Used Vacuum Tube General Electric 4D21 4-125 Germany

Description: You are looking at a used General Electric 4D21 4-125A vacuum tube made in Germany. Serial no. D9288. Base has some scratches on it. Tube is in excellent shape and looks great. We are not able to test this tube, but we have tested the filament, and it tests as "good." The tube does not have its original box, so we will pack it extra carefully for shipment. If this tube is not what you are looking for, please look at the other tubes we have in our store. How we test our tubes: Before we stock, sell or ship, each tube is fully tested on our calibrated Hickok 539C tube tester. Every tube, whether used, NOS (New Old Stock), or NIB (New In Box) is tested for shorts using our Hickok 539C Ohm-meter. We don’t neon test for shorts, as it isn't a sensitive enough test. We test the tubes for shorts hot and cold to 50MOhms. All tubes are gas leak tested to ensure the reliable performance of the tube. We test all tubes for mutual conductance (sometimes referred to as trans-conductance) including each section, if applicable. Hickok 539C provides a minimum acceptable mutual conductance. We will not sell tubes that meet these minimums. Most tube manufacturers provide new tube mutual conductance range(s), and we test to these range(s). If a used or NOS tube is on the lower end of the manufacturer's range we discount the price of the tube. We try to post manufacturers' mutual conductance range(s), and the Hickok minimum values for each tube we sell, so you can make an informed decision on your purchase. We also life test every tube. This is a test where the filament voltage is reduced by 10%, which gives an indication of the future performance of the tube. We discard any used or NOS tube that does not meet the life test. If any test results in failure for shorts, leaks or open filaments, we discard the tube, and will never list it. Tube and box condition: If we have doubts about the NOS status of a tube, we sell it as used, even if the tube has a good box. Remember, all of our tubes whether used, NOS or NIB are fully tested before we sell them. We sometimes have tubes with loose bases. Our policy is to note this on the tube's description, and discount the price of the tube accordingly. We don’t sell any tube with a significantly loose base, unless the tube is exceptionally rare. If this is the case, it will be well noted in the tube's description. You can be sure that when we say a base is loose, it is only slightly loose and can be used as-is. Some of our tubes come with original boxes. If the used, NOS or NIB tube description does not indicate the tube is packed in its original box, it will be packed in a new, standard white box. If a used, NOS or NIB tube has an original box, we will also describe its condition, as often the box is just as interesting and collectable as the tube itself. If any used, NOS or NIB tube has an original box in poor condition and we pack it in a new standard white box, we will give you the original box as well. Since we open all boxes to test them, sometimes the box flaps or tabs are damaged and we will note this in the description of the tube. If a used, NOS or NIB tube is packed in a new standard white box, the box will have the tube's test results on its label. If the tube is packed it its original box, we provide separate test results on the packing list so we don't damage the tube's original box. Our simple warranty: We believe each tube should have an appropriate warranty, regardless if it is used, NOS or NIB, we do not sell as-is. If you are not delighted with your purchase, let us know and we will authorize the return of the tube. We may be able to provide another tube from our large inventory - your choice.To improve our quality, we would like to understand the reason for the return, but it is not a requirement. Returns must include the original box in the same condition (if applicable), and be packed in the original packaging. Purchaser must pay return shipping fees. When we receive the return, we will refund your purchase price (excluding original shipping fees) within 72 hours. We want you to be happy with your purchase, and will work with you if you have any concerns or problems. Please contact us to work out a mutually beneficial solution before writing negative feedback. About us: We have a collective 30+ years of experience in electronics and vacuum tubes. We have professional credentials and qualification in electronics and testing. Our staff has designed a significant number of vacuum tube-based equipment. It is not only our business, but also our hobby to design and refurbish vacuum tube equipment. Our supply of tubes: We buy all of our tubes from reliable sources and are always on the look out for quality tubes and tube suppliers. Special thanks to Frank Philipse (whose web site is tubedata.org) and other host sites of vacuum tube data. These are wonderful sites full of PDF specifications of vacuum tubes. Powered by eBay Turbo Lister The free listing tool. List your items fast and easy and manage your active items.

Price: 48.99 USD

Location: Denver, Colorado

End Time: 2024-12-19T18:42:05.000Z

Shipping Cost: N/A USD