1908 DEFOREST SINGLE WING SPHERICAL AUDION – DUAL FILAMENT
Item History & Price
| Reference Number: Avaluer:64554025 | Brand: DEFOREST |
| Model: SPERICAL AUDION | Type: Vacuum Tube |
DEFOREST SINGLE WING SPHERICAL AUDION – DUAL FILAMENTThis is the version of the spherical Audion in which there is 1 plate and 1 grid. This places this example into the 1908 time period. In 1909 they began making these tubes with 2 plates and 2 grids.There are however, 2 filaments. The filaments in these tubes were so delicate that in order to extend the life of the tube, 2 filaments were provided. When the first filament gave out, the operator could shift the filament connection to ...a separate wire that protruded from the screw base. Both filaments are burnt out.The photos constitute part of the description. Look carefully. PayPal is welcomed when shipped to verified addresses. Those of you who use PayPal already know that you can pay through them by credit card. Please bid only if you are serious and intend to honor your bid.EBay calculates the shipping costs that you see in this listing. I enter the shipping weight and they come up with the cost to ship, based on my location and the destination.For questions, contact me using "ask seller a question". Please ask your questions before bidding. We reserve the right to refuse to sell to bidders with negative or low feedback. I will not end the auction early - everyone gets a chance. We always leave appreciative Positive Feedback for all responsible auction winners! I pack and ship with care. During the 80's and early 90's, I sold antique radios by mail and shipped thousands of them and they all made it safely. (This was before eBay). Check my feedback rating. Transit times are subject to the carrier and eBay provides you with the tracking number. NO SALESTAX in my state.
