Description

E88CC =6922 PHILIPS MINIWATT SQ GOLD PIN TUBE TESTED WITH ROETEST V10 USED LOT OF 1 Pcs. Buyer will receive the exact tube seen in photos . The tubes were tested in a professional laboratory with one of the best performing Tube Testers available at the moment: ROETEST V10, and the results of the parameters can be seen in the attached PDFs Tested with Roetest V10, "the Rolls Royce of tube testers" [emissionlab quote], a wonderful german professional system for testing tubes, it shows everything about a tube. If you have experience in the field of tubes you can find in the photos and in the details below the testing / sorting procedure and all the results, and if you do not have the necessary experience to understand what is explained you can trust that we deliver only very good tubes. This is the best way to select pairs, based on overlapping curves. The tubes meet datasheet specifications, first the quality tests – filament test, shorts test, gassy test (Ig1, vacuum factor, Ia variation with 1M2 grid series resistor), kathode isolation (leakage to filament), then quantity tests – value of current for plate, G2, kathod, G1, value for transconductance, gain, G1 curve, Ia curve etc., all results for these tests can be seen on te datasheet delivered for each tube. Those who use tubes are more familiar with terms like bias, gain (µ), plate current, slope/transconductance, and maybe someone is wondering what the term „D of plate” in the measured data means. Its value in itself is not so important but it is useful to calculate the other parameters taking into account Barkhausen's tubular formula S x D x Ri = 1 (slope * penetration * internal resistance=1), where D is –dUg/dUa at Ia=const. Barkhausen vas a german physicist, he was “the guru” of tubes, his theory and formulas guided the entire period of electronic tubes.