CRACKLING AMPLIFIER (21 may 2007)
Now that CDs, CVDs and even MP3s have become the standard in recorded music, quite a few gramophone owners must have wondered if it isn't about time to get rid of their old recordplayer.
But, unless it really stands in the way, it may be a more sensible thing to hold on to your amplifier. After all, one day you may come across a record that you want to play. And you realize it won't fit into your CD player, don't you?
Alright, but one day, you'll find that one great record. And, of course, you'll want to play it right away. You get your old gramophone out from its hiding place. And since modern audio devices are usually not very good at amplifying gramophone sounds, you'll get your old amplifier out as well. But soon it becomes clear that your amplifier is no good anymore: it produces horrible crackling noises. The volume knob is as good as unusable.
That's what happened to me recently. And I had almost passed my amplifier to the garbage man ... but it fitted so snugly into the niche I'd sawn out into a cupboard that I couldn't bring myself to throw it away.
Suddenly I remembered my former colleague Roy S, who I knew to be a real electronics wizard.
His advice was to use contact cleaner, an aerosol which should be sprayed into the volume adjustment device.
Opening up the amplifier was not very hard, and soon the culprit was found in the form of a variable resistor.
variable resistor (red arrow)
It took some searching before I found an opening in the resistor, but after the cleaner had been sprayed in, I waited an hour or so to allow it to do its work.
And when I had screwed down the lid to close the amplifier and connected the wires, it turned out to produce its former great sound again -- as if it came fresh from the shop!
So now you know this too: don't throw away your old amplifier ...
