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Musictube broken7/21/2023 But no, those cheap testers are bought preferably. The really good ones cost only twice as much, and the price difference is the same as a quad of new tubes. I do not think this situation changed recently, and when I see how people pay easily 350 Euro on Ebay for silly, useless testers, I can say yes, nothing changed ever since. Not knowing good tube testers can be build from almost nothing. The manufacturers, offering the more complex testers, and the buyers of those, must all have been pretty stupid, 70 years ago. Some others, when looking inside, surprise you with the transformer being so small you can hardly see it, and almost complete lack of electronic parts. It is just this which is Russian roulette with an unserviced tester.Īlso, think about this carefully: Some testers are large and heavy, and full of large transformers and electronics. But would you have needed a tube tester for this? If you already knew the good tube was good, and the bad tube was bad, the tester is supposed to tell you "how much". What can people do? They plug a new tube in it, and it tests good. You can measure the mains voltage, batteries and of course known resistors, and you get a fair indication about it's condition. Verify the functioning of an old multi meter is easy. So with a 110V tester, plugged into 115V mains, "just ok" tubes will test "very good". On top of that, anode voltage for testing, goes up 5% which has a very good effect on most tubes. Even when the difference is only 5%, a tube with a weak cathode, reacts very good to 5% more heater voltage. So do not fool yourself, and set those old testers to 240V if they have the option. If you noticed perhaps the same tube is not testing the same always, that is because of randomly changing mains voltage today. Very famous for this is, old 220V testers, today plugged into 238V, coming from 230V outlets. Or, vice versa, it tells you the tubes are "new" and they are intensively used. Perhaps it was used for many years like that, and the owner felt good about throwing those "too weak" tubes away, while they had only a very small sign of use. It is amazing how these can fool the user with a false impression of accuracy, each in their own way. More later, I learned that many unserviced vintage tube testers indicate complete false results, and nobody realizes that. Later I learned, the old tester was indicating too low value for all tubes, and perhaps these tubes were all fine. Not very accurate, but I only wanted to know of the tubes were good or bad. I thought an old tube tester is like an old multi meter. I didn't have much knowledge about tube testers. Same as me! I remember very well how I threw away a shoe box full of used ECC81, many Mullard and Philips, using a defective tester (in 1988) and they tested all in the '?' range. When you are here, you are probably are interested in tube testers in some way.
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