Servicing Two Valve Radios
I received two Valve Radios from a customer, with the complaint ‘No sound’. One was GEC and another UMS. Very sorry that I do not have the latest picture of UMS, as I forgot to click it. What I have put here is an old snap taken a few years back in my very old mobile. (Both of these Radios had come to me for service a few years back in a totally bad condition, having bought from a scrap dealer.
I had to do a lot of work to bring these two to working condition then!)
I opened UMS and found a burnt resistor on the output transformer and found the primary of the transformer was open. In order to ensure that all else was ok, I connected an output transformer, which I always keep in stock for testing purposes. The Radio worked very well. Since the transformer has to go for rewinding, I kept this set aside and opened the GEC. Surprisingly and coincidently, that was the same problem in that set too! Removed it. Checked GEC also similarly using the testing output transformer and found the Radio to be working very well, the output of EZ80 Rectifier valve was not that good.
Got back the transformers rewound after a week and refit them. Both Radios performed very well. Unfortunately, I forgot to click further snaps of these two lovely Radios. GEC service was already covered by me in yet another article published long back.
Jobs completed, but not to my full satisfaction, as this customer did not want to spend money on complete refurbishing.
This article was prepared for you by Parasuraman Subramanian from India. He is 68 years old and has more than 30 years’ experience in handling antique equipment like Valve Radio, Amps, Reel Tape Recorders and currently studying latest tech-classes conducted by Kerala State Electronics Technicians’ Association. He has done graduation in BBA degree, private diploma in Radio Engineering and retired as MD of a USA company. Presently working as Consultant to Hospital and other institutions.
Please give a support by clicking on the social buttons below. Your feedback on the post is welcome. Please leave it in the comments.
P.S-If you enjoyed reading this, click here to subscribe to my blog (free subscription). That way, you’ll never miss a post. You can also forward this website link to your friends and colleagues-thanks!
You may check on his previous repair article below: