Description

E80CF SIEMENS BY TELEFUNKEN TUBE GOLD PINS /TESTED WITH ROETEST V10 NOS /NEW QTY-1 Tested With Roetest V10 NOS/NIB 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. 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, 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. Please allow for the following shipping times: EU countries: 5-8 business days, on rare occasions a few days more USA: 10-15 business days, on rare occasions more South East Asia (Japan, Singapore, S. Korea, Hong Kong, Taiwan etc) 10 business days, on rare occasions more India, China, Russia, Kazakhstan, Pakistan, Indonesia, Malaysia, Thailand, Australia, South Africa etc: at least 15 business days, but frequently around 25 business days Please note that shipping cost is calculated at average. If you have any objections please contact me for a specific quotation.