on my valve tester they all were apparently dead. This seemed odd, I wondered if the tester had failed, but no, it worked fine with valves of a different type. As there was little to lose I decided to try a short period of defibrillation by upping the heater voltage for a few seconds and would you believe two of the four awoke from the dead. The best of the two is now inside and the radio now works on the long and medium wavebands but not the shortwave. I imagine that this is because the emission of the X79 oscillator is still rather low, but I am reluctant to press my luck by subjecting it to a further application of over voltage.
All back together and working.
More recently [May 2017] John Lyons came across my site when
searching for old radios or models he owned: WW2 civilian
receiver and the GEC BC5442. both in working order. The BC5442 was
purchased for an aunt of his in 1953, he remembers going to the radio
shop with his Dad to buy it for her. He still has the original receipt,
it cost £19-13-7d, quite a lot of money in those days. His old aunt
never had a TV and this radio was always on. He recalls that it had a
lovely tone and says "its a bit crackly nowadays, rather like
me!" He kindly scanned the instruction and installation guide dated
6/51 which is reproduced here.