Fuse Blown And Power On LED Found Short In NORGE 2060 Amplifier
This Amp was brought to me by a regular customer, with the complaint that one channel of the Amp was not working and later it became dead, i.e. even the Power On Led was not lighting up.
I opened the set and subjected it to thorough cleaning as usual. I found on inspection that the fuses of the left channel were blown. Naturally, whenever we find a fuse blown, we would not replace it without investigating the reasons for its failure, lest replacement of fuse alone should cause more damages.
I combed the entire left channel to locate any defective active or passive components and did not find any. The Capacitors were also in superb conditions and did not give me the thrill to replace them. So, I turned my attention the power on LED and found it to be dead short! This, in fact, was not common, unless there was a power surge or failure of the driver circuit. So, I combed the area thoroughly and did not find anything wrong and replaced the LED.
I saw that the male plug of the mains cord was in very bad shape and so cut it off to replace it with a three pin top, observing the Phase, Neutral and Earth points. As per Indian standards, the phase should be on the right, neutral should be on the left and earth should be on top. This is usually marked on the plug. Unlike in the foreign countries the earth pin is not female but a male pin, which goes into the socket like the other two on the wall plug.
After ensuring that everything was ok, and lubricating the controls and connectors, I powered the set on and found it to be working very well. I allowed it to run for a few hours, before fixing the top cover and passing it to the delivery section. Mission accomplished without any compromise to add satisfaction to the collection bag!
This article was prepared for you by Parasuraman Subramanian from India. He is 72 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.
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Albert van Bemmelen
January 9, 2023 at 10:48 pm
This was a rather unexpected quick repair with both still good amplifier endstages. Only caused by a defect power led, open fuse, and bad power cable. A lesser experienced engineer probably never would have noticed this to be an easy repair.
Tim Bianco
January 10, 2023 at 7:45 am
Good work sir!
Parasuraman S
January 10, 2023 at 4:30 pm
Many thanks!
Parasuraman S
January 10, 2023 at 4:29 pm
Many thanks for your encouraging comments!
Waleed Rishmawi
January 10, 2023 at 3:44 pm
I hope you were not disappointed because you did not replace any capacitors..LOL. any way, good repair my friend. have a blessed day.
Parasuraman S
January 10, 2023 at 4:31 pm
Ha! Ha! Yes, it would have made me happier if I had that chance too! (LOL) Many thanks for your comments!
Yogesh Panchal
January 10, 2023 at 6:48 pm
Good job! Sir,
Here Years of experience is worked otherwise anyone would take long time to diagnose the culprit.because Shorted LED is very rare case.
Parasuraman S
January 10, 2023 at 9:50 pm
Many thanks for your comments and encouragement!
RAJ
January 10, 2023 at 9:17 pm
Great Sir, thanks
Keith Wicks
January 11, 2023 at 4:31 am
You state:
"Unlike in the foreign countries the earth pin is not female but a male pin, which goes into the socket like the other two on the wall plug."
However, here in the UK, earth pins on mains plugs are always male. This applies to the current "square" pin plugs and also to the earlier round pin plugs.
Keith