This "Recent Repair" was kindly contributed by Christopher Capener.
This is a LW/MW/VHF table radio made in 1960. It has 5 valves and a metal rectifier. It also has gramophone input, tape recorder output and a moveable ferrite rod aerial for LW/MW. Piano keys used for band changing and for switching off the set.
I bought this radio at one of the Radiophile auctions for £2. I liked the large brass front behind the knobs that I had not seen before on a radio.
The radio was in a tatty condition when I bought it, all of
the brass was heavily tarnished and the wooden cabinet was scratched and had
lots of small burn marks on the top. There were also some dents in the brass
plating around one knob. The back panel was undamaged as well.
I removed the back panel and vacuumed most of the dust out with a 1" paintbrush and all looked in original untouched condition.
The chassis is only held in with 2 nuts and bolts at the rear of the chassis. There are 2 wooden blocks at the front of the chassis that are screwed down into the cabinet and sandwich a flange mounted on the front of the chassis. This holds the front of the chassis down. It is an odd arrangement to hold the chassis but it does it very well.
The loudspeaker leads have sockets on them which helps to remove the chassis completely without having to desolder leads. The volume and tone control knobs are the push on type and the tuning and aerial knobs are held on with grub screws. The chassis easily slides out when all of the piano keys are depressed at the same time.
The loudspeaker, speaker board and speaker cloth were removed as a complete assembly by removing 5 screws. The dial glass and brass knob surround was also removed at this time.
Cabinet and brass restoration
The brass knob surround was tackled first as it was very tarnished and had dents in. The dents were removed by placing 2 flat metal blocks either side of the dents and then carefully pressing them together in a vice. This removed much of the dents but one still showed up slightly. I decided to leave it at that for removing the dent as I could easily make it look a lot worse!
The brass surround was polished slowly and began to shine. It took many hours and a lot of Brasso to complete it. There are 5 brass channel sections that run around the front of the cabinet and speaker surround and some of these came loose when the radio was dismantled. All bar one came off easily. These were all polished as well and replaced later.
The wooden cabinet was scratched but not too badly. There were a lot of small burn marks on the top surface of the radio and it looked as if a smoker had put an ashtray on the top of it. I hoped the burns were not too deep. I carefully stripped the original finish as it was crazed in places. This removed much of the scratches but the burn marks still remained. I carefully sanded down the cabinet with a medium and then a fine grade of sandpaper. This removed all of the burn marks and the rest of the scratches. I covered over a slight flaw in the veneer with dark scratch remover. I then used Danish oil to finish the cabinet.
After being allowed to dry the brass channel sections were glued back into the cabinet and the brass knob surround was refitted along with the dial glass and speaker assembly.
The chassis in this radio is a bit odd as part of the chassis
is a conventional inverted "U" shape chassis with hand wiring and
part of the chassis (i.f transformers and detector stages) is a PCB. The mains
transformer is mounted on the end of the chassis.
There is an extra valveholder hole next to the EL84 output valve possibly for a push-pull version of this radio.
The chassis were in a very good order with no wax capacitors or signs of previous work and just needed a dust down. The piano switches were cleaned and lubricated carefully to stop them sticking down as was the ferrite rod rotator components.
The ferrite rod rotator is driven by dial cord that had become loose over time causing quite a bit of play in its movement. A new tension spring restored its operation. The ferrite rod rotator knob is concentric with the tuning knob and only takes around a third of a turn to rotate it to its limit of travel therefore it probably gets quite a bashing when the tuning knob is missed as there are no rubber cushions at the limits of travel.
After the usual checks the set was slowly brought up with a variac. One dial bulb was blown so I replaced it with an 8-volt type that gave a similar light output . There are 4 dial lamps 6.5 volt rated.
As the variac was wound up crackles could be heard in the speaker and switching to LW then tuning to 1500 meters radio 4 could be heard. I increased the variac a bit more and then changed to VHF and found radio 3 and classic FM (just!)
With the variac at full and a wire in the VHF aerial socket the radio sounded very good and clear with good volume. The EM80 tuning indicator was blank but after trial and error I found one in a cupboard which gave out a good light and was fitted. The volume and tone pots crackled a bit so I cleaned them with contact cleaner as well as the valveholders and the volume control is now smooth.
A new mains cable was fitted and the radio went back together without any problems. The chassis sits on rubber grommets that were still soft and were reused. The position of valves sheet was coming away from the side of the cabinet and was restuck down. There are 2 little feet at the front of the radio and these were cleaned up and refitted. The back panel was cleaned with a damp cloth and refitted. A 2 wire aerial for VHF is fitted on the back and gave good results so I left it connected.
The radio certainly stands out with the brass knob surround on the front and purple dial glass. The dial glass is neat and not too cluttered but they could have made the tuning indicator window look a bit better rather than just a square hole. The ferrite rod rotator doesn't work very well and the movement is very course, A poor bit of design here.
The radio has a nice large speaker that gives it a good sound. Tuning is easy and the radio is quite sensitive. Although the dial goes up to 100MHz you can tune past it to get Classic FM which is useful. The tuning indicator is not switched off when switched to the gram setting which seems a bit silly, as it isn't doing anything.
It certainly is a good radio to look out for. I was surprised that I won it at the Radiophile auction for £2 the only bidder.
I am very pleased with the restoration as the set looks very
good now than when I first bought it.
Text and Photos Copyright © 2005 Christopher Capener