I have one of these radios myself, and it sits in my hallway, minding it's own business. It's VHF doesn't work, and the speaker cloth is ghastly. But a friend of mine passed comment on it... "I've got one of those! Can you get it going for me?" Of course I can ....
Arrival. A few issues are immediately obvious. The case is cracked, the dial glass is broken, there's no pointer in the dial...
Not much we can do about the crack, unless we fill it using car body filler, flat it and paint it up to look like bakelite.
Electronically, things are looking better...
Chassis is removed and examined.
The on/off volume control is a replacement, but has worked lose, and has wrenched all it's wiring off, and the suppressor cap has long since exploded!.....
... Here's it's other end!
Plenty of horrible hunts. These have little cardboard sleeves, wrapped round little black caps, which interestingly have the value printed directly on the cap's body too!
The more traditional wax cap. They will all have to go!...
... as well as re-stuffing the electrolytic's where possible.
The mains smoother has been replaced in the past, with this expensive component! .... we'll see how it reforms....
... And after a few hours on the "Dreadnaught" capacitor reformer, it passes with flying colours, exhibiting correct capacity and acceptable ESR & leakage.
Case is removed....
... and given a bath
Chassis and dial is cleaned. Tuning is re-strung...
... and a dial pointer fabricated...
... capacitors changed, and electrically tested, medium wave and long wave working well, but no VHF reception....
VHF tuner is removed (a tedious job)...
... and a small decoupling capacitor is found to be electrically leaky (no surprise, it's a Hunts!) ... and VHF operation is restored...
This radio also has a "gram" setting. This allowed connection of a record player (gramophone) back in the day. My friend wished to connect it to his iPod. The gram input was originally electrically isolated from the live mains chassis by some (now replaced) capacitors. Now in this day and age, I'm not happy with one side of the chassis being connected to neutral, and using this method to isolate a hand held device.
So I've fitted a small audio isolation transformer, which is eventually fitted to a bracket by the IF transformer. This is checked with a megger tester to confirm isolation from the mains.
Now all that remains is to re-assemble and sit back and listen!
Caroline ... on 319!!!
.... now I really should look at mine ....
... Here's it's other end!
VHF tuner is removed (a tedious job)...
Absolutely top restoration/upgrade! Have listened to it every day since it was saved and it sounds fantastic. Very pleased
ReplyDeleteAnother first class job by the Doswell entity, keep them coming Andy!
ReplyDeleteI have had one of these sets for years noticed losing volume a slight distortion after set has been on for a while any idea which cap. may be at fault
ReplyDeletemike@northernsoulnights.com
Check the cap feeding the grid of the UL84 for starters, but it's difficult to say without seeing it, and taking some measurements.
ReplyDeleteThanks for that will check today and get back with results, best supplier for replacement parts.
Deletemike
I've just inherited one of these radios. Really want to do it up but sadly don't have enough test kit. Only FM works. Its a joy to see a clean inside, the one I have is caked in dust and its really hard to removed from all the wires. One days I'll pluck up the courage to replace a few bits.
ReplyDelete