Very rare pair of Osram DA30 triode valves. These have been tested as very good; 60ma (100%)53ma (90%) Will ship worldwide.

Osram British MadeVintage Rare Matched Pair of DA30 Balloon Shape Valves TubesBlack Plates, Circular Foil & Mesh GettersFully Tested Strong & Matched on AVO VCM 163100% Book Spec = Ia 60 - Gm 3.5These Valves Test1) Ia 69 - Gm 4.62) Ia 75 - Gm 4.4Used, Supplied in White Boxes

Very rare pair of Osram DA30 triode valves. These have been tested as very good; 60ma (100%)53ma (90%) Will ship worldwide.

Very rare pair of Osram DA30 triode valves. These have been tested as very good; 60ma (100%)53ma (90%) Will ship worldwide.

1 Marconi DA30 triode tube Made in the U.K. and of vintage production. Excellent, NOS-testing tube. Strong Gm and Ip; meets new-spec. Free from gas or shorts. Listened in circuit- quiet with no noise or microphonics. Clean glass & pins. Hanging filaments. Bottom, cup-getters. Tight base w/ no cracks. Excellent gettering. No large chunks inside. Tested at real operating voltages on an Amplitrex AT1000 at two operating points. Tube operated 10 min ea. before tests to ensure stability. AT1000 test results: At 300v anode, -75v bias- Gm- 4250 µmohs, Ip= 81.6 mA. Spec from Marconi- 45 mA. At 500v anode, -150v bias- Gm- 3190 µmohs, Ip= 59.0 mA. Spec from Marconi- 30 mA. In conclusion- This tests as an excellent, NOS tube. An excellent addition to anyones collection. Money back guarantee you will not be disappointed. All items are 100% guaranteed to arrive as represented for 30 days upon arrival. We offer a full refund if you are not satisfied. Weve been selling vintage electronics since 1999 with perfect ebay feedback and many happy, satisfied customers. All items professionally packed to arrive safely with no extra handling costs. Our mission is to offer quality-tested tubes to make you happy with your purchase. Terms & Conditions: Payment must be received within 3 days of sale date. Items described to the best of my ability. Shipped by U.S. Priority Mail. If you have questions, please contact me BEFORE purchasing. Thank you!

Still thinning out my valve collection and offering a rare OSRAM DA30 triode tube. PLEASE NOTE - this tube is very low emission and not suitable for use - it is being sold as a display item ONLY. Lovely rich clear decals and the classic early 1930s balloon shape. Please see my 100% positive feedback and bid with confidence. Tube will be well packaged for shipping. Happy to post worldwide via the Ebay Global Shipping Programme or direct international mail. Thanks for looking.

This auction is for a rare DA30 tube branded Osram in excellent shape!Good looking tube.This DA30 is in working order and all four filaments glow OK please check pictures.It has been tested at 90mA with mA/V of 4 grid -90 grid. Happy biddingI ship worldwide.UK GBP 8; Europe GBP 16; Asia: Hong Kong Taiwan China South Korea Japan GBP 20 USA GBP 20